I recently posted that I was getting a 1997 350. well turns out its a 1991 tbi 350 from a full size Blazer. Im not sure what to do. I have my LT! T56 to put with this engine and a 4.11 posi rear to install at the same time. I have a little bit of money set aside for this. I am hoping to get suggestions as far as keeping my TPI or going carb. Also I'd like to do a cam swap while the engines out. Not sure whats the best route to go with this setup. Am looking for good streetable power.

 

Once the TBI is gone the engine doesn't remember what intake it had on top Fit your TPI stuff

get a 350 TPI memcal (tune ) and knock sensor to put into your existing ECM

Read link regarding head differences
https://www.thirdgen.org/forums/engi...-manifold.html

 

The real issue is what heads to use. The 350 TBI heads are probably okay for a stock TPI setup, but if you upgrade the TPI or go carb, they will become the limiting factor pretty quickly.

A simple solution would be to put your '85 305 heads on the 350. It should have dished pistons, so static compression shouldn't be too high. Your '85 TPI cam & lifters would be an upgrade from the truck cam as well (assuming they are in good condition).

Since you thought you were getting a '97 engine, you apparently thought you were getting Vortec heads. If you go carb and a cam upgrade, this kit would be a good value to get the good street performance you're looking for: https://sdparts.com/details/scoggin-...nter/sd8060aag

They used to offer the upgraded heads/gaskets/bolts/rockers without intake, but I don't see it on their site now. You could call and ask if they would still do that for you. With a Holley Vortec Stealth Ram intake, that would make a good performing package with a nice cam upgrade.

Speaking of cam, you might want to try to go with a roller cam, if the 350 is machined/drilled/tapped for it. The truck block casting has the provisions for it, but they weren't always finished machined, since the trucks got flat tappet cams.