Blocking cylinder head exhaust crossover

[Doug Domm]

I’m asking for suggestions on what to use and tips on doing this? Thanks

[SSDiv6]

Originally Posted by Doug Domm

I’m asking for suggestions on what to use and tips on doing this? Thanks

Melt an aluminum bar or an old piston or use Cotronics Durabond Epoxy 7032 or Loctite 2000 degree putty.

http://www.cotronics.com/WEB%20SHEET...plate%20NP.pdf

https://www.grainger.com/product/2TK...P7A1P:20501231

[Jeff Stout]

Dont use lead. I made bvb that mistake. I made a stainless plate to cover crossover and put under gasket.

[Dwight Southerland]

Plaster of Paris.

[Doug Domm]

When pouring aluminum what prep to the head? Do you heat or warm the head? I’m thinking maybe heat them up in the barbecue before pouring and again after pouring to slowly bring the heat back down? Or am I overthinking this?

[Dean Feiock]

Zinc bar. Easy to melt and no shrinkage.

No cylinder head preheat needed.

Try Mondello Performance or McMaster-Carr industrial supply.

[SSDiv6]

Originally Posted by Doug Domm

When pouring aluminum what prep to the head? Do you heat or warm the head? I’m thinking maybe heat them up in the barbecue before pouring and again after pouring to slowly bring the heat back down? Or am I overthinking this?

[Mark Yacavone]

I don't recommend doing it like the video shows on a Stocker..God knows, you wouldn't want to make grinding marks in the port area ..You'd have to hide them.

I've done maybe a 100 sets for engine builders around here.
I make little metal tabs that are the shape of the passage opening down in the port. I leave a little tail on the tab that I bend and prop up against a 5/16 bolt in the guide. Alternatively, you can used cotton balls, soaked with P of P . stuffed down in the port.
I fill from the level port side. If you pour too much, just knock it down with a grinder, and mill the rest when you skim the intake side.
I don't pre-heat anything. .If there's a leak ,it'll fill up with carbon before long.. It's not that critical.
As long as you don't blend the plug into the bowl, it's legal. Leaving it back a tad doesn't hurt anything.
I just use old pistons or aluminum scrap
I haven't tried the zinc, but i might. It might take less heating gas. The price of oxy/acety keeps going up like crazy

[SSDiv6]

Originally Posted by Mark Yacavone

I don't recommend doing it like the video shows on a Stocker..God knows, you wouldn't want to make grinding marks in the port area ..You'd have to hide them.

I've done maybe a 100 sets for engine builders around here.
I make little metal tabs that are the shape of the passage opening down in the port. I leave a little tail on the tab that I bend and prop up against a 5/16 bolt in the guide. Alternatively, you can used cotton balls, soaked with P of P . stuffed down in the port.
I fill from the level port side. If you pour too much, just knock it down with a grinder, and mill the rest when you skim the intake side.
I don't pre-heat anything. .If there's a leak ,it'll fill up with carbon before long.. It's not that critical.
As long as you don't blend the plug into the bowl, it's legal. Leaving it back a tad doesn't hurt anything.
I just use old pistons or aluminum scrap
I haven't tried the zinc, but i might. It might take less heating gas. The price of oxy/acety keeps going up like crazy

Mark,

The video was just an example and I should have put a note clarifying the issue for a Stock Eliminator engine. You can still do it the way shown for a Super Stock cylinder head.
I do not do it this way either, I stuff aluminum foil down the exhaust crossover passage and pour the molten aluminum down the intake face of the cylinder head.

[SSDiv6]

Originally Posted by Mark Yacavone

I haven't tried the zinc, but i might. It might take less heating gas. The price of oxy/acety keeps going up like crazy

Mark,

Zinc melts at a lower temperature than aluminum at around 787°F versus 1220°F for aluminum.