C6 re-gearing?

Anyone have any experience with results after swapping in a lower 1st & 2nd gear kit into their C6? I run a relatively heavy car 3400lbs at ahigh altitude local track. I cannot go deeper in the rear that 3.89's w/ 28" tire due to often running on a nos shot. I ordered a kit to drop 1st gear down to a 2.71 and second down to a 1.53. Hoping this will improve the 60' na and help get the car up and moving better in the thin air. Thoughts???

My thoughts:

After making enough power with my ride, I have found that the low gearset is a hinderance. the 1-2 shift occurs before the 60 foot clock, and traction has been a problem.

Without the spray, running 10.80's to 11.0's, the low gearset combined with the 3.89 gear and 29.5" tire was great, though.

Greg

I agree with greg here in my truck when I was lacking on power the gear set help alot but now that I have a motor making power and torque I think the wide ratio set is causing me traction issues. This is in a f-150 4x4 mud truck

That will also give you a big spread between 2nd and high, If you running into high gear before the end. It will hurt your gear recovery. Also you can add air with the N.O.S.

Additionally, i have been thinking a lot about the wide ratio gearset recently because I'm gonna be switching to an E4OD this winter. The E4OD gearset is what gets installed in the C6 to make the wide tatios in the C6.

I think I'm gonna put rollerized C6 first and second gearsets in the E4OD, in essence making it a close ratio 4 speed auto.

Greg

Thanks for the replies guys.
So far, traction hasn't been an issue. My mid 1.6's 60' I'm pretty sure has been the car's lack of a decent converter (3600 TCI 10"). Running the tires at 12-13psi, I can footbrake it to 2800rpm max before it pushes. The higher I am able to foot brake it (track prep) the harder the car seems to leave, lifting the front tires a bit and dead hooking nice and straight. I shift at 6600rpm. When I hit it with a 100shot .005 seconds after WOT and then ramp up the remainder of the nos shot it does the same just lifting the front tires that much higher and more agressively. So I definately plan on stuffing a real converter in there and figured I might try this C6 gearing idea and see if the car responds favorably. I'm really torn. I had tried 4.33's in the rear before and the car definately liked them on the motor but they were just too steep for bottle. If I could run 10.8's up here na I'd be pretty content. Heck that's a high 9 na at a low altitude track with a solid launch. I'm not interested in getting a license or cert.

I've got the E4OD set in mine and have learned to hate it....I put em in when i still was running a 550hp 429. Did they work then? I dont know cause i never ran that engine w a reg. c6. But no matter what i do now w. my 545 it wont hook. Next time i get it too the track it'll have stock gearing back in it. Like everyone has said, you're shifting into 2 super quick and then have a huge split into high gear. Matter of fact, i accidently launched my 4100lb truck in second gear and only lost .04 in 60ft and .10 in the quarter and it still spun. I think its a waste of time to put em in in my opinion unless it's some kind of stockish application.

I run a 4100# 64 galaxie with only the first gear planetary it picked my up 4 tenths. That is with a hydralic camed 466 with tunnel ram. I think the heavy cars like them alot more.
B Hoover

Weight may be a factor, but my car weighs 4160 lbs.... the low gearset works great off the spray running high 10.80's. But on the spray that low gearset just gives traction issues.

Greg

I kinda think both arguments have their points.

The lower gear is certainly going to give you more of a challenge getting the thing to hook up but its likely going to help a heavier car, esp one like mine running at altitude in the thin air to get up and moving. Looks like a couple of the responses were from guys running pickups which start out at a disadvantage in the traction department when you stuff a powerful BBF in them.

Greg's combo is fairly similar to my own I believe. My NOS setup is on a progressive controller however. So far my ride hooks decent for what it is probably because I've been running a low stall converter, the close ratio gearing of the C6, reduced performance at altitude, and a little luck with the CalTracs. Even when it hangs the tires a few inches it really don't feel like it leaves all that violently like many I've seen including Greg's.