3.90's Anyone?
 

I'm looking for a little bit more low end torque. I don't feel i'm utilizing all my power with my stock 3.42's. Does anyone have any input on a 3.90?

With a cam 3.90s are a very popular gear choice. I know I have them.

So the 3.90s are worth the change from 3.42? I take it you need a sticky tire to hook up 3.90 with the mn12 tranny, but you see a good gain? Also how is it installing gears in z06 as compared to an fbody or something? Thanks, I had 4.10s in my ls1 and my stang so I am used to steep gears anyways.

You need sticky tires to hook up with the stock gears. 3.90s just put you into the powerband sooner, they actually make the car easier to launch than with the stock gears. I had 3.90s in my C6, it made a nice difference.

I'm running 3.90's in the rear at the moment, couldnt be happier :)

Chris

I run 3.90's and this is the way the car should have come from the factory.

I had the whole rear chukc swapped as I wanted hardened shafts as well. Sticky tires were required at the track stock now for the street I had to add them once I hit 450 rwhp. The car was not safe on anything but a drag radial at that power level on the street.

I'm well above 450rwhp and while I admit you need a reasonable sense of afermath in the first 3 gears I still think they are perfect. I run 295x35 BFG KDW 2's on the back.

I have 3.90s and they are tons of fun. With almost 500 rwhp they will blow the BFG KDs off in the first 3 gears.

can you buy the gears alone or has everyone bought the dte diff? I just dont know how I feel about spending 1300 on gears :(

Do not just get gears at least get a hardened output shaft for the weak side. Should be 1650 unless prices have changed.

3.90's an auto trans & a blower......WOOHOO!!!!!!

Pewtavert...your car must move! Any video of it

I have 3.90s with a 3800 stall. Currently working on fixing traction problem the 402 and F1-R have created :D

Keith

I just got my DTE Stage IV with 3.90's this week, going in the car in the spring. :)

http://members.cox.net/vettenuts/after.jpg

If you have an m12 (z06 tranny) your 3.42 is very close to a 3.90 in a standard vette (m6 tranny). I would suggest no more than a 3.73 for you cause a 3.90 is a crap load of gear changing. If you must have a 3.90 then expect frequent gear changes and forget road racing. If this is a daily driver I really would not go any more than 3.73. I would also not look anywhere other than DTE. They offer many different choices and all their rear diffs are THE BEST out there.
I have a 3.90 in a standard tranny and it is a handfull. I tach to red line in first at about 35 to 40 mph, so you see that the lower gears are not going to be used very long. I can easily start off in second and go right to fourth with no problem. That being said, sixth gear is no longer a cruse gear but something that has a little torque to it. You will also loose a little HP on the dyno with stronger gearing. Good Luck!

Hmm...Interesting thoughts about the 3.73. It's a weekend warrior but I am a road racer at heart. I grew up racing open wheel cars. I'm not so much of a drag racer but I sure do like to smoke people on a 3rd gear pull. It's hard to have the best of all worlds....

Get the 3.90s and don't even think twice about it. I had 4.10s in a stock bolt on C5 Z06 and it was a RIOT and I went road racing with no issues, except faster acceleration and faster shifting, which always makes more FASTER FUN!! :drive: :chug: :drive:

With that big cam you have you are LOSING some low end grunt and the 3.90s will be JUST WHAT the Doctor ordered to make up for it and then some!! DO IT, DO IT! :judge: :judge:

Thanks. No video just yet, the Procharger is only a few months old and I am waiting for the warm weather, just around the corner. :drive: The last time out at the track I ran a 11.96 @ 116 mph and that was before the Supercharger. I can't wait to see what she can do now. :)