TBI 350 to Vortec and Roller Cam

[Daveo91Burb]

I have two complete 350s sitting in my shop: 1) 1990 TBI 4-bolt from a 3/4 ton burb with about 100K on the clock 2) a 1996 vortec 2-bolt (assuming) from a 1/2 ton burb with about 220K. My plans are to use the 4-bolt block and the vortec heads but keep the TBI system. I already have the GMPP 4 barrel manifold and an adapter to mount the TBI.

1. What are my chances of getting by with just a cylinder hone and new rings/bearings, etc. on the 4-bolt? If I can't I'll do full machine work with .030 overbore, etc. If I go this route, I might even go all the way and stroke it to a 383.

2. I'll get the vortecs reworked by a cylinder head shop. Nothing fancy, just stock. I got the heads off tonight and turned them over, didn't see any cracks around the valve seats. I plan to reuse the vortec rocker arms, pushrods, lifters, spider plate, dog bone retainers to convert to roller cam. The 4-bolt has the tapped holes for the spider plate. (It fits). Any problems here? Anything I should not reuse? Didn't see any bad wear on anything...

3. Thinking about even reusing the stock vortec cam. (Again, not looking for crazy here, just better power and economy than stock TBI) Should I get it re-ground? I know there's a place in my area that will do it.

4. I know there will be work to do with the TBI system and I'll have to decide on what to do with EGR. I have some questions here, too, but I'll save those for now. ( There is a tuner in my town that I will be using for computer stuff)

5. One more question that I think I know the answer to: can I use the Vortec distributor in place of the TBI one? I know that with the roller cam I'll have to make sure I have a mellonized gear on whichever one I use.

Thanks, sorry for all the questions. Lot of stuff swimming around in my brain right now....

 

[dougbert]

#1 The best bet is to either mic the cylinders yourself or ask the machine shop to see within specs. at 100k most of its life is gone, but if it was treated well, might still have 50k left in it. You need real numbers from the block itself then you know what your options are

If within specs, then new cam bearings, main bearings and rod bearings, along with new rings. A light hone as well.

#2 the vortecs should help out a lot. TBI heads are poor, poor, poor. Check the lifters

dougbert

 

[oneluckypops]

vortec distributors are PLASTIC, and the crab cap is a real PAIN IN THE ASS!!!

 

[Daveo91Burb]

Thanks, guys.

I'll get the TBI heads off and MIC the bores, but I think I'm just leaning toward getting the block machined now. And I'll just stick with TBI Dist - probably replace the pickup and whatever else I can.

Any thoughts on reusing the roller cam and other valvetrain parts from the vortec motor? Pushrods seem straight and no noticeable wear on the cam and rocker arms.