c5_ls1_6spd

iTrader: (-1)

thinking of adding 4.10s out back. what is the top speed of a c5 6spd with these gears?

WayneE

Theoretically, you can run 253mph in 6th gear with a 295/35 18 rear tire, 4.11 gears and a 6700 rev limit. More realistically, you can reach 171mph with that same combo in 5th gear. IMO, if you're into top end, don't go with 4.11s.

Do you drag race? What size tire? With that same combo, you're limited to 127mph in 4th gear, which is where you try to end up at the end of the track. So, unless you're using a tall drag tire, you're pretty limited in your 1/4 mile speed.

Sigforty

I am going with 3.90s cause I think the 4.10s will be a little to much especially since I DD the car.

MGorman

It all depends how many RPM you can turn. An otherwise stock C5 would do about 155-157 in 5th gear with 4.10’s. I don’t think it would pull any faster in 6th.

The more you mod and increase the power and RPM range the faster you’ll go. WayneE is correct. If you spin the motor to 6700 RPM in 5th you’ll be going about 171 MPH. If you have enough power you should be able to exceed 171 MPH in 6th gear.

97C5ENVY

If you're looking for top speed don't get a gear change, but if you're looking to be quicker off the line and have a car that's super fun to drive then yes get 4:10's.

FYI - I'm putting down 430 rwhp with 4:10's AND running 345/19/30's out back (rev limited @ 6800) and i have traction issues in 1st and 2nd. I can even break the tires loose at 40 mph by just smashing the go pedal.

NEVRLIFT

Just remember that the 4:10s in C5 Coupe are equal to about 3:90s in the Z06.

pontiac

iTrader: (4)

soo what gear in a zo6 for a daily driver???

keep in mind I drive a 4.11 locker with a spec 3 clutch and a light *** fligh wheel, and big cam rite now. the gear is probly going to be the only mod.

also do vette's rear ends wine like a f body when you change the gear

WayneE

I'm not sure I follow you. The C5 Z06 has steeper tranny ratios than the coupe from the factory, so any gearing change will be multiplied in the Z06. So if you put 4.11s in both a coupe and Z06, the Z06 would have steeper gears because of the transmission.

dwalker011

iTrader: (1)

Do the FRC's and Z06's share the same transmission ratios? I just bought a 99 FRC with a P1SC and am looking into putting gears into it but, don't really know to much about them. What do you guys think is a good ratio for a split between street/drag and highway/high speed? I see gears for sale in the classified section all the time. How do I know which ones will fit my rear? I installed a set of 3.73s on my friends 02 Mustang and the difference was amazing and the install was pretty easy.

~JOSHUA

iTrader: (92)

I have 4.10's in my 420 rwhp Firehawk. They're dead quiet. If you have an f-body you should use Motive gears. The pitch they cut the gear with has a lot to do with the noise... and find an installer that kows his way around a diff.


Honestly, a buddy with an identical (modded and cosmetically) Firehawk with 3.42's feels about the same as mine with 4.11's. Mine pulls past him in 4th gear, but I have more work through 1st and 2nd balancing traction.


I'm going to a 3.23 or 2.73 12-bolt when I add the Procharger (and 300 hp) and later this year.


On a C5 I'd honestly heep the 3.42's and add power.