Errrr.... after getting a new RPM Airgap intake from edelbrock after the last one was trash, (I.E.- wasn't machined properly) I now have head problems. Wish I caught this before they were put on. I ordered the Performer RPM Aluminum Heads for my 302 converted to a 347. It's got the top end package from edelbrock. The problem I'm having is, only 2 of the coolant ports from the heads to the block are in the same location. Had I not caught this, the intial fire would have warped the heads most likely. Only the rear 2 coolant ports line up with whats on the block. The other 8 or so do not. I'm thinking I may have to drill the block to tap into the coolant system and let the gasket hide the other ports i can't use. I'm running out of options. They only sell 2 types of Performer RPM heads for a 302, the ones with the 1.90 valves or so and the 2.02 ....none of this should indicate they're different. In summit catalog, it says for 1982-95 302 but I was assured it would work, and all 302 blocks were the same except front and rear sump oiling, and 1 and 2 piece seals. and conversion to roller cam etc... Now, i know there are people in here that have rpm head son there 302's, but are any of them older style blocks? I would almost be sure of it. Mine is a 1971 block. And another thing that is fishy, the rpm heads say they're for 1982-95 and the regular Performer heads say they're for 1965-95. I only have 1 box the heads came in, and I don't know if edelbrock would take them back now. Especially after being installed and what not.... this is soo frustrating. Any suggestions please... if you have rpm heads on a older 302, whats wrong with mine?
Which coolant ports are you speaking of? I have two sets of RPM heads, an early set (6025) and a newer set (5 digit part number) and both are on early blocks. Both don't line up perfectly with the coolant holes in the deck surface but there have not been any signs of overheating whatsoever. In fact, they run cooler than any iron headed motor I've ever run.
they only use the rear ports on ford. the path of coolant flow is from the water pump thru the block, out the back of the block thru the cylilnder heads then to the intake and then the t-stat housing. thats why the cylinder head gaskets are marked front. and one ends up going on what looks like upside down. if you look at the gaskets you will see that they only have coolant ports on one end. i bet they match your heads.
I am running the 6025's on a '68 block. No issues. They did come with some instructions on drilling holes in the block, but I did not do it after checking on here.
In the Performer heads, the 62-95's have screw in studs, the 82-95's are drilled and machined to be used with pedestal mount rockers, that's the difference. The RPM heads lack the exhaust crossover passages. As with any head swap, the coolant port alignment needs to be checked, but the front ports don't need to align with those in the block. The top middle ports will need steam holes though to prevent steam and air pockets from forming. Wouldn't hurt for the middle bottom ports to be open too, but that may not be absolutely necessary
they all line up fine, except as stated above.. make sure you get the head gaskets put on right.. i had that problem when i first built my engine, and the blow off at temperatures is enough to scare the crap out of you when driving down the road.
Mine came with instructions to drill the steam holes. Afte talking with others on this board and my machine shop I did NOT drill them. I have not noticed any negative results of this. Scott
