How to Put a Vortec Motor in a TBI Truck

[L31MaxExpress]

The throttle cable bracket is an easy problem to overcome. Edelbrock has made one for years that is correct for the application and it is adjustable for both height and distance.

You must be registered for see images attach

 

[Erik the Awful]

...but apparently it's made of gold. $70

Edelbrock 8031 Edelbrock Throttle Cable Brackets | Summit Racing

Free Shipping - Edelbrock Throttle Cable Brackets with qualifying orders of $109. Shop Throttle Cable Brackets at Summit Racing.

www.summitracing.com

 

[L31MaxExpress]

...but apparently it's made of gold. $70

Edelbrock 8031 Edelbrock Throttle Cable Brackets | Summit Racing

Free Shipping - Edelbrock Throttle Cable Brackets with qualifying orders of $109. Shop Throttle Cable Brackets at Summit Racing.

www.summitracing.com

Jeez, those were like $30 when I bought that one.

 

[Majoraslayer]

Time to necro a pinned post. If one were to drill the Vortec heads for the coolant bypass, how exactly would you do it? I'd imagine you could take a head gasket to mark the correct spot to drill, but is there a certain angle you have to drill it? Do you just drill until you feel it reach an opening on the other side, indicating you've drilled all the way through into the passage the coolant will go through? Or is there a specific depth you need to carefully account for?

 

[Schurkey]

Far as I know, you just drill 'til you "hit water". Of course the casting won't have any water in it when it's being drilled. Drill straight "down" until you break through to the water jacket.

 

[Majoraslayer]

Assuming you run a TBI block with the bypass holes drilled out in the Vortec heads (probably irrelevant, but including it), what intake gasket set should be used? There seems to be a lot of debate on the importance of running TBI intake gaskets, something to do with the way the coolant flows for the OEM TBI intake's plenum. OP mentioned running regular gaskets and letting coolant flow where it wants, but I want to revist that point. I'm hoping to get my hands on a good used GMPP Vortec TBI intake, but if that deal falls through I'll probably go the carb/adapter route. I'm not sure how the importance of that TBI blockoff translates when using other intakes. Since the Vortec heads have such a different intake lip height, would TBI gaskets even work on Vortec heads?

 

[Schurkey]

If the Vortec-TBI intake manifold doesn't have a hot-coolant passage from under the thermostat housing to the right-rear corner, (warming the plenum) then having the gasket blocked-off back there isn't needed.

The whole point of having the gasket blocked-off is to promote coolant flow through that under-plenum coolant passage via the heater circuit.

 

[L31MaxExpress]

If the Vortec-TBI intake manifold doesn't have a hot-coolant passage from under the thermostat housing to the right-rear corner, (warming the plenum) then having the gasket blocked-off back there isn't needed.

The whole point of having the gasket blocked-off is to promote coolant flow through that under-plenum coolant passage via the heater circuit.

Here in Texas, I always put standard open, carb style gaskets on them. I always felt in our weather atleast, opening the rear passageways promoted circulation from the rear to the thermostat, similar to the AN lines guys add to race engines. I have even seen them installed backways, closed ports under the front water crossover ports. Interestingly that engine with them backwards did not even run hot.

 

[Schurkey]

I have even seen them installed backways, closed ports under the front water crossover ports. Interestingly that engine with them backwards did not even run hot.

With the front coolant ports nearly blocked-off (except for the lil' steam-hole in the gasket) the two temp sensors might not be reading the true coolant temp. Hard to know without doing some testing. The gauge sending unit in the left head might run hot--or not, but the computer sensor in the manifold would likely run cool since it's getting very little flow in the coolant crossover passage of the intake manifold.

 

[L31MaxExpress]

With the front coolant ports nearly blocked-off (except for the lil' steam-hole in the gasket) the two temp sensors might not be reading the true coolant temp. Hard to know without doing some testing. The gauge sending unit in the left head might run hot--or not, but the computer sensor in the manifold would likely run cool since it's getting very little flow in the coolant crossover passage of the intake manifold.

The passageway that runs under the manifold is easily as large as the thermostat opening.