intake gasket ?

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j.d.duggan

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does someone make a intake gasket that hides those uuuugly horseshoe holes in the center of the head?don't really get why there left open on both heads,I was told they had to do with the heat riser on a stock intake.but they look like crap and I,d like to cover them up if possible.thanks:mad:
 
Aftermarket intake gaskets might close/block the actual heat passage beneath those vents. I haven't seen any gaskets that cover the vent. To bottle up too much heat there wouldn't be good.
 
does someone make a intake gasket that hides those uuuugly horseshoe holes in the center of the head?don't really get why there left open on both heads,I was told they had to do with the heat riser on a stock intake.but they look like crap and I,d like to cover them up if possible.thanks:mad:

Closest thing I know of is the Felpro SFL1213S3 gaskets.
(FYI Aftermarket heads don't have those holes)

intake.jpg
 
As long as you block the heat to the intake you will be o.k. but if the port is open I would leave the vent open too. I have used a thin piece of SS to block the port because over time the paper gasket burns through.
 
so the horseshoe shaped hole is a vent?what kind of heat comes out?

Hot exhaust gases go through the intake, when the heat riser is closed on your exhaust manifold the gases are forced through the intake manifold. That's what kind of heat. The vent helps cool the port.
 
Yep, it's in between the center exhaust ports.
 
If blocked off,with headers and 3" pipes would it ever be a issue?
It's a void between the ports. It's not on the header side of the head. It was put there for a reason by engineers a lot smarter than you or I. Leave it open and let it work.
 
I thought they said to leave it open.street car,want it to worm up properly so don't I need to leave it alone?
 
Let those puppy's breath!
 
That's why I used a thin piece of SS, I think it was 28 gauge, like .015"
on the head side of the gasket and it wont burn through.
We aren't talking about the heat riser passages but the voids in the middle of the heads on the intake side.
 
We aren't talking about the heat riser passages but the voids in the middle of the heads on the intake side.

If there is no gas flowing then there wont be the heat, Right. Block the heat port to the intake and then you can block the vent.
 
It's not as much of a "vent" as just open space to let the iron around the crossover port expand from the heat and not cause cracks.

Unless you plan on driving in sub-40-degree weather a lot you don't need the exhaust crossover open especially with an aluminum intake manifold (aluminum transfers heat from the engine up to the plenum/carb area much quicker than iron). With today's crappy ethanol gas it'll just cause headaches from overheating the carb and boiling the fuel all the time.
 
It’s just a chamber like stated above. I have filled one with Belzona super metal epoxy to fix this on a spare ported x head. Plan to drill and tap right through into the heat cross over port and seal a long stud, run a thick rocker shaft and it should be fine.

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I'm betting Ma Mopar put that chamber around the crossover passage in there just to save weight. Less iron = less weight = less cost.

Daily driver with old pump gas, and very low outdoor temperatures, you needed the crossover. With today's gas you probably don't want it. Remove the flapper in the RH exhaust manifold, and block off the intake manifold passages on cars that are driven in nice weather only, have an electric choke, or EFI.
 
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So the thread wasn't about the exhaust gas passage but about the atmospheric relief in the casting that allows absorbed heat to escape. One can effect the other though.
If you have a working heat riser in the right exhaust manifold, bottled up exhaust would probably get hotter than flowing exhaust at right head, until the heat riser opens anyway. Right head hotter than left for a time? Of course if you run free flowing headers, no heat riser, there probably wouldn't be a lot of exhaust gas pushed upward anyway. Even better if you have a X crossover downstream in the exhaust ( levels the back pressures L&R ).
Back to with working OEM heat riser, block the crossover passage bottles the heat up. Fill or otherwise close the vent that lets the heat dissipate from the casting... I wouldn't.
I did see a copper mesh material poked in these vents once. That owner cut up a pot scrubber? Stopped his small parts loss anyway. Hand form polished stainless screens for "looks"?
 
So the thread wasn't about the exhaust gas passage but about the atmospheric relief in the casting that allows absorbed heat to escape. One can effect the other though.
If you have a working heat riser in the right exhaust manifold, bottled up exhaust would probably get hotter than flowing exhaust at right head, until the heat riser opens anyway. Right head hotter than left for a time? Of course if you run free flowing headers, no heat riser, there probably wouldn't be a lot of exhaust gas pushed upward anyway. Even better if you have a X crossover downstream in the exhaust ( levels the back pressures L&R ).
Back to with working OEM heat riser, block the crossover passage bottles the heat up. Fill or otherwise close the vent that lets the heat dissipate from the casting... I wouldn't.
I did see a copper mesh material poked in these vents once. That owner cut up a pot scrubber? Stopped his small parts loss anyway. Hand form polished stainless screens for "looks"?
If you block the intake heat passages, the heat riser should be removed or, at least, wired open.
 
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