What to block heat riser passages with...

[The Dartman]

Does anyone know of a product besides Hard Blok for blocking the heat riser passages in a set of BB heads? My local speed shop recommended using a mixture of what they called "furnace cement", but know one seems to know exactly where I can get some. Hard Blok is very expensive and comes in a gallon size that is way too much for just doing the heads.

Any ideas?

Dartman

[SpeedSleaze]

You can buy the Fel Pro Performance valley pan with the heat risers blocked. FPP 1214, $19.98 from that online HP parts place that runs a GM product in NHRA.

Mr Gasket also sells gaskets that would go on top of the valley pan and they include little block off plates. The gaskets are thick and could mess up the manifold alignment. I have the Fel Pro piece.

[SpeedSleaze]

Check that! Not sure if you're looking for filler or just to block the heat risers.

Also, the 1214 is for low deck. 1215 for RB. And they have one for Max Wedge sized ports.

[The Dartman]

Thanks for the reply Mr. Sleaze.

The main purpose of filling the heat riser passage in the headswith cement/hard block is achieve better flow from the heat riser cylinders.

The car is 90% strip only and will have a non heat riser high rise single plane intake that should already block off the passage.

I have found only one site on the web that talks about using furnace cement to block this passage, so I was wondering if anyone else has done it.

Dartman

[SpeedSleaze]

Maybe a hi temp epoxy... Epoxy "sounds" lighter than cement.

[23T]

I blocked mine with aluminum. Melted the aluminum in a crucible and poured it in the heat riser hole through the exhaust port. Worked the to shape after cooling and put the valves back in

[The Dartman]

That's what my brother did to his Olds heads too. He melted an old piston down and worked it into the passage.

I wouldn't think that molten aluminum would be very easy to work with trying to form a cup shape under the valve, but I think I'll give it a try. Certainly much lighter than cement...

Thanks for the replies....
Dartman

[23T]

Originally posted by The Dartman
That's what my brother did to his Olds heads too. He melted an old piston down and worked it into the passage.

I wouldn't think that molten aluminum would be very easy to work with trying to form a cup shape under the valve, but I think I'll give it a try. Certainly much lighter than cement...

Thanks for the replies....
Dartman

After it cools just work it with a die grinder to the shape you want just be sure to pour enough material to start with

[Bryant Fields]

I think y'all are fixin' to over engineer this project. All you have to do is pack it full of aluminum foil.

[The Dartman]

I actually am going to try and weld a piece of coffee can in the heat riser passage.

[23T]

Tin to cast iron man if you can do that you can weld a snowcone to a screen door

[The Dartman]

"Actually" I was joking. I thought the post about aluminum foil was a joke, too.

I will melt aluminum and work it into the hole and finish it off with a die grinder.

Dartman

[23T]

Originally posted by The Dartman
"Actually" I was joking. I thought the post about aluminum foil was a joke, too.

I will melt aluminum and work it into the hole and finish it off with a die grinder.

Dartman

LMAO I was going to hire you to come be a pipe line welder and try and get the foil pokerer-iner come and back fill the ditches

[Bryant Fields]

HAHAHAH,...OOOoooooh K! uhmmm, I was serious!!
But then why go to all that trouble when if you are using an aftermarket single plane intake(just ASS-uming that you are) there is no exhaust gas reaching the intake runners anyway?

[SpeedSleaze]

The real goal/ purpose is to improve exhaust port flow and not so much keeping the the intake manifold from heating up. Though I've not read much on this being an issue.

[The Dartman]

Not only to improve flow in the heat riser cylinders, but also to make the flow as close to equal as the other cylinders.

Both my machine shop and my porter both agree this is a worthwhile update, since flow is improved in the heat riser passages. This will be a 95% race only head as well.

I think the intake block off would be sufficient if I wasn't going to do some serious porting along with 2.14 and 1.81 valves. As long as I'm going all out, I might as well do it as best as possible.

I hope I didn't offend with the foil comments.

Dartman

[Bryant Fields]

No problemo Senor! I thought you were doing it to keep the intake air cooler.