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Switched from 3.15 to 3.31 today,does that require a updated tune?

5K views 16 replies 9 participants last post by  stigma 
#1 ·
I just had 3.31's installed today-

I realize that i can select 3.31 as my axle on the sct-tuner but does the tune have to be updated from Bama to tweak shift points because of the change?

Thanks in advance for thoughts-
 
#2 ·
That's an interesting gear change. I think you will be fine as long as the gear ratio is adjusted on the Tuner and re-uploaded, otherwise the shifts will be off.

Curious, with such a minimal gear ratio change, what were you looking to accomplish?
 
#4 ·
Why no 3.73's? Just change the gear setting in your tuner and your good to go.
 
#5 ·
Thanks for all the reply's......as far as why the minimal change? It was Free,i swapped axle for axle with a friend who is getting rid of his car Monday-

I have already made the adjustment on the SCT and will hopefully make it to the track soon-

Thanks again to all-
 
#10 ·
11.30 Wow- that's Great- What size wheels and tires do you have in the rear or your car? And what tune are you running?

Thanks-
 
#11 ·
Thanks. I run the Weld RT-S 15x10 wheels in back with a M/T 295/55-15. I tune my own car. For the autos though Mike Rousch at Mid Atlantic Performance is widely regarded as one of the best at tuning these autos.
 
#12 ·
Nope. You can either have us update the gear ratio for you within the tune or you can just select the proper gear ratio in the settings of the SCT device. Either way you'll be in good shape!

Hope this helps. Let us know if the Bama team can be of any assistance!

-Dan
 
#13 ·
Thank you Dan.... I made the change and all is good- The sct-x4 showed a shift at 6,802 rpm so i am happy with that-
 
#15 ·
From 3.15 to 3.31 rear gear-

After i made the gear switch i also replaced my axle back muffler deletes with the factory mufflers and look at the outcome-

Here is a link to the video of the G-Tech run....

Keep in mind that the ET is always +/- 1 tenth and the mph is always 5-6 mph too fast-

https://www.dropbox.com/s/elxkn6653z...619_203411.3gp

I will be at the track next Friday and hopefully by then i will have drag radials and hook up-

That was using the 5.0 SCT-Tune....
 
#16 ·
After i made the gear switch i also replaced my axle back muffler deletes with the factory mufflers and look at the outcome-

Here is a link to the video of the G-Tech run....

Keep in mind that the ET is always +/- 1 tenth and the mph is always 5-6 mph too fast-

https://www.dropbox.com/s/elxkn6653z...619_203411.3gp

I will be at the track next Friday and hopefully by then i will have drag radials and hook up-

That was using the 5.0 SCT-Tune....
It shows "Invalid link"
 
#17 ·
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