Ancient Heads

[CTX-SLPR]

Yeah, I'm talking the '78 short port heads. Is there anything preventing me from using a dead '78 3.8 as a mockup motor in my Riviera when it comes to intake and exhaust plumbing? Ie, will a Champion intake physcially bolt and sit correctly on the short port heads?

Thanks,

 

[Brad Zeidler]

the exhaust manifolds will bolt on just remember the port sits 3/8" lower and the intake should also bolt on for mockup purposes. The bolt holes are in the same location,but not the ports.

 

[CTX-SLPR]

Ok, if the exhauste manifolds are in a different spot I'll just swap for the spare set of heads 8445 heads I have sitting around anyway, I'm trying to make as little work for myself as possible in capitalizing on my resources from the '78 Regal and the '64 Riviera to make it all come together smoother. A mockup motor will allow me to computer tune the motor in the Regal while mocking the turbo and other plumbing up in the Riv at the same time.

 

[shaggy]

the exhaust manifolds will bolt on just remember the port sits 3/8" lower and the intake should also bolt on for mockup purposes. The bolt holes are in the same location,but not the ports.

Isn't the exhaust flange angle different? I believe the top of the exhaust port is closer to the engine center line, and the port is higher up on the head. I wish I had a better picture of it. A 79-up intake should bolt up, but the intake ports will overhang the head ports.

Left is 78 head and the right is an 8445.

 

[CTX-SLPR]

Uh oh.... are the exhaust manifolds the same casting?

 

[shaggy]

Nope... The port shape is different.

 

[CTX-SLPR]

Well looks like I have another item I'm going to have to replace then.