i am sending my OEM ITR flywheel away with my new rotating assembly to get balanced. i was thinkin about telling the machinist to take a few pounds off while hes at it. good idea?? if so how much weight off would be desireable?? my current setup is b18c5 block, forged 9:1 mahle pistons, scat rods, ITR head with toda B cams(skunk2 pro1's soon). im in the process of gettin my turbo kit together but ill be running approx. 15 psi. and shooting for around 300-350whp. if i get more then sweet


Modified by ITR-EKcoupe at 11:26 PM 7/30/2008

 

anyone???? i need to know as i am takin it to my machinist today..

 

keep the weight where it is. you dont need to worry about it as you do not have a N/A anymore

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tony413 &raquo;</TD></TR><TR><TD CLASS="quote">keep the weight where it is. you dont need to worry about it as you do not have a N/A anymore </TD></TR></TABLE>

add more, get some traction.

 

I'm running 9.5 lbs (16lbs Stock) exedy flywheel in my EK4 and i'm still wondering why honda didn't do this OEM, because it's just better ALL THE TIME!)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jeryjohn &raquo;</TD></TR><TR><TD CLASS="quote">I'm running 9.5 lbs (16lbs Stock) exedy flywheel in my EK4 and i'm still wondering why honda didn't do this OEM, because it's just better ALL THE TIME!)</TD></TR></TABLE>

less is not always better.

 

no joke, I'm ditching my light fly and going back to an oem one. I am falling out of boost too bad..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jeryjohn &raquo;</TD></TR><TR><TD CLASS="quote">I'm running 9.5 lbs (16lbs Stock) exedy flywheel in my EK4 and i'm still wondering why honda didn't do this OEM, because it's just better ALL THE TIME!)</TD></TR></TABLE>

I'd say they did not do it so their cars would be more "driveable" for the average person. However, I like my 12Lbs flywheel - not too heavy but not too light and still driveable.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by pcguy760 &raquo;</TD></TR><TR><TD CLASS="quote">

I'd say they did not do it so their cars would be more "driveable" for the average person. However, I like my 12Lbs flywheel - not too heavy but not too light and still driveable.</TD></TR></TABLE>

exactly you need the spinning mass at high rpms to "lessen" the blow between gears. if it were possible i would like a 18-20lbs flywheel, but oh well

 

I know WHY they have it the way they do its just that i don't find ANY problems with my 9.5lbs flywheel it's just better! always!!!!, uphill, downhill, cruising, Driving hard....etc
and if you're falling out of boost i'd say it' something else other than the flywheel, ingnition timing more likely or maybe even cam timing.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jeryjohn &raquo;</TD></TR><TR><TD CLASS="quote">I know WHY they have it the way they do its just that i don't find ANY problems with my 9.5lbs flywheel it's just better! always!!!!, uphill, downhill, cruising, Driving hard....etc
and if you're falling out of boost i'd say it' something else other than the flywheel, ingnition timing more likely or maybe even cam timing.</TD></TR></TABLE>

no i would think about what tranny im using first. LS on a vtec motor =

its not that your falling out of boost (if you have a good matched turbo) its that you are dropping to many rpms between shifts and losing time.

 

i run one of fadanza's lightest 7.5 of 8 whatever it is in my c1 SC. and falling out of boost? heard of wide open throttle shifts?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by powerneedy &raquo;</TD></TR><TR><TD CLASS="quote">i run one of fadanza's lightest 7.5 of 8 whatever it is in my c1 SC. and falling out of boost? heard of wide open throttle shifts?</TD></TR></TABLE>

you have a SC

 

duh but i have had a turbo setup prior to this with the same setup hence the whole 2 step thing i speak from experience

 

It is not the total wight of the flywheel that matters it is the inertia.. The ferther out on the flywheel the weight is the more inertia effekt you get.. If the weight is in the center it doesn´t matter.. You have to look at how the flywheel is designed not how much it waighs..

I like the one pice flywheels in cromoly..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by The sweed &raquo;</TD></TR><TR><TD CLASS="quote">It is not the total wight of the flywheel that matters it is the inertia.. The ferther out on the flywheel the weight is the more inertia effekt you get.. If the weight is in the center it doesn´t matter.. You have to look at how the flywheel is designed not how much it waighs..

I like the one pice flywheels in cromoly..</TD></TR></TABLE>

WTF kind you explain that any dumber i just got confused.

the reason you want a higher weight flywheel is that the inertia keeps the engine rpms higher between shifts. a very light flywheel is good on race cars because it increases acceleration and is more sensitive, so when you let off the gas rpms drop more. a drag race is a test of acceleration so a light flywheel would be geat. thats not the case for a roadcar where you want a heavier flywheel

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tony413 &raquo;</TD></TR><TR><TD CLASS="quote">WTF kind you explain that any dumber i just got confused.

the reason you want a higher weight flywheel is that the inertia keeps the engine rpms higher between shifts. a very light flywheel is good on race cars because it increases acceleration and is more sensitive, so when you let off the gas rpms drop more. a drag race is a test of acceleration so a light flywheel would be geat. thats not the case for a roadcar where you want a heavier flywheel </TD></TR></TABLE>

x2 that was pretty messed.

whats the stock weight of an ITR flywheel?? my machinest took 2.5 pounds off. he said he could take more off but i opted against it as id like to hook up. im no motor pro but it makes sense, the harder it is to get spinning the more traction you get in the beginning of the revs. also does flywheel weight affect torque at all?? youd think so as it carrys momentum.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ITR-EKcoupe &raquo;</TD></TR><TR><TD CLASS="quote">

x2 that was pretty messed.

whats the stock weight of an ITR flywheel?? also does flywheel weight affect torque at all?? youd think so as it carrys momentum.</TD></TR></TABLE>

the ITR flywheel is about 14-15lbs and a gsr is around 18lbs.

a flywheel is nothing more than a energy storage device from the engine to tranny.
when you change the weight you change how fast energy is transfered at a given speed.
lighter = quicker acceleration
heavier = slower acceleration
acceleration and speed are two different things though

 

exactly yes you'll find that you have to give it more gas to maintain the same cuise speed that is why OEM usually weighs more to help with highway fuel efficiency and make it more drivable for the average person (harder to stall due to the heavier flywwheel to keep the revs going)

 

I have an 8lb, revs drop a little too fast for me, i shift slow though, i am a lay back kind of person, even when i race lol, who makes a good 12lb unit?

 

I have a 12 pound ACT flywheel and I like it. Not to light, not to heavy, I think it's a good wieght for a boosted car.

 

I love light FW's on cars with rediculously-long gears like D-series, since you don't have to wait an hour to rev-match. When you shift fast yet have to blip the throttle, that's too light IMO.

You could ask them to shave a little off, but static weight isn't always the biggest issue. An 8lb chromoly FW will feel heavier than a 8lb aluminum job, since a higher % of weight is near the lip. Just make sure all edges are deburred to remove ALL stress risers - shattered FW's are DANGEROUS.

 

i wonder: what if you used a slightly heavier flywheel and had some method of electromechanical control to declutch the flywheel and re-engage it at a more desirable time?

So, say you spend the energy to spin a 20lb flywheel up to 7000rpm and then shift. When you declutch the transmission, the friction and pumping losses in the engine cause it to slow down. When you release the clutch and engage the new gear, you've lost a thousand rpms or more.

What if, instead, the flywheel declutches from the motor at the same time as the transmission clutch? The crankshaft can freewheel within the flywheel hub and has effectively lost 20lbs of rotating mass, so revs fall quickly, BUT the flywheel is still spinning and losing energy at a slower rate. So instead of losing that flywheel inertia to engine losses, you re-engage the flywheel once the new gear is selected and you get a small boost of power as the flywheel energy is dumped back into the drivetrain. You could even add flywheel energy by capturing energy during engine braking.

I've seen the concept before but in the form of a spinning armature used to capture energy during braking, and used to generate current for an electrical motor upon acceleration. This idea would be more mechanically rooted.

I don't know... just pie in the sky but this thread made me think of that possibility.

 

So to understand this right, a 12 lb FW will accelerate faster than a stock GSR, but be less streetable due to revs dropping faster? How much faster in the 1/4 are we talking? Even a tenth?

 

i would like to add, it's a bit trickier to launch with a lighter Flywheel