Blocking heat crossover on a 440

Posted By: 440mopar

Blocking heat crossover on a 440 - 09/11/14 04:47 AM

I am in the process of having my stock 440 six pack motor rebuilt. The cast iron intake manifold is quite discolored where the heat crossover passage is. I would like to know if it would be O.K. to block the crossover off so that after I repaint the intake it won't discolor.

Posted By: MR_P_BODY

Re: Blocking heat crossover on a 440 - 09/11/14 04:56 AM

If you dont run a carb that uses the heat for the choke
then its no problem... put a piece of metal in it
so the gasket seals it(some thinner SS)
EDIT
When I did it years ago I used high temp rtv on the head
side to seal it then the gasket to hold it in place..
worked fine

Posted By: 440mopar

Re: Blocking heat crossover on a 440 - 09/11/14 05:01 AM

It has the factory choke on it but I typically don't drive the car during the cold weather months. Does anyone sell a valley pan designed for blocking off the crossover?

Posted By: wingman

Re: Blocking heat crossover on a 440 - 09/11/14 05:05 AM

If your engine is truly "stock" and you block it the choke won't work any more.

If you run a carb with an electric choke, or feel you don't need a choke at all, then by all means, block away.

The best way IMO is to just use one of the valley pans with the holes already blocked. Mr Gasket, MP, and others sell them both ways--open and blocked. Other guys have used little pieces of tin or whatever to block them, but be careful. Too thick and they can push your manifold up an cause a vacuum/oil leak. To thin and they can burn through.

Posted By: MR_P_BODY

Re: Blocking heat crossover on a 440 - 09/11/14 05:19 AM

Quote:

It has the factory choke on it but I typically don't drive the car during the cold weather months. Does anyone sell a valley pan designed for blocking off the crossover?

Yes they do now days... most of the companies do

Posted By: gregsdart

Re: Blocking heat crossover on a 440 - 09/11/14 01:08 PM

A small thin (.015?) piece of stainless will do the job as well. Years ago I bought intake gaskets that came with a piece made to put between the gasket and head, worked just fine.

Posted By: Mr.Yuck

Re: Blocking heat crossover on a 440 - 09/11/14 01:11 PM

you can also use a piece of you old intake to block off the wells. The pan gaskets w/ the block-offs are more expensive. FWIW chokes are over rated. It's not like you are going to be driving the car in 30* weather.

Posted By: GomangoCuda

Re: Blocking heat crossover on a 440 - 09/11/14 03:38 PM

http://www.summitracing.com/parts/fel-1215/overview/

Not that expensive considering that unless it is cracked it can usually be reused. Do not use the paper gaskets that come with it. They are too thick. Mopar didn't use paper and neither do I unless it just doesn't fit good enough to seal. If you must use the paper buy the thinner .015 thick gaskets from a couple of other sources.

I think someone here did an electric choke conversion on a sixpack some years ago. I don't remember how it turned out or who did it. There isn't anything that just bolts on.

Posted By: GomangoCuda

Re: Blocking heat crossover on a 440 - 09/11/14 03:45 PM

Quote:

FWIW chokes are over rated. It's not like you are going to be driving the car in 30* weather.

Maybe not in Maryland but in Michigan 30 degrees is called Spring.

Posted By: Mr.Yuck

Re: Blocking heat crossover on a 440 - 09/11/14 04:08 PM

Quote:

Quote:

FWIW chokes are over rated. It's not like you are going to be driving the car in 30* weather.

Maybe not in Maryland but in Michigan 30 degrees is called Spring.

ha! Used an old fashion pull choke. I have one on this car. In any event a six pack that's been sitting will require ample cranking to get fired.... I pull the choke about 3/4 fire it and opn it full w/in about 5 seconds... (in colder weather)

Posted By: an8sec70cuda

Re: Blocking heat crossover on a 440 - 09/11/14 05:18 PM

Get the valley pan that already has the crossover holes blocked.

Posted By: okie

Re: Blocking heat crossover on a 440 - 09/11/14 09:44 PM

I got my gasket from Jeg's with free shipping

Posted By: Chris2581

Re: Blocking heat crossover on a 440 - 09/12/14 12:57 AM

Fel Pro #1215 is what you seek.