Stock rear end?

[Zdufty]

Hi there! I want to swap a 350 drivetrain out of a 81 chevy pickup into my 1983 cutlass. The new drivetrain is a 350/350 combo. The current 231 v6 isnt cutting it. My question is - How strong are the stock rear ends? Which one do I have (assuming they only put one type in with the 231 v6? Also, which trans is my automatic three speed? Thanks!

 

[magoo_oner]

More than likely you have a 7.5 rearend and it should hold up with that motor and my next question is where are u tryna go with this car if its just gona be a daily driver you should be good if your gona build up the motor for 1/4 mile or sumn or locking it up alot or donut car id ditch that rearend but dont get me wrong those 7.5 will take a beating I ran mine in my 83 wagon for.months behind my 383 th350 with a stall and I thought it would actually the day I swaped to a 8.5 I tryed to brake it but nope one legged that b*tch all down my block haha

 

[DRIVEN]

How strong are the stock rear ends? Which one do I have? Also, which trans is my automatic three speed?

Probably strong enough for your 350 if not blatantly abused. It's a 7.5" with a ratio likely in the mid 2.XX range. Your transmission should be a TH200 unless someone replaced it with a TH350. That's fairly common since they are a direct replacement.

...and welcome to the forum. Post up some pics and specs. Let's see what you're working on.

 

[Zdufty]

Thanks for a replys guys. Its just a reliable year round driver. Im tired of the weak *ss 3.8, and while the sbc will not be a monster by any means, its gonna be much more powerfull all around than this 231 could ever dream of being. Hah, I almost wanna do something nuts, like take the 383 out of my 69 elcamino and throw it in there, or do a 454 build for it. But, alast, Ill probobly just do the 350/350 build.

 

[Zdufty]

http://www.gbodyparts.com/product_info. ... 19c6a37780

Those look like some solid new mounts. Something tells me im gonna be using this website alot for this swap.

 

[Intragration]

Yep, most likely a 2.41 if your car was a TH200, and maybe 2.73 to 3.08 if it's a 2004R. You can check it pretty easily by spinning the driveshaft. Should hold up fine behind the 350, but I don't think you're going to be happy if they're 2.41s. Great for the salt flats, terrible for street fun.

 

[Zdufty]

Ok, that's no big deal. I can just swap a set of lower gears (numerically higher) into the rear end. That would probably allow it to turn easier with the motor anyway, because the gears aren't so steep, so it would be even easier on the stock rear end.

This is really coming together. Im so excited.

 

[beeterolds]

Don't run super sticky tires and you'll be fine.. They're actually hit and miss in terms of reliability.. My axle has seen low 13s from my 403, lots of stop light to stop light action with the 455, countless burn outs.. and it has never missed a beat.. yet.. 😛

Ive seen other guys powering up winding hills with mildly built engines and next thing they kno the car aint moving!! ring gear ate the pinion!!!

Mileage is also a factor...