305 tbi swap to crate 350 short block

[87Hi-v15HND]

Was going to do an LS swap and changed my mind!

My 87 GMC’s stock 305 crapped out and I want to put a 350 in. Looking for a little more power with a mild cam. Any suggestions on a good motor and where to buy from?

Also with a new 350 and the Vortec heads will I need a new tbi? Or will my old tbi fit and function properly?

What (electrical/mechanical) modifications will I have to make for this swap? I am some what trying to make this a budget build but at the same time I want this truck to be a daily reliable driver if need be so I’m willing to put money into it if need be.

I am also running the 700r4 tranny if that makes any difference.

Thanks guys looking forward to your inputs!

 

[Frankenchevy]

I don't believe stock tbi will fit vortec heads directly. I have a complete vortec intake / throttle body I would sell you cheap, but it won't do you any good without the right ecu. there are members on here that could get you set up ecu/harness wise, though.

I think your setup will work with any pre-96 headed long block. not sure about the 305 vs 350 tbi differences though, as the head is different from 305 to 350. ports might need to be matched up.

good luck

 

[4WDKC]

You will either need a tbi intake manifold for a vortect heads $$$ or a carb intake for vortec heads with an adapter, either way you will need a tune, new fuel pumps stock ones cant supply the pressure for vortec flow numbers,make the pressure regulator adjustable, then you will run into the stock throttle cable bracket has to be modified to bolt to the engine. After doin so you will need to check that you can get full throttle from the pedal, if not you need to mod the bracket to correct whatever is preventing it from happening. Just went through the things on mine with swapping in a cam and vortec heads. It broke a valve spring in less that 500 miles on new springs may have damaged the engine (havent had a chance to check) if there is any damage I think its getting a 5.3/4l60e.