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Discussion Starter · #1 ·
I have a 94 Camaro Z28 with the 7.5" 10 bolt. I want to change from the stock 3.55s to 4.11s for drag racing. Can I just slap a new ring and pinion in, or do I have to upgrade carriers? Will the physical gear size be too different for what's in there? Any advice would be appreciated
 

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1979 Chevrolet Malibu 496-TH400-9" (cruiser). 1992 Chevrolet S10 355-700r4-7.625" (daily driver).
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Both of those gear ratios use the same series carrier.

The ring and pinion gears are machined very precisely to size. As such, keeping the shims in order should get you close to or right where you need to be with the new gears.
 

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yes if you are going from dirt to drag i wouldent want to jinx you it is fun. you will make changes as needed if you injoy it. its addictive you just keep wanting to go faster.
 

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yes im sorry to say you will break it. i have pushed many off the track breaking in the burn out box. but they would come back with a updated rear diff most of time with a ford 8.8 rear diff. its a buget swap if you do some checking around you will find out what 8.8 will work best for you.
 

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Discussion Starter · #8 ·
I don't mind upgrading the whole rear end of the car, but I just don't have the time or money before the upcoming race. I'll just have to hope it'll hold up for one day. After the race, I'll definitely look into a 9" or something similar, but right now I just need to know that simply swapping ring and pinion will technically work. Bone stock LT1 with a 4l60e and a 100 shot of nitrous. Nothing too extreme for right now, and if I do decide to go faster yet, the whole drivetrain will probably be swapped out for stuff that's easier and stouter to build.
 

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3.55 would no be a stock gear ratio in that car. the 3 series carrier fits gears of 3.23 and numerically higher. verify the current gear. the stock diff is probably an Auburn which is not real durable for track use.
 

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355 would be kinda like the middle of the road for st-strip. as for the Nos dont leave with the nos i never did liked getting imbarresed get the car out of the hole then the Nos you stand a mutch better chance of making a good pass if you leave with NOS diff want want make it. if so your odds are very low. just use a timer or a button. just incase your wondering I have 40 years in this sport nobody runs a 7.5 here at this track for that very reason. it is the wink link
 

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Since it's in a Camaro, it may be a 7.625" with larger pinion head bearing and 28-spline axles instead of 26. Should last a little longer than a basic G-body 7.5". Then again, maybe the 7.625 didn't appear until the late 90s.

A long time ago I bought a car that had a 7.5 with 3.42 gears behind a 350 and Muncie M20. It never broke, even though I abused it knowing I was going to replace it.
 

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3.55 would no be a stock gear ratio in that car. the 3 series carrier fits gears of 3.23 and numerically higher. verify the current gear. the stock diff is probably an Auburn which is not real durable for track use.
I'm not even sure 3.55 was a choice. Seems like it was 3.23, 3.42, 3.73.

I'd like to see a photo of the diff cover.
 

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If your going to do this do it once 31 spline 9", or 8.8.

Or look at toyota rear axles with 3rd members most people dont even consider them. But most are strong with a good aftermarket.
 
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