Ive got an 83 cutlass supreme 3.8 l v6 231ci with the 2.41 gearséNon posi, and what i believe may be the th200 transmission. Im wanting to beef up the gears, just wondering if the trans and rear end with hold, or do need to swap out the rear end as well.
Gear swap help
- Thread starter Cutlass83Supreme
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I would imagine you'll be fine. I put 3.42's in my car with a real beefed up 350 and a 700r4 and havent had a problem with the 7.5" rear..
The 7.5 will hold up for most people. The first things that break are the differential gears. Broken teeth swirl around and eat posi springs etc. One thing to consider is that an automatic will help buffer right foot abuse. The TH200 will be the first thing to die with more power. Start with a TH350. They're fairly cheap. But, swapping gears becomes expensive: $200 gears, $450 posi, $150 installation kit (bearings seals, etc.) labor $400. You'll have a grand in there fast. So...consider what your plans for the future are. If you will stick with a non-overdrive, stick with a 3.08 and higher if you'll spend much time past 55 MPH. Consider 3.08 and a 700R4 and you'll have the best of both worlds because they were designed to get a big car off the line with a steep 3.06 first gear. Not so nice if you have 3.42 or 3.73 or 4.10, since you'll blow through 1st quite fast.
Actually the spider gears explode first and take out the gears, ask me how I know. The 3.8 will probably barely spin any gears, even 3.42's, will last forever if done right. A complete Monte SS rear is another option.
I had my 3.42's put in, posi completely rebuilt, axles spun to make sure they're straight. All new seals for $150 from a local guy who specializes in differentials. He does them for pulling trucks and drag cars.
My problem is trying to find a monte carlo that hasnt been ripped apart.... I live in Canada, and on a island to add to difficulty. Would ideally be a street car that has some get up, if things stay as planned.
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