Big Block Exhaust Crossover Blocking Question

[A383Wing]

What do you guys use to block off the exhaust crossover on the intake manifold on a big block?

Bryan

[Ghoste]

I use the Fel Pro valley pan that has that portion solid.  Years ago I used to jam the crossover with tin foil but the blocked pan is soooo much easier and better.

[no318]

Me too.  The application was for industrial/power unit engines, I think.

[A383Wing]

ok..looked online at Schucks stores...FelPro #1214 for $31 has valley pan blocked off at the exhaust and also comes with 4 fiber gaskets as well...

may have to order one....

reason I asked was I'm trying to stop the long hard hot start in the Daytona after shut down

[62 Max]

If you buy it,throw away the paper gaskets if you have a iron manifold.

[A383Wing]

If you buy it,throw away the paper gaskets if you have a iron manifold.

have Weiand 8008 aluminum intake on the Daytona...use them or not?

[firefighter3931]

I've never used the paper gaskets....aluminum or iron intake manifold. Unless the intake surface of your Wiend has been cut you shouldn't need them either.


Ron

[A383Wing]

I've never used the paper gaskets....aluminum or iron intake manifold. Unless the intake surface of your Wiend has been cut you shouldn't need them either.


Ron

nope...underside of intake has not been cut...and I'm just using the metal valley pan gasket on there now....seals just fine

[firefighter3931]

I've never used the paper gaskets....aluminum or iron intake manifold. Unless the intake surface of your Wiend has been cut you shouldn't need them either.


Ron

nope...underside of intake has not been cut...and I'm just using the metal valley pan gasket on there now....seals just fine

You're good to go then 

Another item to consider is a carb insulating base gasket which helps with conductive heat. Keeps the carb & fuel much cooler. 

http://www.summitracing.com/parts/EDL-9265/



Ron

[A383Wing]

yea..already have a carb insulator...it's like a sandwich style, gasket, aluminum spacer, gasket, spacer,......and so on...

also gonna put the insulation back in under the intake as well...see if that helps.

[Ghoste]

Personally I think that noise insulation just transfers more heat (physical connection instead of air blowing through).  But try it and see.

[tan top]

Personally I think that noise insulation just transfers more heat (physical connection instead of air blowing through).  But try it and see.

yep thats my thinking on this also   

[c00nhunterjoe]

The spacer being made from aluminum is doing nothing to stop transfer. It must be made from a non conductive material to keep the carb cool

[A383Wing]

it's not a piece of aluminum..it's layered with gaskets inbetween

[Ghoste]

Are you talking about the foil wrapped pillow that lies on top of the valley pan or something else?

[firefighter3931]

Personally I think that noise insulation just transfers more heat (physical connection instead of air blowing through).  But try it and see.

yep thats my thinking on this also   

Ghoste & TT are correct ! 



The foil wrapped pillow is for engine noise reduction. All BB intake manifolds are air-gap (by design) so the last thing you want to do is fill in that gap with a conductive material that will transfer heat from the valley pan to the manifold. 


Ron

[62 Max]

But,Chrysler engineer's didn't have a problem with it.

[Ghoste]

They also had better gas.  More than a few of the problems with vapor lock today are caused by the oxygenated fuels designed for high pressure fuel injected systems.

[firefighter3931]

They also had better gas.  More than a few of the problems with vapor lock today are caused by the oxygenated fuels designed for high pressure fuel injected systems.

Exactly ! 

The junk they pass off as fuel nowadays hardly resembles the gas they sold back in the day. 



Ron

[A383Wing]

The spacer being made from aluminum is doing nothing to stop transfer. It must be made from a non conductive material to keep the carb cool

here is what I have on the Daytona...it's not a "one piece" item

[Ghoste]

Okay,we're definitely talking about two different things then.  I thought you were referring to the insulation that goes under the intake manifold.

[A383Wing]

Okay,we're definitely talking about two different things then.  I thought you were referring to the insulation that goes under the intake manifold.

we were talking about that also...I often wondered if it would be better to leave the 'glass stuff out from under the intake so air would pass through..or put it back in as Ma Mopar did back then

[Ghoste]

Much better, take it out today.   (Edelbrock came up with a great idea for an intake manifold a few years ago... they called it the Air Gap)

[HeavyFuel]

OK.....old thread...but that's OK.

So we can cool down the manifold with the block-off gasket.  But doesn't this effect the stock choke, keeping the carb closed up too long, maybe even all the time?   How do you solve that?


I'm kinda wrestling with this right now......install a block-off gasket and modern carb with an electric choke, or keep it all stock, and take my chances with overheating the intake/carb.


??

[Chryco Psycho]

electric choke or set the choke mostly off if you only drive it on warm days your really do not need a choke