Guys with 3.91 gears in a 6spd manual
 

I would like to know a couple of things before I do this:

1) I understand that the powerband will shift. How does it feel when on the highway and you want to downshift to pass? Do we lose a lot of top end power after the gear install in favor of low end power?

2) Has anybody done a 0-60 run? This is the area i'm trying to improve upon rather than the quarter mile. I understand I should be able to get off the line quicker but will lose top end which is fine with me. But I'm wondering if there is a real improvement in 0-30, 0-60 etc.

Any negative feelings with the gears? Is 1st gear still useable? Will I be needing to shift at a really low speed now?

Thanks
J

What is your power?

You don't lose any top-end power (or any power, for that matter). You'll just get through your powerband quicker and you'll feel like you have more torque everywhere. I still think it's the best bang-for-your-buck mod out there.

If you're N/A, first gear will be perfectly useable. If you add a PD blower, it gets a bit dicey, but scary fun (I used to have 4.10s, before I grenaded them).

I guess he no savvy? :smm7:

This. You will have an equivalent torque gain of approximately 13% or 54.6 lb.-ft. of torque at all RPMs.

Sweet. I am normally aspirated with an intake and tune.

But does the zero-60 improve?

What size drag radials or slicks?

0-60 improves if you get traction. Overall I like the 3.91's. On the highway the car feels much lighter and I don't see a reason to downshift. It picks up faster now

How much does it affect the overall top speed? :happy0180:

How much will it help in the 1/4m or 1/2m over the stock 3.45's? I'm cam only

Helped me on the 1/4 with a .2 faster and two mph gain from my previous run on a worst 60'. That was my first time out there with the gears and I only done two passes that night. Only downfall I can think off is 4th gear ends at 140mph. I didn't shift into 5th as I thought that was fast enough.

5th can do 155 with plenty of room to go

3.91 is great if you like spinning tires when you have a supercharger. lol

Does 5th gear still have any power in it or will it just bog down? Isn't that a cruising gear?

I have had both 3:91 and 4:10 in my M6 car loved them both. If I had to choose a favorite 4:10 would be the ones I liked best. Turned 11:72 with those gears, Bolt On's with slicks and skinnies.

:thumb: