Gear Question - Not Your Typical One
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Race Director
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From: Are you fat because you're lazy or lazy because you're fat? San Jose, CA
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St. Jude Donor '09
Gear Question - Not Your Typical One
I've been thinking of doing gears, either 3.90 or 4.10s for my 01 coupe. While I understand how they give you great gains on the butt dyno, especially with throttle respone, I have some other questions about them.
They allow the engine to get into it's powerband quicker, but doesn't this also mean that you'll be shifting more frequently. Wouldn't this then mean that you are spending less time "under power", which can't be a good thing?
They allow the engine to get into it's powerband quicker, but doesn't this also mean that you'll be shifting more frequently. Wouldn't this then mean that you are spending less time "under power", which can't be a good thing?
Melting Slicks
Joined: Sep 2006
Posts: 2,041
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From: Rockford Illinois
I've been thinking of doing gears, either 3.90 or 4.10s for my 01 coupe. While I understand how they give you great gains on the butt dyno, especially with throttle respone, I have some other questions about them.
They allow the engine to get into it's powerband quicker, but doesn't this also mean that you'll be shifting more frequently. Wouldn't this then mean that you are spending less time "under power", which can't be a good thing?
They allow the engine to get into it's powerband quicker, but doesn't this also mean that you'll be shifting more frequently. Wouldn't this then mean that you are spending less time "under power", which can't be a good thing?
Race Director
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From: Marlton. Increasing performance one speeding ticket at a time! NJ
Upgrading the gears makes the tires spin slower. The reduction in RPM comes with a corresponding increase in torque at the wheels. So if you go from 3.42 to 4.10, thats ~20% increase. So your RPMs will be 20% higher to go the same speed, and the torque at the wheels will be 20% higher. Overall, you haven't changed power since power=torque x rpm.
But you do run out of top end since the engine has to rev higher to go equivalent speed.
You absolutely will have to shift more freqently. In fact, going too low can hurt 1/4mile times if you have an extra shift in the run.
Sure is fun to roast the tires, though
But you do run out of top end since the engine has to rev higher to go equivalent speed.
You absolutely will have to shift more freqently. In fact, going too low can hurt 1/4mile times if you have an extra shift in the run.
Sure is fun to roast the tires, though
Pro
Joined: Feb 2003
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From: Ankeny IA
With as much as gears cost in these cars, I'd be sure it's what you want long term. I had planned on going with 3.90's in this car, but with it's current power level I can't use 1st gear as is. Perhaps after I switch to Nitto R2's I'll change my mind. But for now the last thing I need is lower gearing.
Thread Starter
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From: Are you fat because you're lazy or lazy because you're fat? San Jose, CA
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St. Jude Donor '09
Good point, I had thought of this as well. I'd hate to spend $1500-2000 on a set of 3.90s or 4.10s, then do H/C or FI with over 450rwhp and have no traction through the 1st 3 gears.
Melting Slicks
Joined: Nov 2002
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From: Jamison Pa
St. Jude Donor '11-'25
What Traction?
I've got 4:10's and I like them. I can use 6th gear without going a gizillion miles an hour. With the 3:42's the car would drone in 6th below 75mph.
BTW, I've got 460 rwhp and you just need to be careful when taking off in any gear below 3rd.
Bob K.
BTW, I've got 460 rwhp and you just need to be careful when taking off in any gear below 3rd.
Bob K.
