Brettinator

97 Z28 M6, 3:42 stock gears. Considering 3:73 or 4:10 gears. The 4:10 sounds better to me but I'm worried about losing all the top end speed and fuel mileage, although I am told that 5th and 6th are overdrive gears anyway. Feedback needed, thanks.

LT1derful

4.10s are my choice. And besides, you'd still be getting 84mph @ around 2500 RPMs in 6th...so, not that big of a difference. You ain't gonna run outta top end at the track. And, to me, the .31 increase from 3.42 to 3.73 just isn't worth the time and money.

People differ on this subject, so make the decision yourself; you arent' going to suffer any massive top end loss or gas mileage dips like people think. And, as I've found at the track, those 3.42s just won't pull a good 60'.

Brettinator

thanks LT1derful, ThunderRacing gave me some insight on the 4:10's as well, including operation throught the powerband. I'll definitely be doing 4:10's

MYT30TH

4:10's are The way to go in an M6 you won't be sorry

IrocManiac

With an M6 I'd say go 4.10s all the way. 6th gear is deep enough I don't think you'll see much mpg drop off at 70mph...

Brettinator

thanks for all the replies I'm SOLD

LT1derful

Get the Motive...the Richmonds whine a little more, and I hear that they aren't as strong as the Motive...and, the MOtive will generally be cheaper.

Brettinator

yeah I found the Motive at ThunderRacing.com I'll get em there I think.

sp528

What issues, if any have those with 4.10's ran into concerning traction? I was under the impression that with the stock tire size 4.10's make traction seem like a joke.

LT1derful

That's what people who can't drive will tell you.

kgkern01

I heard 4.10's aren't as strong and can break in a stock 10 bolt in drag racing especially with drag radials, but what about with soft launches on street tires? Also what about with autocross/road racing as far as strength? I am also considering a 4.10/Torsen diff upgrade.

Brettinator

I've yet to hear they were not strong enough. Generally when you get down into low 11's a bigger axle is a must.

robb4964

If you go to gearsareus.com you can het an eaton posi setup for 325 dollars just tell them you saw it on e bay with that buy it now price .I just bought 410's for my car with the eaton setup from there and it goes in this week . I was just going to go with the 410'2 alone but i know 4 people who have broke the stock rearend at the track . If i was you I wouldnt gamble and i would go ahead and buy it . Its like an insurance policy good luck and enjoy your 410's

kgkern01

I've heard the Torsen diff's are better for autocross/road racing than a clutch type diff. I don't plan on drag racing much, if I do, it will be on street tires with a somewhat easy launch, would be more interested in the MPH than ET on a drag strip. I plan on building my car up for handling, which is why I want to go with a Torsen.