Just Installed 3.90 Gears
02-23-2015, 11:35 PM
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Just Installed 3.90 Gears Well I've always installed gears in all my camaros. All have been 4.10's. This time around I went with 3.90 gears. Must admit I'm very happy with my decision. I think there the perfect gear for an M6 car. I get decent traction in first and pulls harder in 2nd with good traction. After I install LT's and get a Tune I'll get a bit less traction but I'm sure still manageable. My car had 3.23 gears before so going to 3.90 made a noticeable difference. Feels like the car wants to jump a bit when I let of the clutch and better bottom and mid range as well.
02-26-2015, 03:46 PM
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Just noticed driving on the freeway today. Knowing ofcourse my mph is off that's a given after a gear swap, my issue us thus is not a normal M6 Tranny gearing at all. It feels like the gearing is way too short. At 80mph on the highway, again knowing I'm not going 80mph I'm going probably 70 or less I'm at 2600rpms. Which for me is way too high. I've done plenty of 4.10's and with those I was never that high. Not sure whats going on. Maybe I need to reserve judgment till I get the computer tuned but I have pretty good idea that its just to high of an rpm. I might be at 2400rpms at 65mph in 6th.
02-26-2015, 06:32 PM
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Ya just the basics Flowmaster Muffler, exhaust cut out, intake, pulley, 52mm TB, TB Bypass, Aluminum Driveshaft, No cat, 160 Thermo, 3.90 Gears. Has a garbage tune. LT,S and Ypipe are waiting till I find a good exhaust shop or mechanic to install.
02-26-2015, 07:02 PM
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the only year m6 that came with 3.23's was 93 so unless you have that year the car should have had 3.42's unless someone swapped the rear. 93 also had different trans ratios which could account for the rpm if its a 94 on up you should have standard ratios.
i have 3.90s and spin 1900 at 80, fwiw you could verify speed with an app on your phone
i have 3.90s and spin 1900 at 80, fwiw you could verify speed with an app on your phone
02-26-2015, 07:22 PM
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Thanks for the response, car was originally an A4. Prior owner converted the tranny to an M6. The motor was a 93 but he pulled the motor out of a 96 he said. The car is actually a 93 Camaro Z28.
the only year m6 that came with 3.23's was 93 so unless you have that year the car should have had 3.42's unless someone swapped the rear. 93 also had different trans ratios which could account for the rpm if its a 94 on up you should have standard ratios.
i have 3.90s and spin 1900 at 80, fwiw you could verify speed with an app on your phone
i have 3.90s and spin 1900 at 80, fwiw you could verify speed with an app on your phone
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02-26-2015, 09:37 PM
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Ya he did a lot of work on it. All gaskets are new and all suspension bushings are poly. So who know at this point what year tranny it is but man 5th and 6th seem really short for only having 3.90's.
02-27-2015, 07:49 AM
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They do make a little noise but barely. There great gears noticed bottom and mid range the car really woke up. I can't wait to install the LT's, once I find a good shop.
02-27-2015, 08:20 AM
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You can try playing around with this here to get an idea where your at. http://www.f-body.org/gears/ With 4.10s in 6th I'm 70mph/2000rpm, I need to get rid of them now tho with the boost.
02-27-2015, 09:55 AM
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That helped, I put in tire size and rear ratio. Its funny I'm pretty good at knowing when driving these cars not being told what gears it has. I told my friend I was positive this car had 3.23 gears before changing them to 3.90's and was right. This whole thing that I'm experiencing now has confused me. I'll definitely check it out on Monday with a speed app. Soon computer will go in for a tune when I get my other car from the body shop
You can try playing around with this here to get an idea where your at. http://www.f-body.org/gears/ With 4.10s in 6th I'm 70mph/2000rpm, I need to get rid of them now tho with the boost.
02-28-2015, 08:03 AM
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My 4.10, 4.11, 3.90's have all been just as quiet as my stock 3.42 gear in my 10bolt. The only time i have had problems making a rear quiet is with Richmond gears. That holds true fir my 9" 3.89 gear to. Although i bought it used and didn't set them up myself it does have Richmond gears so i don't think it was the person who set them up as the pattern looks fine......just noisy gears.
02-28-2015, 08:58 AM
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I was talking to the guy who set up my rear and I was s bit surprised he told me Richmond folded or bought out. I will admit though even though I'm not hearing much noise it was a terrible experience at that shop. Took them plenty of cars with new people I'm seeing work there it just was not the same.
02-28-2015, 09:20 AM
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I wanna say I had 4:10 yukons in my 95 m6 TA. They were fairly quiet. Next I had 4:10 Richmonds in my 96 M6 Z28 and they hummed like crazy. So annoying. Now I have motive 3:90s in my M6 00 SS. The motives are the best by far. I must say I enjoyed 4:10s over 3:90s. I feel like every gear pulled harder and 6th was even more useable.