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Discussion Starter · #1 ·
Darrow has his 74 BB pretty well set now. Carb, ignition, etc. He also changed the intake manifold gaskets, and now it has a slight vacuum leak. So, he waants to know, which is the best intake gasket set for the 74 BB 454.Also, who makes plates to close off the exhaust crossover? Part#'s?
He is going to redo it again, but as with all of us, would like it to be the last time.:laughing:
 

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Bird, years ago, and I still have one like that....we used to use Plaster OF Paris to block off the heat riser passages...keeping carb much cooler....

I never had any warmup problems from it either, this in Maryland....go figger....I did the same trick on an intake here for that SBC boat of some months ago....but it's not run yet....

:thumbsup:
 

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bird just now got home lots of traffic ave 25 from mv to san clemente temp stayed at 195 all the way. outside must be around 100 or more next time I will take that ice tea to as soon as I get a cup holder and the a/c fixed next week or next month I hope.
 

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Bird, years ago, and I still have one like that....we used to use Plaster OF Paris to block off the heat riser passages...keeping carb much cooler....

I never had any warmup problems from it either, this in Maryland....go figger....I did the same trick on an intake here for that SBC boat of some months ago....but it's not run yet....

:thumbsup:
Does that PoP really work well? I've thought about using some type of filler instead of those flimsy plates...
:cheers:
 

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Does that PoP really work well? I've thought about using some type of filler instead of those flimsy plates...
:cheers:
Well, it was used on several Ponchos over the decades, never a problem....years later pulling the intake and finding it totally intact, just a bit scoarched on the gasket plane, maybe a pucker hole in it,...but still solid and not passing gas.....

please no comments about that 'gas attack'.....


:rolling: :cheers:

The carb of course ran about 50000F degrees cooler...could actually touch it then....

this boat has a electric choke, round, on side of an AFB....so no need for that heat riser to do jack.....
 

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BG hasn't come out with a choke for the King Demon yet, anyway. :laughing:

Back to the gasket thing, I like Fel-Pro gaskets for most any application, but do use RTV for the ends of the valley in lieu of those aggravating little strips everyone makes...
 

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most hardware stores sell thin galvanized steel sheet you can carefully cut a block plate from for the intake gasket to block the exhaust heat flow, but in colder areas this may not be the best idea. many intakes designed for racing don,t have the exhaust transfer provision.

this might be of interest

http://victorylibrary.com/mopar/intake-tech-c.htm

as for gaskets, the thicker FEL-PROS TEND TO WORK REALLY WELL IN MOST ASSEMBLYS

http://www.jegs.com/webapp/wcs/stores/servlet/product_10001_10002_65890_-1
 

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most hardware stores sell thin galvanized steel sheet you can carefully cut a block plate from for the intake gasket to block the exhaust heat flow, but in colder areas this may not be the best idea. many intakes designed for racing don,t have the exhaust transfer provision.

this might be of interest

http://victorylibrary.com/mopar/intake-tech-c.htm

as for gaskets, the thicker FEL-PROS TEND TO WORK REALLY WELL IN MOST ASSEMBLYS

http://www.jegs.com/webapp/wcs/stores/servlet/product_10001_10002_65890_-1

I have NEVER found any longevity to using blocking gaskets, sheets of metal, or anything other then the Plaster of Paris.....just burnt right out, making a normal size hole in less than a year....:crazy: :WTF :surprised :lookinup:
 

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Discussion Starter · #9 ·
I have NEVER found any longevity to using blocking gaskets, sheets of metal, or anything other then the Plaster of Paris.....just burnt right out, making a normal size hole in less than a year....:crazy: :WTF :surprised :lookinup:
I think I read somewhere SS is the ticket.

What about block filler? Like they use in Drag blocks for water jackets.
 

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I believe those are the ones he used. What else might he look for? He did not re-torque for some time. Think that did it? Or are we lookung for something else?
Well you gotta figger that thin metal is trying to survive a constant pressure battering under extreme heat just inches from any of the exhaust valves...so it's seeing a constant ~1200f temp plus all the pulses with no backup....

I dunno jack about block fillers.....all I know is PLaster of Paris takes a damn nuclear bomb to kill it....

only one ting I remember ever THAT hard and tough, and i'ts been nearly 50 years since then....

:rolling: :rolling: :rolling:
 

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Discussion Starter · #12 ·
bird just now got home lots of traffic ave 25 from mv to san clemente temp stayed at 195 all the way. outside must be around 100 or more next time I will take that ice tea to as soon as I get a cup holder and the a/c fixed next week or next month I hope.
Dam. I was taking a nap and missed it.:laughing: :laughing:

How about a new manifold? Guys. What would fit with stock height? He has that ram air air cleaner.
 

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Well you gotta figger that thin metal is trying to survive a constant pressure battering under extreme heat just inches from any of the exhaust valves...so it's seeing a constant ~1200f temp plus all the pulses with no backup....

I dunno jack about block fillers.....all I know is PLaster of Paris takes a damn nuclear bomb to kill it....

only one ting I remember ever THAT hard and tough, and i'ts been nearly 50 years since then....

:rolling: :rolling: :rolling:

13 ?
 

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I think I read somewhere SS is the ticket.

What about block filler? Like they use in Drag blocks for water jackets.

The 300 series ss works, thicker the better especially with the thick gaskets.

Melting point around 1430°C
also resistant to the exhaust gas acids formed.
Good solution in a warm climate.
 

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Manfold is off and all looks good except the burn on the heat inlet. That pop sounds like a fail safe way to go
Question, If you wanted to remove it how hard does it get?
 

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Fel-Pro makes a gasket that has no heat crossover. I've got a set on my BB. Never had a problem with them burning thru. I've got rectangle port heads, but I bet they make them for oval ports too.

:cheers:
 

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