I have decided to get the 4.10s thanks for all the help. Could you guys post some good links to some gear packages?

 

Would this be a good set?

http://www.slponline.com/view_product.asp?P=64046

 

wouldn't higher gears also take away from top end?

 

Yes.

They do reduce the top speed.

But an M6 car hits top speed in 5th gear not 6th. So there is room for more gearing. I forget evactly what it is but if you do the math, 6000RPMs with 3.42's is like 240MPH top speed in 6th gear. With 4.10's its down to around 170 or 180 I think.

Really though how many are going 170 or 180, and for that matter how many have the power to go 180???

And if you have that much power, you wont have 4.10s anyways cause it would make 1st and possibly second obsolete at WOT as they would jsut sit there and bake the tires.

Gears are fine for the right applications.

4.10's are EXCELLENT for a bolt on, or MILDLY cammed car. After that, traction starts to get scarce. That and you are shifting too many times in a 1/4 mile run and that also hurts your ET.

 

i got mine from byunspeed. Under 200 shipped for gears and install kit. Im getting them installed tomorrow. I went with 3.73 because i have an automatic.

 

with 3.42s i was going thru the traps in the 1/4 in the top of 3rd. 3.42s in 3rd is effectively a 4.33 ratio. now i go through the traps in the top of 4th. the 4.10 is very flexable in an M6 car because they work with stock motor'd cars equally well as with heads/cam combos. with the heads cam combo you rev higher and make more hp. because of this you run more mph, the 4.10s at 6400rpm with a 26" slick is right at 118 mph, which is around what most 400rwhp h/c combos run for 1/4 mile mph.

 

Yea but they also have a tendency to burn through first and second. They need the slicks to get any kind of traction. And stickies kill the stock rear after some hard launches.

So if your going to try and make over 400RWHP, I personally wouldnt go with 4.10's. Its too much gear for too much power. Well, Inless you get a 12 bolt heheh. Then Id imagine they would be fantastic.

 

ive found that the 4.10s are easier to launch part throttle, i run ET streets every day. if you dont drop the clutch WOT on the rev limiter they are fine. several of my buddies have run mid 11s w/ heads/cam packages and 4.10s making over 400rwhp on slicks. if you dont drive like an animal its fine. my buddies car went from running 8.40s@86mph to 7.50s@94 mph 1/8 mile with his 400rwhp heads/cam lt1 just by swapping 4.10s for the 3.42s in his M6 car. they dont like to run without gear.

 

4:10's will make 1st gear useless unless you have some really sticky tires or suspension mods. My LT1 had 4:10's and punching it form a roll would produce alot of smoke and no traction. I put 3:73's in my LS1 and its perfect.

Its a subjective thing though.

 

I thought Motive gears were not good, nor Richmond. I was directed to either GM, Strange, Superior, etc.
For a six speed, 4.10s are good with the six speed versatility. Just my .02

 

Dont forget to have your PCM tuned for it. EFI needs to know everything to work effectively and harmoniously.

 

I thought all they do to the PCM when you get gears is recalibrate the speedo.

 

not hijacking the thread or anything, but this is the same thing i was thinking for my m6 car. i really don't want a gear as steep as 4.10, so i'm thinking 3.73 as a go-between. what are your rpm's at 65 mph with the 3.73?

 

If I was getting gears, I would get 3.73's. But I plan on making alot more horsepower down the road, so its pointless to upgrade gears if I am going to be replacing the rear end. When I get a new rear, I most likely will be getting 3.73's or 3.42's. This will be on a heads/temporary cam until its a forged 383 supoercharged. With alot of horsepower you dont want much more than stock if its on the stock rear end. Youll need stickies, and thatll just blow the rear out. Spend the money somewhere else inless you hate the gears you have now that bad.

 

at 100MPH I run like 2100 RPM's