305 vs 350

[Stephen7891]

I am going to rebuild by 1991 gmc c1500 this fall, i am doing a off body rebuild. I am not going overboard with the project as it is my first major build. I am replacing any worn parts and a few small upgrades fresh paint. My biggest issue is that if I have it striped down to the frame is it worth swapping the engine and installing a 350. Im not looking to make a lot of power but what kind of difference am I looking at for cost to power ratio doing this swap what would be the difference in power with the same upgrade but with each engine. Will the 350 bolt to the trans like the 305 or will I have to get a new trans, will there be a big issue with wiring, and are there any other issues that arise with switching the motor. I hesitate because the 305 works so well and i have never had an issue with it it has 240000 kms on it now. Also is there a difference between a gmc 350 and a chevy 350 from the same model.

thanks in advance

 

[Tavi]

Chevy and GMC motor are the same thing.

350 will bolt right in place of a 305. The difference in power will not be out of this world, but noticeable. The wiring should be all the same. Different throttle body. And different computer tune. But all plugs should fit.

 

[Ed_P]

If you start to budget money towards the engine just find an old 350 and do it and have it ready for the build time. The general thought is why spend the same money on a 305 then a 350. If it's heavy use you may get some MPG's out of the 305 ? Find an engine guy, he may like those 305's and swap you out, some of those guys use them for boat applications and they tend to be somewhat in demand.. ? which is what I did..