96-99 5.7 vortec swap

[cfan10]

Does anyone know what a 5.7 vortech swap consists of in a 90 suburban 5.7 TBI? Is it a direct bolt up? Trying to find a cheaper solution to 5.3 vortech. Thinking the trans will line up? Thanks in advance.

90 suburban 350 tbi

[Slammed84]

Direct bolt up yes, direct wire up..... no way

[kevinr1970]

I don't know (never done it) but I do know there is a vortec-to-TBI manifold available from GMPP.
I would *think* that once the manifold is in place, it is a bolt in/wire up deal?

[kevinr1970]

Manifold

But... there is this note:
"This manifold is primarily intended for use with Vortec heads on pre-1996 engine blocks. Blocks manufactured in 1995 or earlier have thermostat bypass passage from the block directly to the water pump. If manifold is used on 1996 and later engines (which do not have the bypass in the block), you must run a coolant bypass line from the manifold to the 5/8" hose nipple on the water pump (passenger’s side). Suggested routing is from the 3/8 NPSF boss on manifold to the water pump."
"These Vortec manifolds with TBI from Chevrolet Performance are designed for maximum horsepower with throttle body fuel injection and EGR usage. These manifolds will fit all Vortec-designed cylinder heads."

Might be cheaper to find a vortec 4bl manifold and use a TBI adapter?
1-11/16” bore TBI adapter
2" adapter
2-1/8" adapter

[Slammed84]

Originally Posted by kevinr1970

I don't know (never done it) but I do know there is a.vortec-to-TBI manifold available from GMPP.
I would *think* that once the manifold is in place, it is a bolt in/wire up deal?

I think he is talking about swapping the entire engine. If not, then I want the Vortec heads hes not using.....

Im sure it can be done, but there are electrical issues you will run into. One i know of for sure is the vortec motors use 4 oxygen sensors, TBI is only 2.

Also the fuel lines are different so you would want to find a donor Burban for those.

I also suggest, if you go through with it, to go ahead and make the fuel spider upgrade while the vortec motor is out.

[kevinr1970]

For some reason I read it that he wanted a vortec "long-block" and to keep the TBI; after rereading the OP, not sure where I got that

So yes completely different wiring, fuel delivery, etc.
The only thing I think you would save going vortec 5.7 vs. 5.3, is engine mounts, and manifolds/headers and exhaust mod.
I have seen people asking silly $ for a high-mile 5.7, and I have seen some pretty cheap LS engines, that part might be a wash.

[y5mgisi]

Definitely go 5.3 over the 5.7. you will be in it the same amount of effort and money.

[cfan10]

Yeah I'm interested in changing the current 350tbi to 98 350 vortec engine, thought it'd be cheaper to do instead of a 2000+ 5.3 vortec swap. How hard is it to wire up versus a newer vortec? Thanks.