best crank for most power
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From: Columbus, Ohio, U.S.A.
best crank for most power
starting an all motor project. been out of the game a while and was wondering what crank stroke and weight is making the most power for:
b18c
bored to 2.0 liters
Crower max light rods
cp pistons 12.5:1
last i check it was stock, but things change right?
b18c
bored to 2.0 liters
Crower max light rods
cp pistons 12.5:1
last i check it was stock, but things change right?
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From: winnipeg, manitoba, canada
Re: best crank for most power (ITRtist)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ITRtist »</TD></TR><TR><TD CLASS="quote">starting an all motor project. been out of the game a while and was wondering what crank stroke and weight is making the most power for:
b18c
bored to 2.0 liters
Crower max light rods
cp pistons 12.5:1
last i check it was stock, but things change right?</TD></TR></TABLE>
if you want to run a bigger stroke than stock your going to have to either remove or modify the oil squirters so they won't get hit.
b18c
bored to 2.0 liters
Crower max light rods
cp pistons 12.5:1
last i check it was stock, but things change right?</TD></TR></TABLE>
if you want to run a bigger stroke than stock your going to have to either remove or modify the oil squirters so they won't get hit.
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Re: best crank for most power (ITRtist)
98-101mm strokes have made over 300+ in race only B blocks. I dont see a problem making 250-260 on a big b street engine. If its a street set up your looking for, go with a 98mm stroke (dont be afraid to go big), 85.5mm bore and 11.7:1 compression.
12.5:1 will force you to back timing out which will limit power potential. Less compression allows you to be a bit more agressive with timing when using pump gas which normally results in a bit more power through out the band.
12.5:1 will force you to back timing out which will limit power potential. Less compression allows you to be a bit more agressive with timing when using pump gas which normally results in a bit more power through out the band.
FSAE
Joined: Jan 2002
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From: Drinking Beer, UT
Re: best crank for most power (Hardt)
We run a 98mm crank in our methanol motor. Revving to 8500 bearing wear is substantial after 20 passes.
95-98mm, I would limit revvs to 8000 if you want to keep bearings for at least 30k miles.
91mm cranks are a good balance between power and longevity.
95-98mm, I would limit revvs to 8000 if you want to keep bearings for at least 30k miles.
91mm cranks are a good balance between power and longevity.
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From: nothing is real unless it is observed
Re: best crank for most power (ITRtist)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ITRtist »</TD></TR><TR><TD CLASS="quote">starting an all motor project. been out of the game a while and was wondering what crank stroke and weight is making the most power for:
b18c
bored to 2.0 liters
Crower max light rods
cp pistons 12.5:1
last i check it was stock, but things change right?</TD></TR></TABLE>
If you already have the block sleeved, rods and pistons bought you are stuck with what you have.
If you increase the stroke you will need to
a. shorten the rods
b. reduce the compression height of the piston
c. increase your deck height
On the WD40 2L shoot out the 87mm crank beat out the others, the bore seemed to be beneficial than the stroke although they were COMPLETELY different setups.
b18c
bored to 2.0 liters
Crower max light rods
cp pistons 12.5:1
last i check it was stock, but things change right?</TD></TR></TABLE>
If you already have the block sleeved, rods and pistons bought you are stuck with what you have.
If you increase the stroke you will need to
a. shorten the rods
b. reduce the compression height of the piston
c. increase your deck height
On the WD40 2L shoot out the 87mm crank beat out the others, the bore seemed to be beneficial than the stroke although they were COMPLETELY different setups.
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From: South Florida
Re: best crank for most power (Natural Aspirations)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Natural Aspirations »</TD></TR><TR><TD CLASS="quote">
On the WD40 2L shoot out the 87mm crank beat out the others, the bore seemed to be beneficial than the stroke although they were COMPLETELY different setups.</TD></TR></TABLE>
Link please, sounds interesting...
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 92TypeR »</TD></TR><TR><TD CLASS="quote">We run a 98mm crank in our methanol motor. Revving to 8500 bearing wear is substantial after 20 passes.
95-98mm, I would limit revvs to 8000 if you want to keep bearings for at least 30k miles.
91mm cranks are a good balance between power and longevity.</TD></TR></TABLE>
Would you say a 92 mm crank would be fine to run on a weekend street car?
On the WD40 2L shoot out the 87mm crank beat out the others, the bore seemed to be beneficial than the stroke although they were COMPLETELY different setups.</TD></TR></TABLE>
Link please, sounds interesting...
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 92TypeR »</TD></TR><TR><TD CLASS="quote">We run a 98mm crank in our methanol motor. Revving to 8500 bearing wear is substantial after 20 passes.
95-98mm, I would limit revvs to 8000 if you want to keep bearings for at least 30k miles.
91mm cranks are a good balance between power and longevity.</TD></TR></TABLE>
Would you say a 92 mm crank would be fine to run on a weekend street car?
B*a*n*n*e*d
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From: Hessian Aggression
Re: best crank for most power (Hardt)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hardt »</TD></TR><TR><TD CLASS="quote">98-101mm strokes have made over 300+ in race only B blocks. I dont see a problem making 250-260 on a big b street engine. If its a street set up your looking for, go with a 98mm stroke (dont be afraid to go big), 85.5mm bore and 11.7:1 compression.
12.5:1 will force you to back timing out which will limit power potential. Less compression allows you to be a bit more agressive with timing when using pump gas which normally results in a bit more power through out the band.</TD></TR></TABLE>
x2
12.5:1 will force you to back timing out which will limit power potential. Less compression allows you to be a bit more agressive with timing when using pump gas which normally results in a bit more power through out the band.</TD></TR></TABLE>
x2
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From: Southern California, U.S.A.
Re: best crank for most power (neo_)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by neo_ »</TD></TR><TR><TD CLASS="quote">
Link please, sounds interesting...</TD></TR></TABLE>
http://www.importtuner.com/bseriesshootout/
My next ITR engine is going to be sporting a 92mm crank. Shooting for 260 Dynojet. My 89mm GSR motor is making 240+ Dynojet.
Link please, sounds interesting...</TD></TR></TABLE>
http://www.importtuner.com/bseriesshootout/
My next ITR engine is going to be sporting a 92mm crank. Shooting for 260 Dynojet. My 89mm GSR motor is making 240+ Dynojet.
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Re: best crank for most power (neo_)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by neo_ »</TD></TR><TR><TD CLASS="quote">Would you say a 92 mm crank would be fine to run on a weekend street car?</TD></TR></TABLE>
I would say that a 98mm crank would be fine as well. It really comes down to the assembly. Id recomend running either a fluidampr or ATI harmonic balancer, Id also recomend running bearing clearances a little on the loose side (.0020 mains and .0022 rods). With looser clearances your going to shorten the life of the engine a bit but it will be making more power lose than it will tight or at OEM rec. I also like the idea of running smaller rod journals, it keeps bearing speeds down, also a plus.
Bearing failure or premature wear isnt always because of the crank or size of the stroke. There are many factors involved, tuning, detonation, clearances crank stability "crank walk", etc.
The bigger the stroke, the bigger the engine, the more torque the engine will make. Torque is what propels the car down the track. Two engines in identical chassis', both making 270whp, 1 making 180 torque, the other making 201 torque. You tell me which has the potential to go faster?
If your worried about wear and longevity, you probably shouldnt be looking into a full build. Id say stick with OEM for a street car. Youll get the longevity your looking for with OEM.
I would say that a 98mm crank would be fine as well. It really comes down to the assembly. Id recomend running either a fluidampr or ATI harmonic balancer, Id also recomend running bearing clearances a little on the loose side (.0020 mains and .0022 rods). With looser clearances your going to shorten the life of the engine a bit but it will be making more power lose than it will tight or at OEM rec. I also like the idea of running smaller rod journals, it keeps bearing speeds down, also a plus.
Bearing failure or premature wear isnt always because of the crank or size of the stroke. There are many factors involved, tuning, detonation, clearances crank stability "crank walk", etc.
The bigger the stroke, the bigger the engine, the more torque the engine will make. Torque is what propels the car down the track. Two engines in identical chassis', both making 270whp, 1 making 180 torque, the other making 201 torque. You tell me which has the potential to go faster?
If your worried about wear and longevity, you probably shouldnt be looking into a full build. Id say stick with OEM for a street car. Youll get the longevity your looking for with OEM.
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Re: best crank for most power (Hardt)
To add more to my last post, You can achieve a 1.42 r/s ratio w/ a 97 crank in a B block. F23's, B20A's and a few others have had r/s ratios in the 1.44-1.45 range out of the box from Honda, all of which have gone 200K+ miles with out any problems.
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From: not riding any bandwagons in, massachusetts, usa
with that short of a rod ratio i dont see why it cant be pushed into the 12:1 compression range.. the piston will be pulling away pretty damn fast at any RPM.
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Re: (mike_belben@yahoo.com)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mike_belben@yahoo.com »</TD></TR><TR><TD CLASS="quote">with that short of a rod ratio i dont see why it cant be pushed into the 12:1 compression range.. the piston will be pulling away pretty damn fast at any RPM. </TD></TR></TABLE>
correct, same theory applys with big strokes and boost.
correct, same theory applys with big strokes and boost.
B*a*n*n*e*d
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Re: best crank for most power (92TypeR)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 92TypeR »</TD></TR><TR><TD CLASS="quote">We run a 98mm crank in our methanol motor. Revving to 8500 bearing wear is substantial after 20 passes.</TD></TR></TABLE>
Does methonal contamination of the oil have anything to do with the bearing wear? Or are you guys changing the oil after every pass and using good stuff like Torco SR-5.
Does methonal contamination of the oil have anything to do with the bearing wear? Or are you guys changing the oil after every pass and using good stuff like Torco SR-5.
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Re: best crank for most power (Don Lackey)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Don Lackey »</TD></TR><TR><TD CLASS="quote">
Does methonal contamination of the oil have anything to do with the bearing wear? Or are you guys changing the oil after every pass and using good stuff like Torco SR-5.</TD></TR></TABLE>
Good point
Does methonal contamination of the oil have anything to do with the bearing wear? Or are you guys changing the oil after every pass and using good stuff like Torco SR-5.</TD></TR></TABLE>
Good point
FSAE
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From: Drinking Beer, UT
Re: best crank for most power (Don Lackey)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Don Lackey »</TD></TR><TR><TD CLASS="quote">
Does methonal contamination of the oil have anything to do with the bearing wear? Or are you guys changing the oil after every pass and using good stuff like Torco SR-5.</TD></TR></TABLE>
Yes, we are using Torco, Bisi recommended it at the beginning of 2006, we've found that Torco works the best with both our turbo and methanol drag car. First inspection after the first event showed no bearing wear, then we swapped cams to BC5's and started revving another 800rpms over the Pro2's, second inspection 2 events later showed noticeable wear. System was flushed after every event, and more often than not, we were forced to change the oil between passes due to leaks etc...
It is my belief that there is a relationship between piston speed and bearing wear.
Does methonal contamination of the oil have anything to do with the bearing wear? Or are you guys changing the oil after every pass and using good stuff like Torco SR-5.</TD></TR></TABLE>
Yes, we are using Torco, Bisi recommended it at the beginning of 2006, we've found that Torco works the best with both our turbo and methanol drag car. First inspection after the first event showed no bearing wear, then we swapped cams to BC5's and started revving another 800rpms over the Pro2's, second inspection 2 events later showed noticeable wear. System was flushed after every event, and more often than not, we were forced to change the oil between passes due to leaks etc...
It is my belief that there is a relationship between piston speed and bearing wear.
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From: not riding any bandwagons in, massachusetts, usa
the relationship is more specifically focused on oil wedge pressure and bearing wear. its difficult to isolate what creates the excessive wedge pressures, since increase in rpm brings:
*additional harmonics
*additional torsions of the crankshaft
*increased compressive and tensile forces
*increased surface speeds
*more dry wipes of the journal across the bearing per run (when the wedge pressure is too high.)
you may wish to try a thicker oil just to see the results in your frequent teardowns. ive read that oil pump pressure is irrelevant to oil wedge pressure. radial clearance, side clearance and viscosity were the largest factors that i recall.
*additional harmonics
*additional torsions of the crankshaft
*increased compressive and tensile forces
*increased surface speeds
*more dry wipes of the journal across the bearing per run (when the wedge pressure is too high.)
you may wish to try a thicker oil just to see the results in your frequent teardowns. ive read that oil pump pressure is irrelevant to oil wedge pressure. radial clearance, side clearance and viscosity were the largest factors that i recall.
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From: Pittsburgh, PA
Re: best crank for most power (Natural Aspirations)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Natural Aspirations »</TD></TR><TR><TD CLASS="quote">
On the WD40 2L shoot out the 87mm crank beat out the others, the bore seemed to be beneficial than the stroke although they were COMPLETELY different setups.</TD></TR></TABLE>
I have had really good results with my last two 87mm builds.
On the WD40 2L shoot out the 87mm crank beat out the others, the bore seemed to be beneficial than the stroke although they were COMPLETELY different setups.</TD></TR></TABLE>
I have had really good results with my last two 87mm builds.
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Re: best crank for most power (jdm_ef9)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jdm_ef9 »</TD></TR><TR><TD CLASS="quote">
I have had really good results with my last two 87mm builds.</TD></TR></TABLE>
TQ>HP
Most of you guys put too much emphasis on HP numbers and overlook the numbers that count, torque. HP is simply a measuring tool derived from an equation of torque and RPM.
Modified by Hardt at 5:33 PM 1/9/2007
I have had really good results with my last two 87mm builds.</TD></TR></TABLE>
TQ>HP
Most of you guys put too much emphasis on HP numbers and overlook the numbers that count, torque. HP is simply a measuring tool derived from an equation of torque and RPM.
Modified by Hardt at 5:33 PM 1/9/2007
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From: modesto, ca, usa
Re: best crank for most power (Hardt)
very true, trq #'s are the key we made only 256 but 190+ ft lbs in our all motor crx street ca the recently went 11.1 on the first pass down the track! i have lost 30 fwhp but kept the same trq #'s and still ran the same times!
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From: Sherman Oaks, CA, United States
Re: best crank for most power (Hardt)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hardt »</TD></TR><TR><TD CLASS="quote">TQ>HP
Most of you guys put too much emphasis on HP numbers and overlook the numbers that count, torque. HP is simply a measuring tool derived from an equazion of torque and RPM. </TD></TR></TABLE>
Just to throw this out there.
http://www.vettenet.org/torquehp.html
Yeah, I know, its a Corvette site. Some things are thankfully universal though.
To quote the article I linked:
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by http://www.vettenet.org/torquehp.html »</TD></TR><TR><TD CLASS="quote">
It is better to make torque at high rpm than at low rpm, because you can take advantage of *gearing*.
</TD></TR></TABLE>
And
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by http://www.vettenet.org/torquehp.html »</TD></TR><TR><TD CLASS="quote">
The Integra GS-R, for instance, is faster than the garden variety Integra, not because it pulls particularly harder (it doesn't), but because it pulls *longer*. It doesn't feel particularly faster, but it is.
</TD></TR></TABLE>
Most of you guys put too much emphasis on HP numbers and overlook the numbers that count, torque. HP is simply a measuring tool derived from an equazion of torque and RPM. </TD></TR></TABLE>
Just to throw this out there.
http://www.vettenet.org/torquehp.html
Yeah, I know, its a Corvette site. Some things are thankfully universal though.
To quote the article I linked:
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by http://www.vettenet.org/torquehp.html »</TD></TR><TR><TD CLASS="quote">
It is better to make torque at high rpm than at low rpm, because you can take advantage of *gearing*.
</TD></TR></TABLE>
And
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by http://www.vettenet.org/torquehp.html »</TD></TR><TR><TD CLASS="quote">
The Integra GS-R, for instance, is faster than the garden variety Integra, not because it pulls particularly harder (it doesn't), but because it pulls *longer*. It doesn't feel particularly faster, but it is.
</TD></TR></TABLE>
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From: not riding any bandwagons in, massachusetts, usa
i agree, but torque is a product of cylinder pressure x crank throw.
not trying to knock jdm_ef9, but if you make more TQ on less stroke, i consider the situation to be one where the attempts made using more stroke that didnt produce as much torque, were not optimal.
if the stroke goes up with the same cylinder pressure, the torque should too. if it didnt, cylinder pressure declined.. the question is why?
not trying to knock jdm_ef9, but if you make more TQ on less stroke, i consider the situation to be one where the attempts made using more stroke that didnt produce as much torque, were not optimal.
if the stroke goes up with the same cylinder pressure, the torque should too. if it didnt, cylinder pressure declined.. the question is why?