Whats a good year to search JY for a 350 for? I know that some years have better 350 (w31 or 30) but chances of finding one of them are slim to none. Im just wondering what years and model old put in a 350. gonna swap out my 260....also whats the best tranny to combo that. I have searched but havent gotten a year that i have seen at the local JY.


Thanks
80v8cutlass

 

68-72 are the best, then 73-76 have good solid blocks but large combustion chambers in the head. That is OK when matched to the Speed Pros, but not with a big dish replacement. The 73-76 heads need a little work on the exhaust side. 77-80 350 are the worst, IMO, and are identified by the "3A" on the head. Windowed webs and crappy heads. Also, a 403 will bolt right in, available in late 70s vehicles. It will have a "4A" head.

 

I alot of rear end work have to be done with a 403 swap? I know ill have to do some any way and have somethings in mind but its stuff i can do, i cant however to a complete rear end swap......just not that good yet.

 

A good-running 350 will destroy the 7.5" axle in your 1980, never mind a 403. Of course, this is all a function of how you use the car. If you run street tires and don't race it with slicks, the axle will likely last a while.

As for swapping the whole axle, this is actually a pretty easy thing to do. The problem is that the only bolt-in axle for your car that's strong enough is the 8.5" axle found in the 84 H/O and 85-87 442 and GN cars.