Performer RPM modification

-
D

DDS74

Active Member
Joined
Dec 29, 2012
Messages
36
Reaction score
1
Location
Land of ice and snow
So as my 383 build is progressing I have run into a bit of a problem. With the Indy heads and valley plate the EGR crossover on the intake hits the valley plate, and won't let the intake anywhere near the heads, has anyone run into this problem before? I have no problem cutting it off, but if it won't work I'd rather sell it as an unmodified piece. So I guess I'm just curious if this problem has been dealt with before.
 
Yes, ether run an OE bath tub gasket or get the valley plate with the one side that has the builtin depression to clear dual plane intakes.
 
The bath tub gasket will not work with the indy heads.
You will need to machine the intake manifold , modify the valley plate, or go with a single plane manifold.
 
Indy heads are designed for high performance use so they don't expect that you'll be using an intake with exhaust heat. Most people want to get rid of the exhaust heat under the carb since they want the intake as cold as possible for max power.

If you have a weird combination where you want high performance heads plus exhaust heat you'll just have to fabricate a solution. I've seen guys modify the valley plate with a little cup in it but that seems like a lot of work.
 
william said:
The bath tub gasket will not work with the indy heads.
You will need to machine the intake manifold , modify the valley plate, or go with a single plane manifold.
Click to expand...


Thanks for the correction
 
I would not cut that intake. It will be worthless if you do. They make Valley pans that have the clearance for the RPM intake. 440 source sells them.
 
The only time the RPM intake would be worthless after having been cut, would be if installed on a set of factory iron heads. All aftermarket aluminum heads have no exhaust crossover passages.

Before buying the 440 Source dual plane pan, check with 440 Source to see if their valley pan will even fit the RPM intake, because, some dual plane intakes (the 6-pack in particular) do not fit the 440 Source valley pan.
 
Mill the heat passage off the intake. It'll be far from worthless. It's more problematic when people mill the manifold mating surface for clearance when they deck the heads. S/F.....Ken M
 
You must log in or register to reply here.
-

Back
Top