Advice needed on Differential and Gear setup.

[SVECobraR]

Hey guys i just installed the FTBR bushings in my bolt on 99 cobra this weekend and i'm deciding to upgrade my diff while i'm still at it. I'm currently running the stock 28 spline traction lok with 4.10's but have spare 31 spline axles sitting at home.

So my question is. Which differential do you guys prefer between the Torsen T2R and the Wavetrac? Any personal experiences with the latter would be nice as i've already read a lot about the T2R's.

Also i've been thinking about gearing up to 3.73s. The 4.10's are a boat load of fun on the street but give me nothing on the highway and are very limited on the roval at california speed way and little to short for buttonwillow. Does anyone have experience with a N/A cobra with 3.73's or even 3.90's? Everywhere you check online people say 4.10's or bust for N/A, which is cool for drag racing or street driving but i don't think its optimal for road racing.

Opinions are appreciated.

Thanks in advance.

 

[WPBcobra]

I have a N/A cobra and 4:10s are the way to go. I have had 373s but they suck on the tight turns coming out of the hole.

 

[SVECobraR]

What about the fact that your speeds above 100 are really limited.

 

[WPBcobra]

In my last cobra with stock trans I had no probs with speeds over 100. I was still able to stay in 4th at sebring and at homestead raceway with banking i still fine in 5th.
With my AI car i just added 410s and i have a RR 5th so not sure what the rpms will be but the rest of the guys down here are running them and the only track they topped 5th was daytona right be for turn 1

 

[wheelhopper]

You may also want to consider the Detroit Trutrac. I have heard good things about them as well.

 

[cobra916]

i have a cammed mach 1.. had 430s.. hated them..way to short.. now i have 373s.. they work great..much better for roll racing.. which is alot like road racing... they are about perfect for me..but 355s might be better to keep the longevity of the motor.. the track is about having fun..not about hitting the best time you can.. i would do 355s if i were you.. our motors rev limiter might be 7k but they no way should be going past 6500..

 

[cobra916]

http://www.svtperformance.com/forums/new-edge-cobras-51/782808-gear-thread-end-all-gear-threads.html

 

[racebronco2]

Hey guys i just installed the FTBR bushings in my bolt on 99 cobra this weekend and i'm deciding to upgrade my diff while i'm still at it. I'm currently running the stock 28 spline traction lok with 4.10's but have spare 31 spline axles sitting at home.

So my question is. Which differential do you guys prefer between the Torsen T2R and the Wavetrac? Any personal experiences with the latter would be nice as i've already read a lot about the T2R's.

Also i've been thinking about gearing up to 3.73s. The 4.10's are a boat load of fun on the street but give me nothing on the highway and are very limited on the roval at california speed way and little to short for buttonwillow. Does anyone have experience with a N/A cobra with 3.73's or even 3.90's? Everywhere you check online people say 4.10's or bust for N/A, which is cool for drag racing or street driving but i don't think its optimal for road racing.

Opinions are appreciated.

Thanks in advance.

I base my gear ratio on the speeds of the track i open track at. I like to be topped out in a gear at the end of most of the straights. I had 4.10's before at cal speedway, they worked well but i had to shift into 6th on the front straight but it would slow me down too much.

At cal speedway what was you highest speed and what gear on the
front straight?
before the braking zone at Turn 3?
Before turn 5?
The back straight?
Complex?

At buttonwillow what speed and gear (of course depends on cc or cw but lets say cw)
front straight before sunrise?
I-5?
bus stop?
telladega?
Phil hill?
dog leg before star mazda?
Short straight away before sunset?

You cannot have your gears optimized for all track but you can try and get it optimized for most of the turns.