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On my last Astro I had the same engine but vortec heads did not come out till 96 so although they are center bolt heads they should not be vortec unless someone swapped them on. I bought a 305 from an 86 Camaro it had TPI fuel system on it and I sold that. I installed 305 vortec heads and a cheap china made 4 barrel intake manifold and used a 4 barrel to TBI adapter. Engine ran great but the intake leaked coolant into the cylinders and eventually destroyed the engine. Dont buy a cheap after market china made intake like I did. By te way on a vortec headed engine the intake only has 8 bolts to hold it on if your intake has more then 8 it is not a vortec. Mark
 

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Discussion Starter · #42 ·
Thanks for the link Prairiedog. It is interesting.

After a couple months of looking for a decent 5.7 and not finding one this one kind of fell into my lap. It was super cheap and delivered.

It's not an LS, it's a Vortec but it still has the same characteristics as a normal SBC except for the intake manifold. My pan and mounts bolt up exactly the same. It doesn't matter that its a gen ii because its getting a tbi manifold and will run fine with my gen i ecm and corresponding sensors.
 

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Discussion Starter · #43 ·
It looks like I have to buy a "cheap" manifold. I can't justify spending twice what I paid for the engine on an Edlebrock.

I've reduced it down to two choices. Ebay, from what seems like a reputable company and for a few dollars more there's Jegs. There doesn't seem to be a big difference.
 

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Discussion Starter · #44 ·
I went with the ebay manifold. They have sold a bunch of them and almost all good reviews. What I learned is that they tend to blow out stock gaskets. After a lot of research I ordered the Fel Pro MS-98000-T set that also comes with valve cover gaskets. They are steel reinforced which solves the blow out problem.

For the oil pan I got the one piece Fel Pro OS-34500-R and for the exhaust manifolds Fel Pro MS-94054. All of these are the same for both the 5.0 and 5.7.

I still have a few things to get but its coming along.

I also finally got the engine off the cart and on to the stand. I had to search around for the hardware to my cherry picker. It somehow got put in with my transmission parts.
 

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If you're plan is to run headers I would strongly recommend using "Percy's Dead Soft Aluminum Gaskets"
I had to replace mine after a couple years and that is a job I would wish on no one...
I put in the aluminum, tightened them once and have had no issue since. 2 yr so far.
 

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Discussion Starter · #46 ·
I'm not running headers. With it being AWD there's no room for the Hedman shortys that everyone runs on the 2wd.

That's something to keep in mind if we decide to do the Blazer though. Thanks.
 

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Discussion Starter · #47 ·
Not a lot of progress at the moment but I did get the accessories off and pulled the water pump.

Of course it's caked with orange crud. Since I'm putting a new water pump in anyway that's no big deal but I still need to clean out the block. My plan is to put the old w/p back on, plug the outlet and dump about a gallon of vinegar into the water neck and let it sit a couple days. Once it's in and running I'll do a complete flush on it and go green as God intended. :D

Its looking like the guy who said he has the remaining parts I need is blowing me off so a trip to PnP is probably in my near future. I still need a TBI unit, a driver side exhaust manifold and if I get lucky a 94 BJLH 5.7 PROM chip. After that it's mostly bolts and other hardware until I get the old engine out and see what else may need to be replaced.

(Note to any Admin) Is there a way to retitle this thread to "94 AWD 5.0 Vortec TBI project"?
 

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If it matters to ya Bikley you can change your post title yourself. ^^^^^
otherwise PM one of the mods to grab their attention.

Sucks about your parts guy.
When you find the TBI be sure it came from a van otherwise you may run into difficulties w/ the throttle cable linkage. My '93 uses a cam pulley type of deal where the TBI from a pickup or car uses a different linkage. I'm certain you can find a workaround but for me it was easier to get the right one.
 

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Discussion Starter · #50 ·
Thanks Wood. Mine is the CPI vin W so I figured on changing the throttle cable anyway, so that's something I will definitely look for.
 

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Anytime, just a tidbit of info that might save you grief. I tried a holley 2" bore and the linkage was wrong. I cut the linkage off and welded the stock cam to the shaft on the holley which worked a charm.
https://www.astrosafari.com/viewtopic.php?f=42&t=107490

A year or two after I was chasing issues and wanted to go back stock to eliminate that from the possibilities and got lucky to find the van TBI in a boneyard only 10 miles from me.
 

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Those manifolds look like they are for the Vortec heads not the TBi
 

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you do not want a chip for a 5.7 if your running a 5.0 it will not run right, same with the injectors , the 350 injectors will be to much for a stock 305. pretty much everything else is the same. I had a cammed 305 with hedmans hedders and dual exhaust and the 350 injectors were causing surging so I tried a 350 chip and it would not run. So I went back to 305 injectors and had a chip burned and all was fine.
 

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Discussion Starter · #55 ·
Ok some stuff I learned about throttle bodies. Physically the small block ones are all the same with the difference being the flow rate of the injectors.

4.3 40 lb/h @ 9-13 psi
5.0 45 lb/h @ 9-13 psi
5.7 55 lb/h @ 9-13 psi
5.7 hd 65 lb/h @ 9-13 psi

The trick now is just find a 305 unit and I should be good to go.
 

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Discussion Starter · #56 ·
The next issue is the plastic timing cover. Can I just change the gasket and reuse it or do I need to replace it? It's a roller cam so do I need to replace the cam button if I get a metal cover?
 

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Discussion Starter · #57 ·
The timing cover decision is made. I just got the stock style plastic one without the crank sensor hole.

I got a new water pump too so I'm down to the TBI unit and hardware.
 

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^ good, because the plastic timing covers are not reusable.
 

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Discussion Starter · #59 ·
Yeah, this has already turned into more of an ordeal than I planned on. I didn't want to mess around with a cheap metal cover and risk warping it putting in the crank seal. Plus having to drill and tap a couple holes and press in the guide pins, so it was an easy decision.
 
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