How to Put a Vortec Motor in a TBI Truck

[Schurkey]

Has the Vortec head on the right bank been drilled to allow coolant flow thru the bypass system?


The coolant hole in the manifold is an extra. If you don't have something to put in that hole, plug it. I prefer brass plugs, but aluminum works ok. Steel plugs tend to seize in the manifold.

 

[GoToGuy]

My 98 tahoe is supposed to have a little under 300 hp. Aftermarket vortec style heads for prevortec V8's are available. So vortec perfomance but TBI fit. No fabrication or adapting. My in the box 383 has an Edelbrock vortec TBI intake manifold. Fabrication and home adapting has it's place , but GM allready did it for you. At some place you might reach the point of diminishing returns. I will never deny what someone takes on, more power to you. I just see GM made a lot puzzle pieces that i can mix and match make something better. They made at least 4 external oil coolers. I've seen 6 different external trans fluid coolers. So yeah i see your idea for improvising and improving.

 

[Erik the Awful]

My engine is a TBI block with vortec heads. As I can decifer, the TBI water pump will work as the bypass port will flow. What is the port just driver side of the thermostat housing?

@Shawnstockham
I'm not sure, but if you don't have anything screwed into it, plug it.

If you don't have the bypass passage drilled in your passenger side head, you will need to run the Vortec water pump. You're running the same block and head combination as I am. I had some weird overheating issues until I swapped the Vortec water pump on and ran the external bypass hoses. Now I run a rock-solid 185-188 degrees.

Next time I have the heads off (hopefully never) I'll drill that passage in both heads, in case they ever swap positions. Then I'll also switch back to the correct TBI water pump.

 

[Erik the Awful]

@kennythewelder @df2x4
Can I get this thread stickied? People are being referred to it fairly often.

 

[kennythewelder]

@kennythewelder @df2x4
Can I get this thread stickied? People are being referred to it fairly often.

Good write up, done, it's a sticky.

 

[cheapevil]

So I picked up a complete Vortec motor with 110K on it, out of a 98 Tahoe from my landlord.
My thought is after reading through this thread, is that the best way to go about swapping it
into my 95 K1500 TBI. Is to go with the Chevrolet Performance Vortec Intake Manifold with TBI
and leaving all other bolt on parts(ie water pump etc) Vortec motor correct. Am I on the right
path here? Thanks for the feedback.

​

 

[Schurkey]

My thought is after reading through this thread, is that the best way to go about swapping it
into my 95 K1500 TBI. Is to go with the Chevrolet Performance Vortec Intake Manifold with TBI
and leaving all other bolt on parts(ie water pump etc) Vortec motor correct. Am I on the right
path here? Thanks for the feedback.

You'll need the Vortec exhaust manifold, and the convoluted/insulated metal tube and fittings from exhaust manifold to intake manifold, to keep the EGR functional. That manifold may/may not have a threaded boss for the O2 sensor...but maybe your sensor goes in the pipe, not in the manifold. Dorman used to make an exhaust manifold that was "double-tapped" for both the EGR plumbing and the O2 sensor. I wasn't able to find it last time I looked.

The crank position sensor will not be used.

I don't know if the A/C compressor and alternator are in the same places as the TBI. Never paid attention. Wouldn't surprise me if you needed some rework to the wire harness or A/C hose routing to make it fit.

That intake manifold is double-top-secret expensive. Over $500.

 

[cheapevil]

You'll need the Vortec exhaust manifold, and the convoluted/insulated metal tube and fittings from exhaust manifold to intake manifold, to keep the EGR functional. That manifold may/may not have a threaded boss for the O2 sensor...but maybe your sensor goes in the pipe, not in the manifold. Dorman used to make an exhaust manifold that was "double-tapped" for both the EGR plumbing and the O2 sensor. I wasn't able to find it last time I looked.

The crank position sensor will not be used.

I don't know if the A/C compressor and alternator are in the same places as the TBI. Never paid attention. Wouldn't surprise me if you needed some rework to the wire harness or A/C hose routing to make it fit.

That intake manifold is double-top-secret expensive. Over $500.

Thanks for the info. The exhaust manifold is there, and that convoluted metal tube might be there too. It's been about month or two since I really looked at it. Yes that intake is spendy but I got a sweet deal on the motor so it is balancing out. Ordering intake tomorrow, payday. It looks like I'll need a new distributor too, is that correct? Thanks again for the feedback. Any other helpful tips or tricks to help me, pull this motor swap off, will be greatly appreciated.

 

[Schurkey]

It looks like I'll need a new distributor too, is that correct?

Only if the existing TBI distributor is no longer serviceable. They do have problems with the magnet near the pickup coil cracking. The pickup coil itself, the gear at the bottom, and the module are readily replaceable. Better to have a "good used" Delco distributor than a brand-new Communist Chinese knockoff.

 

[Erik the Awful]

Buy a square-bore carburetor Vortec intake, a square-bore to spread-bore adapter, and a flat-plate TBI adapter and you'll be in at half the price of that GM intake while also being ahead of the game if you ever decide to put a square-bore style injection system on it.