How much will gears knock off in the 1/4?
09-15-2004, 12:45 AM
#1
Registered User
Thread Starter
Join Date: May 2001
Location: Reno, NV
Posts: 97
How much will gears knock off in the 1/4?
I know this is about a Stang but please bear with me. Look at my mods in the sig. I am planning gears soon. I am wondering how many tenths and mph, 3.73, 3.90, 4.10, and 4.30 gears will give me in the 1/4 mile with my current mods? 3.73 gears are great for top speed and a daily driver. 4.30 gears are best for the dragstrip. I was just wondering what the difference would be between all these gear ratios at the strip. Anybody know? Thanks in advance.
09-15-2004, 09:34 AM
#2
Registered User
Join Date: Jun 2004
Location: Behind a Desk in OKC
Posts: 118
Re: How much will gears knock off in the 1/4?
I have heard gears knock off UP TO .5 of the 1/4. So my guess would be somewhere between .2 and .5 off.
If you have a 5-speed I would go with 4.10's or 3.90's. If you have an auto, I probably wouldn't go over 3.73's.
I wouldn't get 4.30 gears unless you have a 5 speed AND you motor is modified to rev really high (7000rpm+). Traction would really become a big issue too. On a stock/near stock motor, 4.30's would probably slow you down.
Just my opinion.
If you have a 5-speed I would go with 4.10's or 3.90's. If you have an auto, I probably wouldn't go over 3.73's.
I wouldn't get 4.30 gears unless you have a 5 speed AND you motor is modified to rev really high (7000rpm+). Traction would really become a big issue too. On a stock/near stock motor, 4.30's would probably slow you down.
Just my opinion.
09-15-2004, 03:45 PM
#3
Registered User
Join Date: Dec 1999
Location: MD
Posts: 2,022
Re: How much will gears knock off in the 1/4?
You're 0-2. Not only is this not about an F-body, but it's in the wrong forum too. 
Dyno'd the car? For optimum acceleration performance gear the car to cross the line at peak HP in 4th gear. But generally 3.73s or 4.10s would be a good choice. 4.10s would put you right around 105 MPH in 4th gear at 5500 RPM (near your peak HP). IMO 4.30s would be too much gear. They're better suited to a DOHC car.
Dyno'd the car? For optimum acceleration performance gear the car to cross the line at peak HP in 4th gear. But generally 3.73s or 4.10s would be a good choice. 4.10s would put you right around 105 MPH in 4th gear at 5500 RPM (near your peak HP). IMO 4.30s would be too much gear. They're better suited to a DOHC car.
Last edited by Marc 85Z28; 09-15-2004 at 03:49 PM.
09-15-2004, 09:27 PM
#4
Registered User
Thread Starter
Join Date: May 2001
Location: Reno, NV
Posts: 97
Re: How much will gears knock off in the 1/4?
Originally Posted by Marc 85Z28
You're 0-2. Not only is this not about an F-body, but it's in the wrong forum too.
Dyno'd the car? For optimum acceleration performance gear the car to cross the line at peak HP in 4th gear. But generally 3.73s or 4.10s would be a good choice. 4.10s would put you right around 105 MPH in 4th gear at 5500 RPM (near your peak HP). IMO 4.30s would be too much gear. They're better suited to a DOHC car.
Dyno'd the car? For optimum acceleration performance gear the car to cross the line at peak HP in 4th gear. But generally 3.73s or 4.10s would be a good choice. 4.10s would put you right around 105 MPH in 4th gear at 5500 RPM (near your peak HP). IMO 4.30s would be too much gear. They're better suited to a DOHC car.
09-16-2004, 03:54 PM
#5
Registered User
Join Date: Dec 1999
Location: MD
Posts: 2,022
Re: How much will gears knock off in the 1/4?
Originally Posted by Steve Y
I heard that you are supposed to gear the car to be near redline in 4th gear at the traps for max 1/4 mile power. My redline is 6000 rpm, my rwhp peak is 5000 rpm. I have a 1 to 1 4th gear and should trap about 103 right now.
Regardless of what others say, you can gain a few MPH from better gearing. Optimal gearing should add another 2-3MPH to your traps.
For a targeted 105MPH trap, and a peak HP occuring around 5000RPM, 3.73s would be perfect. All this is assuming a 26" diameter tire (stock diameter).
Steeper gearing would cause you to either shift into 5th gear, or more likely spin past your peak HP. Not only that but 4.10s add more mechanical torque to the wheels than 3.73s, increasing any traction problems you might have.
Last edited by Marc 85Z28; 09-16-2004 at 03:57 PM.
09-16-2004, 07:30 PM
#6
Registered User
Thread Starter
Join Date: May 2001
Location: Reno, NV
Posts: 97
Re: How much will gears knock off in the 1/4?
Originally Posted by Marc 85Z28
Not redline per se, but peak HP. Most engines are capable of revving past their peak HP RPM. I can rev my engine to 6500 if I want. But its pointless, as my peak HP occurs at 5500RPM.
Regardless of what others say, you can gain a few MPH from better gearing. Optimal gearing should add another 2-3MPH to your traps.
For a targeted 105MPH trap, and a peak HP occuring around 5000RPM, 3.73s would be perfect. All this is assuming a 26" diameter tire (stock diameter).
Steeper gearing would cause you to either shift into 5th gear, or more likely spin past your peak HP. Not only that but 4.10s add more mechanical torque to the wheels than 3.73s, increasing any traction problems you might have.
Regardless of what others say, you can gain a few MPH from better gearing. Optimal gearing should add another 2-3MPH to your traps.
For a targeted 105MPH trap, and a peak HP occuring around 5000RPM, 3.73s would be perfect. All this is assuming a 26" diameter tire (stock diameter).
Steeper gearing would cause you to either shift into 5th gear, or more likely spin past your peak HP. Not only that but 4.10s add more mechanical torque to the wheels than 3.73s, increasing any traction problems you might have.
Thread
Thread Starter
Forum
Replies
Last Post
dbusch22
Forced Induction
6
10-31-2016 11:09 AM