Exhaust Manifold Heat Riser

[Michael Ketterer]

hello board, I have a dumb question on a.... stock exhaust heat riser 2 1/5 on big block stock exhaust manifolds?
((is the counter weight on the riser to the front of car or rear))
Thanks
Michael

[Stephen L.]

Re: Exhaust Manifold Heat Riser. FRONT *NM*

[Michael Ketterer]

Re: Exhaust Manifold Heat Riser. FRONT

Steve, Thanks Michael

[Tom D.]

Same answer for 250 HP small blocks in '63? *NM*

[Stephen L.]

Re: Same answer for 250 HP small blocks in '63?

I don't know. Check your AIM for the correct orientation

[Tom D.]

Thanks Steve - Will do. *NM*

[John H.]

Re: Thanks Steve - Will do.

Also note that the top side that goes against the manifold (with a flat "fire-ring" gasket) is flat, and the bottom side that mates with the "donut" on the exhaust pipe is chamfered to match the donut; if installed upside-down (which is easy to do), the donut will be destroyed and you'll have a major exhaust leak.

[Tom D.]

John - Remember your old post about plugs?

John - Thanks. The top is on top, but:

I wonder if any performance difference would result from "turning" the heat riser to a different orientation. (Other than for judging, I mean.)

Assuming the exhaust "air" if flowing in a uniform manner, the pressure on the valve plate should be the same across the whole surface...?

Also, do you remember ths size of those plugs you used to stick in the manifold, under the carb?

Thanks again.
Tom D.
4889

[John H.]

Re: John - Remember your old post about plugs?

Tom -

Radial orientation of the heat riser won't make any functional difference - just make sure the weight isn't anywhere near the positive battery cable connection to the starter solenoid at full travel. The cup plugs for the 3872783 cast iron intake "hot-slot" are 7/16".

[Tom D.]

Thanks John! *NM*