loss of torque with light flywheel?
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Re: loss of torque with light flywheel? (86crxintheworks)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 86crxintheworks »</TD></TR><TR><TD CLASS="quote">im about to order a clutch and flywheel for my build and i have ben reading up on what other people have experienced and i came across someone saying that ull loose torque with a light flywheel on a boosted setup...thoughts and opinions???? ill be running around 350 to 400 hp on a ls vtec turbo setup.fully built.will a lightweight flywheel make me loose torque???</TD></TR></TABLE>
A lightened flywheel will not make you lose torque. I can see how people can perceive that it does though. For example, in my S2000 I have to ride the clutch a little to get a decent launch...even on the street. If I give it too little gas or release the clutch too much, the engine gets dragged down to its ~0 lb-ft torque range and it takes a while to get out of there. I imagine that with a lighter flywheel, there would be less room for error as the engine would get dragged down to this ~0 lb-ft rang much easier...since it has less momentum.
This can be perceived as "loss of torque." It isn't though...it just means I suck at driving and can't keep the engine in its power band.
A heavy flywheel can "rob" power, but only under certain circumstances. A flywheel's job is to absorb energy...to resist acceleration. It does it primarily to smooth out the power pulses of the engine. A side effect is that it also robs power when it's being rotationally accelerated. This means that the faster the engine is spinning up, the more power it robs. This can show up on an inertial dyno: The more powerful the engine, the more acceleration, the more power it robs. Also, the lower the gear you're in, the more acceleration, the more power it robs. The biggest difference, however, is when the car is in neutral. This allows the highest rotational acceleration of the engine...and allows the flywheel to rob the most power. You can see this by how long it takes the engine to rev up or down.
If you're not accelerating, such as when doing a top speed run, or simply towing something....there should be 0 decrease in power/ torque. Same top speed, same towing capacity.
A lightened flywheel will not make you lose torque. I can see how people can perceive that it does though. For example, in my S2000 I have to ride the clutch a little to get a decent launch...even on the street. If I give it too little gas or release the clutch too much, the engine gets dragged down to its ~0 lb-ft torque range and it takes a while to get out of there. I imagine that with a lighter flywheel, there would be less room for error as the engine would get dragged down to this ~0 lb-ft rang much easier...since it has less momentum.
This can be perceived as "loss of torque." It isn't though...it just means I suck at driving and can't keep the engine in its power band.
A heavy flywheel can "rob" power, but only under certain circumstances. A flywheel's job is to absorb energy...to resist acceleration. It does it primarily to smooth out the power pulses of the engine. A side effect is that it also robs power when it's being rotationally accelerated. This means that the faster the engine is spinning up, the more power it robs. This can show up on an inertial dyno: The more powerful the engine, the more acceleration, the more power it robs. Also, the lower the gear you're in, the more acceleration, the more power it robs. The biggest difference, however, is when the car is in neutral. This allows the highest rotational acceleration of the engine...and allows the flywheel to rob the most power. You can see this by how long it takes the engine to rev up or down.
If you're not accelerating, such as when doing a top speed run, or simply towing something....there should be 0 decrease in power/ torque. Same top speed, same towing capacity.
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Re: loss of torque with light flywheel? (Lsos)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Lsos »</TD></TR><TR><TD CLASS="quote">
This can be perceived as "loss of torque." It isn't though...it just means I suck at driving and can't keep the engine in its power band.</TD></TR></TABLE>
HOLY CRAP! Someone on H-T that is actually willing to admit that they, the driver might be the cause of thier drivability issues, not the lightweight flywheel.
Sir, I salute you. You have reached an enlightened state most never even imagine exists.
To everyone else, as has been stated earlier (several times), learn to drive your car and stop blaming the flywheel.
This can be perceived as "loss of torque." It isn't though...it just means I suck at driving and can't keep the engine in its power band.</TD></TR></TABLE>
HOLY CRAP! Someone on H-T that is actually willing to admit that they, the driver might be the cause of thier drivability issues, not the lightweight flywheel.
Sir, I salute you. You have reached an enlightened state most never even imagine exists.
To everyone else, as has been stated earlier (several times), learn to drive your car and stop blaming the flywheel.
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Re: loss of torque with light flywheel? (FarinaMotorsports)
Well i am bringing thing back from the dead almost..because i said that i would have some kind of proof....i am not ******* on the OEM flywheel or the lighter flywheel..in fact i liked driving around on the lighter flywheel..revved so much faster!! anyway let me try and explain what my experence was..
My setup: DC2 321whp@10psi 57trim stock internal gsr
I recently changed my Flywheel from the fidanza 7.5lb back to the OEM GSR flywheel..
with the fidanza flywheel with roughly 20-30 passes at the track my best 1/4 mile time was :
60' 2.171
1/8 8.505@89.35
1/4 12.823@114.78
and my best trap speed was 116.00 with the fidanza flywheel. All of the runs were done on street tires. 205/50/15 Nitto Neogen tires..
now after i changed back to the OEM flywheel my car just didnt feel as fast. and i had doubts on if it was really faster or not...since i am a 1/4mile ***** i had to go back and test it out.
i have not upped the boost or anything else since my last runs. the weather and track conditions are almost identical..it was still about 40-43 degrees out..
my new best time up to date is:
60' 2.112
1/8 8.447@89.99
1/4 12.809@115.41
'now i know that isnt a drastic change but her is the kicker..my new highest trap speed is 117.44mph and 91.17 1/8mile trap....now like i said track conditions, weather and weight in the car was almost identical...still had my little tool box in the back of my car and a 1/2 tank of gas...
i said i would bring back some test results and well here are the only ones that i can give you...i dont know what else it could have been...everything was almost the same...and yet with more weight i ran a better time and faster trap speed?? can someone explain the physics there? not trying to be a dick but im lost here!!
just thought id let you guys know...
My setup: DC2 321whp@10psi 57trim stock internal gsr
I recently changed my Flywheel from the fidanza 7.5lb back to the OEM GSR flywheel..
with the fidanza flywheel with roughly 20-30 passes at the track my best 1/4 mile time was :
60' 2.171
1/8 8.505@89.35
1/4 12.823@114.78
and my best trap speed was 116.00 with the fidanza flywheel. All of the runs were done on street tires. 205/50/15 Nitto Neogen tires..
now after i changed back to the OEM flywheel my car just didnt feel as fast. and i had doubts on if it was really faster or not...since i am a 1/4mile ***** i had to go back and test it out.
i have not upped the boost or anything else since my last runs. the weather and track conditions are almost identical..it was still about 40-43 degrees out..
my new best time up to date is:
60' 2.112
1/8 8.447@89.99
1/4 12.809@115.41
'now i know that isnt a drastic change but her is the kicker..my new highest trap speed is 117.44mph and 91.17 1/8mile trap....now like i said track conditions, weather and weight in the car was almost identical...still had my little tool box in the back of my car and a 1/2 tank of gas...
i said i would bring back some test results and well here are the only ones that i can give you...i dont know what else it could have been...everything was almost the same...and yet with more weight i ran a better time and faster trap speed?? can someone explain the physics there? not trying to be a dick but im lost here!!
just thought id let you guys know...
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and my case is rested. i want to give a shout out to all the people who doubted what i had to say in this thread especially legion and all his physics bullshit. real world conditions can be a bitch cant they?
once again lightweight flywheels are good for any n/a engine. but with a big boosted engine you are better off with a oem flyweel. (unless you have a pro drag car running 8's or something with all the high tech crap they have such as $1500 shifters, etc.)
congrats on your new best.
Modified by mike93eh2 at 12:35 AM 4/22/2008
once again lightweight flywheels are good for any n/a engine. but with a big boosted engine you are better off with a oem flyweel. (unless you have a pro drag car running 8's or something with all the high tech crap they have such as $1500 shifters, etc.)
congrats on your new best.
Modified by mike93eh2 at 12:35 AM 4/22/2008
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Re: (EARLdaSQUIRREL)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EARLdaSQUIRREL »</TD></TR><TR><TD CLASS="quote">
take your car and run it at the track, then take your car put a lightweight flywheel on it and run it at the track again, i bet your trap speed and times are faster with the lightweight flywheel
</TD></TR></TABLE>
oh snap!
take your car and run it at the track, then take your car put a lightweight flywheel on it and run it at the track again, i bet your trap speed and times are faster with the lightweight flywheel
</TD></TR></TABLE>
oh snap!
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Re: (mike93eh2)
Thanks man!
I am not trying to bash on what anyone said...i am just giving you my test results on my car....from what i learned in high school just because something works on paper doesnt always mean it works in real life...youd think that a lighter flywheel would really make you faster and simple physics would tell you the same...but maybe momentum comes into play here? more momentum with the OE flywheel... and i thought that my car felt slower but in reality its faster...
Modified by gringotegra at 10:44 PM 4/21/2008
I am not trying to bash on what anyone said...i am just giving you my test results on my car....from what i learned in high school just because something works on paper doesnt always mean it works in real life...youd think that a lighter flywheel would really make you faster and simple physics would tell you the same...but maybe momentum comes into play here? more momentum with the OE flywheel... and i thought that my car felt slower but in reality its faster...
Modified by gringotegra at 10:44 PM 4/21/2008
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Re: (gringotegra)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mike93eh2 »</TD></TR><TR><TD CLASS="quote">and my case is rested. i want to give a shout out to all the people who doubted what i had to say in this thread especially legion and all his physics bullshit. real world conditions can be a bitch cant they?
once again lightweight flywheels are good for any n/a engine. but with a big boosted engine you are better off with a oem flyweel. </TD></TR></TABLE>
LMAO, you're such an idiot!! Look at the two sides here - the smart/educated people agree that lighter is better. The idiots (namely you) say OEM is better (based on absolutely nothing).
If you think physics is "bullshit," you might as well stop right there. Nobody is going to listen to someone who doesn't believe in physics. Witchcraft! Like I said, it's *physically impossible* for a car to be faster with a heavier flywheel.
once again lightweight flywheels are good for any n/a engine. but with a big boosted engine you are better off with a oem flyweel. </TD></TR></TABLE>
LMAO, you're such an idiot!! Look at the two sides here - the smart/educated people agree that lighter is better. The idiots (namely you) say OEM is better (based on absolutely nothing).
If you think physics is "bullshit," you might as well stop right there. Nobody is going to listen to someone who doesn't believe in physics. Witchcraft! Like I said, it's *physically impossible* for a car to be faster with a heavier flywheel.
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Re: (Legion)
but how can anyone believe anything an illiterate dumbass such as yourself has to say ?? why are you even here ? dont you have to get banned again ? or maybe talk about your 350whp car ? lol
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Re: (zex_cool)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by zex_cool »</TD></TR><TR><TD CLASS="quote">but how can anyone believe anything an illiterate dumbass such as yourself has to say ?? why are you even here ? dont you have to get banned again ? or maybe talk about your 350whp car ? lol </TD></TR></TABLE>
Illiterate... that's rich. I'm here for the sole purpose of shutting down idiots like you and stopping the spread of misinformation.
Illiterate... that's rich. I'm here for the sole purpose of shutting down idiots like you and stopping the spread of misinformation.
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Re: (Legion)
it may be physically impossible on paper..but in real life it happened...**** doesnt always work out the same on paper as it does in real life...i proved what i could with what i had... does anybody else have any cold hard evidence?
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Re: (gringotegra)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by gringotegra »</TD></TR><TR><TD CLASS="quote">it may be physically impossible on paper..but in real life it happened...**** doesnt always work out the same on paper as it does in real life...i proved what i could with what i had... does anybody else have any cold hard evidence?</TD></TR></TABLE>
I'm not knocking you, I'm just saying there are other variables involved. There are no benefits to having a heavier flywheel. Even the OEM proponents have not listed any benefits, they're just speculating that it's better. Conversely, there are some very real, very known disadvantages to having a heavier flywheel.
And people who argue that physics is worthless because it doesn't apply to "real world" applications are always merely defending the fact that they don't understand it. 99% of the tangible products in this world (including cars/engines) are produced based on math/science/physics. They aren't just whipped up experimentally because "physics doesn't apply to the real world." The "real world" argument is such a cop-out.
I'm not knocking you, I'm just saying there are other variables involved. There are no benefits to having a heavier flywheel. Even the OEM proponents have not listed any benefits, they're just speculating that it's better. Conversely, there are some very real, very known disadvantages to having a heavier flywheel.
And people who argue that physics is worthless because it doesn't apply to "real world" applications are always merely defending the fact that they don't understand it. 99% of the tangible products in this world (including cars/engines) are produced based on math/science/physics. They aren't just whipped up experimentally because "physics doesn't apply to the real world." The "real world" argument is such a cop-out.
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Re: (Legion)
I totally agree with you..and i know that everything out there was created somehow by math,science or physics...and i know that 8lbs of rotating mass = 100lbs of dead weight..right? so how in the hell did i manage to trap almost 2mph more with the extra "dead" weight in my motor/transmission?? i mean i also know that 100lbs in the 1/4= 1/10th of a second...so just by saying that youd think i would have been faster before...so why now with the heavier flywheel was i able to trap higher? im not a physics expert...nor am i any good at explaining...but i do like to dragrace and i had over 300runs last year...and im no expert at it but i do prety well...
it would be different if i had a faster time and a lower trap speed..or if i had a faster trap with a slower time...but i did both here...higher trap and a faster time...is there anyway you can explain the physics here Legion? or anybody for that fact...thanks
it would be different if i had a faster time and a lower trap speed..or if i had a faster trap with a slower time...but i did both here...higher trap and a faster time...is there anyway you can explain the physics here Legion? or anybody for that fact...thanks
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Re: (gringotegra)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by gringotegra »</TD></TR><TR><TD CLASS="quote">i know that 8lbs of rotating mass = 100lbs of dead weight..right?</TD></TR></TABLE>
Flywheels are a bit funny, and there's no set formula for determining the gains. The inertial losses consumed by a flywheel is dependent on engine acceleration, whereas the acceleration of the car itself is dependent on the transmission/FD acceleration. The end result is that a lightened flywheel mimics a high weight loss in 1st gear, and the gains taper down to almost nothing by 5th gear.
So basically, the greatest gains with a lightweight flywheel are seen in 1st/2nd gear, and this usually translates to better 60' times (disregarding traction issues). So what can I say... I have absolutely no idea how you cut a better 60' with the heavier flywheel.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">is there anyway you can explain the physics here Legion? or anybody for that fact...thanks</TD></TR></TABLE>
Absolutely not
Flywheels are a bit funny, and there's no set formula for determining the gains. The inertial losses consumed by a flywheel is dependent on engine acceleration, whereas the acceleration of the car itself is dependent on the transmission/FD acceleration. The end result is that a lightened flywheel mimics a high weight loss in 1st gear, and the gains taper down to almost nothing by 5th gear.
So basically, the greatest gains with a lightweight flywheel are seen in 1st/2nd gear, and this usually translates to better 60' times (disregarding traction issues). So what can I say... I have absolutely no idea how you cut a better 60' with the heavier flywheel.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">is there anyway you can explain the physics here Legion? or anybody for that fact...thanks</TD></TR></TABLE>
Absolutely not
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Re: (Legion)
Funny thread.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by gringotegra »</TD></TR><TR><TD CLASS="quote">Ihigher trap and a faster time...is there anyway you can explain the physics here Legion? or anybody for that fact...thanks</TD></TR></TABLE>
I just want to point out that few people mentioned a flywheel affect acceleration AND deceleration. Remember that you do both when driving down the track. I don't know actual percentage but out of the total 1/4 time, part is spent on acceleration, the other part is shifting (clutch engaged). Since lighter FW means faster tq loss during each shift, it appears this affects your total 1/4 time more so then the benefit of faster acceleration inbetween shifts.
Another variable not yet discussed in this thread is when car is accelerating, FW is accelerating under load. Soon as clutch is engaged the FW is decelerating with comparably NO load.
For those that don't know, the only reason "real world" many times does not match "on paper" is because there are variables missing (over looked or not considered) in the equations on paper. Physics is never bs, only the person doing the math is. You will always be able to correlate the two.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by gringotegra »</TD></TR><TR><TD CLASS="quote">Ihigher trap and a faster time...is there anyway you can explain the physics here Legion? or anybody for that fact...thanks</TD></TR></TABLE>
I just want to point out that few people mentioned a flywheel affect acceleration AND deceleration. Remember that you do both when driving down the track. I don't know actual percentage but out of the total 1/4 time, part is spent on acceleration, the other part is shifting (clutch engaged). Since lighter FW means faster tq loss during each shift, it appears this affects your total 1/4 time more so then the benefit of faster acceleration inbetween shifts.
Another variable not yet discussed in this thread is when car is accelerating, FW is accelerating under load. Soon as clutch is engaged the FW is decelerating with comparably NO load.
For those that don't know, the only reason "real world" many times does not match "on paper" is because there are variables missing (over looked or not considered) in the equations on paper. Physics is never bs, only the person doing the math is. You will always be able to correlate the two.
Re: (mike93eh2)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mike93eh2 »</TD></TR><TR><TD CLASS="quote">and my case is rested. i want to give a shout out to all the people who doubted what i had to say in this thread especially legion and all his physics bullshit. real world conditions can be a bitch cant they?
once again lightweight flywheels are good for any n/a engine. but with a big boosted engine you are better off with a oem flyweel. (unless you have a pro drag car running 8's or something with all the high tech crap they have such as $1500 shifters, etc.)
congrats on your new best.
Modified by mike93eh2 at 12:35 AM 4/22/2008</TD></TR></TABLE>
Just curious as to WHY it's now okay to use a lightweight flywheel if you have a pro drag car with "high tech crap." I guess ignorance is bliss :shruggs:
You argued 4 pages of pure bullshit, and seem to have come to the conclusion that it's okay as long as you have a pro drag car.
So let me get this straight:
Lightened flywheels are SUPER BAD on a turbo honda with a big motor.
They are horrible and make your car so much harder to drive and do not help.
BUT it's okay as long as your trying to be the fastest out there and competing amongst others of the same class, which would easily be big motors and turbo to run 8's. If you reach that class of super fast hondas with big power, then you can embrace the lightened flywheel as if it where one of your own
once again lightweight flywheels are good for any n/a engine. but with a big boosted engine you are better off with a oem flyweel. (unless you have a pro drag car running 8's or something with all the high tech crap they have such as $1500 shifters, etc.)
congrats on your new best.
Modified by mike93eh2 at 12:35 AM 4/22/2008</TD></TR></TABLE>
Just curious as to WHY it's now okay to use a lightweight flywheel if you have a pro drag car with "high tech crap." I guess ignorance is bliss :shruggs:
You argued 4 pages of pure bullshit, and seem to have come to the conclusion that it's okay as long as you have a pro drag car.
So let me get this straight:
Lightened flywheels are SUPER BAD on a turbo honda with a big motor.
They are horrible and make your car so much harder to drive and do not help.
BUT it's okay as long as your trying to be the fastest out there and competing amongst others of the same class, which would easily be big motors and turbo to run 8's. If you reach that class of super fast hondas with big power, then you can embrace the lightened flywheel as if it where one of your own
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Re: (turbosi03)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turbosi03 »</TD></TR><TR><TD CLASS="quote">Funny thread.
I just want to point out that few people mentioned a flywheel affect acceleration AND deceleration. Remember that you do both when driving down the track. I don't know actual percentage but out of the total 1/4 time, part is spent on acceleration, the other part is shifting (clutch engaged). Since lighter FW means faster tq loss during each shift, it appears this affects your total 1/4 time more so then the benefit of faster acceleration inbetween shifts.
Another variable not yet discussed in this thread is when car is accelerating, FW is accelerating under load. Soon as clutch is engaged the FW is decelerating with comparably NO load.
For those that don't know, the only reason "real world" many times does not match "on paper" is because there are variables missing (over looked or not considered) in the equations on paper. Physics is never bs, only the person doing the math is. You will always be able to correlate the two. </TD></TR></TABLE>
thank you!! very well put indeed...i do understand that i needed to shift faster with the lighter and i did...i full throttle shifted 1->2 3->4....when shifting into every gear i never dropped below 6000rpm...i dont know the exact rpm in each gear.....i personally think this 7.5lb FW was probably too light for my setup...a 10-12lb FW would have probably been a better choice...im not ******* on the light FW i actually liked it alot...
I totally agree with you again on the physics side...it should always work out somehow..
I wish i could have gotten more Practice on the lighter FW and maybe i could have seen different results...all i can say is my car is faster with the OE flywheel...i have about 10 timeslips to prove it...i wish there was some calculation that we could use to determine the exact gain/loss you would actually get by changing your FW given all the other variables are exactly the same...
I just want to point out that few people mentioned a flywheel affect acceleration AND deceleration. Remember that you do both when driving down the track. I don't know actual percentage but out of the total 1/4 time, part is spent on acceleration, the other part is shifting (clutch engaged). Since lighter FW means faster tq loss during each shift, it appears this affects your total 1/4 time more so then the benefit of faster acceleration inbetween shifts.
Another variable not yet discussed in this thread is when car is accelerating, FW is accelerating under load. Soon as clutch is engaged the FW is decelerating with comparably NO load.
For those that don't know, the only reason "real world" many times does not match "on paper" is because there are variables missing (over looked or not considered) in the equations on paper. Physics is never bs, only the person doing the math is. You will always be able to correlate the two. </TD></TR></TABLE>
thank you!! very well put indeed...i do understand that i needed to shift faster with the lighter and i did...i full throttle shifted 1->2 3->4....when shifting into every gear i never dropped below 6000rpm...i dont know the exact rpm in each gear.....i personally think this 7.5lb FW was probably too light for my setup...a 10-12lb FW would have probably been a better choice...im not ******* on the light FW i actually liked it alot...
I totally agree with you again on the physics side...it should always work out somehow..
I wish i could have gotten more Practice on the lighter FW and maybe i could have seen different results...all i can say is my car is faster with the OE flywheel...i have about 10 timeslips to prove it...i wish there was some calculation that we could use to determine the exact gain/loss you would actually get by changing your FW given all the other variables are exactly the same...
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Re: (gringotegra)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turbosi03 »</TD></TR><TR><TD CLASS="quote">I just want to point out that few people mentioned a flywheel affect acceleration AND deceleration. </TD></TR></TABLE>
The deceleration part doesn't matter; that's compensated for by faster shifting. The RPMs still have to drop to the same level regardless of flywheel weight.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">Since lighter FW means faster tq loss during each shift</TD></TR></TABLE>
You aren't making torque during a shift. The throttle plate is closed and no fuel is being injected.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">it appears this affects your total 1/4 time more so then the benefit of faster acceleration inbetween shifts. </TD></TR></TABLE>
Not possible.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">Another variable not yet discussed in this thread is when car is accelerating, FW is accelerating under load. Soon as clutch is engaged the FW is decelerating with comparably NO load. </TD></TR></TABLE>
Can you elaborate? I'm not following you.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boostedDA »</TD></TR><TR><TD CLASS="quote">Just curious as to WHY it's now okay to use a lightweight flywheel if you have a pro drag car </TD></TR></TABLE>
It's a pretty well known fact that drag cars need HEAVIER flywheels. I covered that on page 1 I believe. If you're sitting on giant slicks and you have too light a flywheel (or rotating mass I should say) then you run out of revs when you launch and bogging can occur. You'll never find a really light flywheel on a drag car.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">You argued 4 pages of pure bullshit, and seem to have come to the conclusion that it's okay as long as you have a pro drag car. </TD></TR></TABLE>
Yup. I think it's pretty obvious at this point that Mike93eh2 and Zex_cool have nothing useful/pertinent/accurate to contribute.
The deceleration part doesn't matter; that's compensated for by faster shifting. The RPMs still have to drop to the same level regardless of flywheel weight.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">Since lighter FW means faster tq loss during each shift</TD></TR></TABLE>
You aren't making torque during a shift. The throttle plate is closed and no fuel is being injected.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">it appears this affects your total 1/4 time more so then the benefit of faster acceleration inbetween shifts. </TD></TR></TABLE>
Not possible.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">Another variable not yet discussed in this thread is when car is accelerating, FW is accelerating under load. Soon as clutch is engaged the FW is decelerating with comparably NO load. </TD></TR></TABLE>
Can you elaborate? I'm not following you.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boostedDA »</TD></TR><TR><TD CLASS="quote">Just curious as to WHY it's now okay to use a lightweight flywheel if you have a pro drag car </TD></TR></TABLE>
It's a pretty well known fact that drag cars need HEAVIER flywheels. I covered that on page 1 I believe. If you're sitting on giant slicks and you have too light a flywheel (or rotating mass I should say) then you run out of revs when you launch and bogging can occur. You'll never find a really light flywheel on a drag car.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">You argued 4 pages of pure bullshit, and seem to have come to the conclusion that it's okay as long as you have a pro drag car. </TD></TR></TABLE>
Yup. I think it's pretty obvious at this point that Mike93eh2 and Zex_cool have nothing useful/pertinent/accurate to contribute.
Honda-Tech Member
Joined: Jul 2006
Posts: 4,009
Likes: 0
From: missouri
Re: (Legion)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Legion »</TD></TR><TR><TD CLASS="quote">
It's a pretty well known fact that drag cars need HEAVIER flywheels. I covered that on page 1 I believe. If you're sitting on giant slicks and you have too light a flywheel (or rotating mass I should say) then you run out of revs when you launch and bogging can occur. You'll never find a really light flywheel on a drag car.
Yup. I think it's pretty obvious at this point that Mike93eh2 and Zex_cool have nothing useful/pertinent/accurate to contribute.
</TD></TR></TABLE>
go back and read this whole thread again and count how many times ive said that oem flywheels are best on a big boosted honda. thats what ive been saying this whole thread over and over. this was my whole argument!!!!! its pretty obvious youre going to use a big boosted honda for drag racing. and now youre admitting it right there above in your quote exactly what ive been saying. and you say i dont have anything useful to contribute but youre saying exactly what ive been saying.
youre a dipshit.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Legion »</TD></TR><TR><TD CLASS="quote">
It's a pretty well known fact that drag cars need HEAVIER flywheels.
</TD></TR></TABLE>
ohhh now you know that... wierd.
It's a pretty well known fact that drag cars need HEAVIER flywheels. I covered that on page 1 I believe. If you're sitting on giant slicks and you have too light a flywheel (or rotating mass I should say) then you run out of revs when you launch and bogging can occur. You'll never find a really light flywheel on a drag car.
Yup. I think it's pretty obvious at this point that Mike93eh2 and Zex_cool have nothing useful/pertinent/accurate to contribute.
</TD></TR></TABLE>
go back and read this whole thread again and count how many times ive said that oem flywheels are best on a big boosted honda. thats what ive been saying this whole thread over and over. this was my whole argument!!!!! its pretty obvious youre going to use a big boosted honda for drag racing. and now youre admitting it right there above in your quote exactly what ive been saying. and you say i dont have anything useful to contribute but youre saying exactly what ive been saying.
youre a dipshit.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Legion »</TD></TR><TR><TD CLASS="quote">
It's a pretty well known fact that drag cars need HEAVIER flywheels.
</TD></TR></TABLE>
ohhh now you know that... wierd.
* B A N N E D *
Joined: Apr 2007
Posts: 848
Likes: 0
From: SoCal, CA
Re: (Civicman86)
Don't EVEN. No need to argue, let's just go back to page one. Here's your idiotic first post:
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mike93eh2 »</TD></TR><TR><TD CLASS="quote">you dont want a lightweight flywheel on a boosted engine.</TD></TR></TABLE>
And here my first post:
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Legion »</TD></TR><TR><TD CLASS="quote">The only time a light flywheel is bad is if you run out of revs trying to launch on large slicks. This happens because your engine doesn't hold enough momentum to launch without bogging. But if that happens, I'd say running smaller slicks would be the better solution sinc</TD></TR></TABLE>
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mike93eh2 »</TD></TR><TR><TD CLASS="quote">you dont want a lightweight flywheel on a boosted engine.</TD></TR></TABLE>
And here my first post:
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Legion »</TD></TR><TR><TD CLASS="quote">The only time a light flywheel is bad is if you run out of revs trying to launch on large slicks. This happens because your engine doesn't hold enough momentum to launch without bogging. But if that happens, I'd say running smaller slicks would be the better solution sinc</TD></TR></TABLE>
* B A N N E D *
Joined: Apr 2007
Posts: 848
Likes: 0
From: SoCal, CA
Re: (mike93eh2)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mike93eh2 »</TD></TR><TR><TD CLASS="quote">go back and read this whole thread again and count how many times ive said that oem flywheels are best on a big boosted honda. thats what ive been saying this whole thread over and over. </TD></TR></TABLE>
All you've been saying over and over is how you don't understand rotational kinematics. The need for a heavier flywheel can only be determined through empirical testing, not some un-founded assumption you've made and decided to argue in favor of. Saying "big boosted hondas should use OEM flywheels" is complete bullshit. That's a blanket statement that has absolutely NO way of accounting for the actual variables that influence necessary flywheel weight, such as power-band/rev limit/wheel size/tire compound.
If I flip a coin in the air and you swear on your life that it'll turn up heads, and then it actually does happen to turn up heads, it doesn't mean you were right all along; it means you have absolutely no understanding of scientific method.
All you've been saying over and over is how you don't understand rotational kinematics. The need for a heavier flywheel can only be determined through empirical testing, not some un-founded assumption you've made and decided to argue in favor of. Saying "big boosted hondas should use OEM flywheels" is complete bullshit. That's a blanket statement that has absolutely NO way of accounting for the actual variables that influence necessary flywheel weight, such as power-band/rev limit/wheel size/tire compound.
If I flip a coin in the air and you swear on your life that it'll turn up heads, and then it actually does happen to turn up heads, it doesn't mean you were right all along; it means you have absolutely no understanding of scientific method.
Member
Joined: Apr 2003
Posts: 1,210
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From: Now in SoCal, CA, USA
Re: (Legion)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Legion »</TD></TR><TR><TD CLASS="quote">
The deceleration part doesn't matter; that's compensated for by faster shifting. The RPMs still have to drop to the same level regardless of flywheel weight.
</TD></TR></TABLE>
RPM's will drop at different rates depending on rotating mass (flywheel is part of that). Change the FW, then you change deceleration rate of the engine when you step on the clutch. That's the entire issue with using too lite of a FW on a boosted civic. When you shift, the RPM's drop below ideal power band and you have to build boost all over again.
"You aren't making torque during a shift. The throttle plate is closed and no fuel is being injected"
I never implied or mentioned making tq during a shift. I said tq loss... When you engage clutch and let off the gas, you immediately begin to lose tq (and power). The rate at which you lose tq is determined by your rotating mass attached to the crank (FW). Essentially, your FW is a torque storage device. Apply tq (step on gas) then take tq away (let off gas) and heavier FW will store (hold) tq for a longer period.
For an easy way to know what I mean, about loaded Vs unloaded FW.
-While driving your car accelerate.
-Then let off the gas and engage the clutch. Notice how fast the RPM's drop.
-Now accelerate again.
-This time let off the gas and do not step on the clutch, notice how slow the RPM's drop.
This example shows loaded Vs unloaded only in deceleration.
With clutch engaged your engine only has FW, crank, and pistons for rotating mass. This is your torque storage device. It's called inertia.
However, When the clutch is not engaged the storage device is now FW, crank, pistons, transmition, axles, tires, and even the road surface. Since the storage device is so much bigger in this case, it takes much longer to deplete the remaining torque of the engine from when you last accelerated.
Hope that helps
The deceleration part doesn't matter; that's compensated for by faster shifting. The RPMs still have to drop to the same level regardless of flywheel weight.
</TD></TR></TABLE>
RPM's will drop at different rates depending on rotating mass (flywheel is part of that). Change the FW, then you change deceleration rate of the engine when you step on the clutch. That's the entire issue with using too lite of a FW on a boosted civic. When you shift, the RPM's drop below ideal power band and you have to build boost all over again.
"You aren't making torque during a shift. The throttle plate is closed and no fuel is being injected"
I never implied or mentioned making tq during a shift. I said tq loss... When you engage clutch and let off the gas, you immediately begin to lose tq (and power). The rate at which you lose tq is determined by your rotating mass attached to the crank (FW). Essentially, your FW is a torque storage device. Apply tq (step on gas) then take tq away (let off gas) and heavier FW will store (hold) tq for a longer period.
For an easy way to know what I mean, about loaded Vs unloaded FW.
-While driving your car accelerate.
-Then let off the gas and engage the clutch. Notice how fast the RPM's drop.
-Now accelerate again.
-This time let off the gas and do not step on the clutch, notice how slow the RPM's drop.
This example shows loaded Vs unloaded only in deceleration.
With clutch engaged your engine only has FW, crank, and pistons for rotating mass. This is your torque storage device. It's called inertia.
However, When the clutch is not engaged the storage device is now FW, crank, pistons, transmition, axles, tires, and even the road surface. Since the storage device is so much bigger in this case, it takes much longer to deplete the remaining torque of the engine from when you last accelerated.
Hope that helps
* B A N N E D *
Joined: Apr 2007
Posts: 848
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From: SoCal, CA
Re: (turbosi03)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turbosi03 »</TD></TR><TR><TD CLASS="quote">RPM's will drop at different rates depending on rotating mass (flywheel is part of that). Change the FW, then you change deceleration rate of the engine when you step on the clutch. That's the entire issue with using too lite of a FW on a boosted civic. When you shift, the RPM's drop below ideal power band and you have to build boost all over again.</TD></TR></TABLE>
But the RPMs drop the same amount regardless of your flywheel weight. The RPM drop is entirely dependent on your transmission gearing. Falling out of boost is purely dependent on your powerband and gearing.
Let's say (arbitrary numbers here) you shift at 7k RPMs and the revs drop to 4k for the next gear. You make full boost at 4500, so you've fallen slightly out of boost. How does the flywheel have any effect on this at all? No matter what, you'll always be falling to 4k RPMs. And actually, since the LW flywheel lets you fall to 4k quicker, and the throttle plate is closed so no exhaust gases are being produced to spool the turbo, the LW flywheel should actually help you stay IN boost longer since the turbo shaft will retain more momentum and will be spinning faster when you engage the next gear.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">I never implied or mentioned making tq during a shift. I said tq loss... When you engage clutch and let off the gas, you immediately begin to lose tq (and power). The rate at which you lose tq is determined by your rotating mass attached to the crank (FW). Essentially, your FW is a torque storage device. Apply tq (step on gas) then take tq away (let off gas) and heavier FW will store (hold) tq for a longer period.</TD></TR></TABLE>
Yes, but the clutch isn't engaged during a shift...? The car itself is still rolling with the same momentum.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">With clutch engaged your engine only has FW, crank, and pistons for rotating mass. This is your torque storage device. It's called inertia.
However, When the clutch is not engaged the storage device is now FW, crank, pistons, transmition, axles, tires, and even the road surface. Since the storage device is so much bigger in this case, it takes much longer to deplete the remaining torque of the engine from when you last accelerated. </TD></TR></TABLE>
I guess the confusion comes from how you're using the word "engaged." I consider the clutch to be engaged when your foot is off the pedal (and the PP fingers engage the disk). It seems that you're using it the opposite manner...? At any rate, I still fail to see the relevance. This concept doesn't affect acceleration or shifting.
But the RPMs drop the same amount regardless of your flywheel weight. The RPM drop is entirely dependent on your transmission gearing. Falling out of boost is purely dependent on your powerband and gearing.
Let's say (arbitrary numbers here) you shift at 7k RPMs and the revs drop to 4k for the next gear. You make full boost at 4500, so you've fallen slightly out of boost. How does the flywheel have any effect on this at all? No matter what, you'll always be falling to 4k RPMs. And actually, since the LW flywheel lets you fall to 4k quicker, and the throttle plate is closed so no exhaust gases are being produced to spool the turbo, the LW flywheel should actually help you stay IN boost longer since the turbo shaft will retain more momentum and will be spinning faster when you engage the next gear.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">I never implied or mentioned making tq during a shift. I said tq loss... When you engage clutch and let off the gas, you immediately begin to lose tq (and power). The rate at which you lose tq is determined by your rotating mass attached to the crank (FW). Essentially, your FW is a torque storage device. Apply tq (step on gas) then take tq away (let off gas) and heavier FW will store (hold) tq for a longer period.</TD></TR></TABLE>
Yes, but the clutch isn't engaged during a shift...? The car itself is still rolling with the same momentum.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">With clutch engaged your engine only has FW, crank, and pistons for rotating mass. This is your torque storage device. It's called inertia.
However, When the clutch is not engaged the storage device is now FW, crank, pistons, transmition, axles, tires, and even the road surface. Since the storage device is so much bigger in this case, it takes much longer to deplete the remaining torque of the engine from when you last accelerated. </TD></TR></TABLE>
I guess the confusion comes from how you're using the word "engaged." I consider the clutch to be engaged when your foot is off the pedal (and the PP fingers engage the disk). It seems that you're using it the opposite manner...? At any rate, I still fail to see the relevance. This concept doesn't affect acceleration or shifting.