400 rwhp LS1, 1/4 ET Gain from 3.07 to 3.91 gears???
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400 rwhp LS1, 1/4 ET Gain from 3.07 to 3.91 gears???
Ive been running these 3.07 gears in my c4 vette because they came stock and i never got around to buying new ones...plus its around $300 for a ring/pinion and i put a th350 /w 3800 converter in to handle the nitrous HP (approx 600-650 rwhp)...Butttttttt should i just go ahead and spring for the gears and swap to the 3.91's??? or would i only see a tenth or two...
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Re: 400 rwhp LS1, 1/4 ET Gain from 3.07 to 3.91 gears???
The higher gears would give you in time about your own estimate. If you want to go faster, I personally prefer the higher gear. With the higher gear, you have to deal with traction issues off line and speed adjustment for proper speed. Also, with the higher gear, your shift points will most likely be adjusted. If at track, keep car in 3 gear across the line for maximum speed and time. Cheers....
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Re: 400 rwhp LS1, 1/4 ET Gain from 3.07 to 3.91 gears???
On motor on those 28's what does the car 60ft now, high 1.6's?
I think the gear would help somewhat, I'm thinking 2 tenths and 2 mph. I think you might see 2-3 mph, that's what I have seen for gear swaps in LS1's with stock 4L60E's with 3.23's, but I'm not sure if you might see only a tenth or two reduction in ET. The LS1 likes rpms, and likes big converters. Is your T350 a 2.48 first gear?
I think the gear would help somewhat, I'm thinking 2 tenths and 2 mph. I think you might see 2-3 mph, that's what I have seen for gear swaps in LS1's with stock 4L60E's with 3.23's, but I'm not sure if you might see only a tenth or two reduction in ET. The LS1 likes rpms, and likes big converters. Is your T350 a 2.48 first gear?
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Re: 400 rwhp LS1, 1/4 ET Gain from 3.07 to 3.91 gears???
What speed are you trapping now on the bottle? I'm guessing that much spray on a light weight car could have your trap speed as high as 140 mph. Make sure you don't run out of gear with 3.91s. Depending upon your tire size and whether you can lock the converter, 3.55 or 3.73 may be a better choice.
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Re: 400 rwhp LS1, 1/4 ET Gain from 3.07 to 3.91 gears???
I have the stock th350 first which i think is a 2.48.... And yea i run 28" tires which grow to approx 29-29.5" down the track.. which would be equivilant to a 25-26" tire with 2.70's or so ???
right now it 60 ft's 1.8's and it full hooks, its almost impossible to do spin because it just kind of leaves and takes a while to get in the rpm's in 1st gear...
right now it 60 ft's 1.8's and it full hooks, its almost impossible to do spin because it just kind of leaves and takes a while to get in the rpm's in 1st gear...
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Re: 400 rwhp LS1, 1/4 ET Gain from 3.07 to 3.91 gears???
Ah 1.8's, I was gonna initally say 1.7's but I thought your car might be light enuff to 60ft better.
Your 3.07's + 2.48 gear + 28's are like no gear at all. I bet your car would hook great on a 26" drag radial and go 1.6's.
I'd probably contemplate a gear if the car is mostly at the track. If you are mostly streetracing on the gun I would leave it I'm sure it deadhooks on the street?
Your 3.07's + 2.48 gear + 28's are like no gear at all. I bet your car would hook great on a 26" drag radial and go 1.6's.
I'd probably contemplate a gear if the car is mostly at the track. If you are mostly streetracing on the gun I would leave it I'm sure it deadhooks on the street?