AK71CutlassS

Was mocking my intake up to Engine. I'm looking at .007 on one side of the intake to head clearance. Do I need to surface the intake ?? Also on the height how do I know if ports are matching the best they can?? I'm just trying to figure this out the best I can... it is a performer intake to Pro comp heads. Heads are from Mark

wr1970

If it was.07 i might worry and shave the intake to fit! You are ask about.007 !That is very minor amount.The gaskets will eliminate that amount of mismatch.JMO

442fanatic

When I had my 455 built, the machinist decked the block, heads, exhaust side and intake side. Not sure if they touched the intake.
Result was great for heads and exhaust. But with oldsmobiles that intake angle is touchy. The stock intake valley pan gasket didn't seal and had vacuum leaks. I then put in a rebuilders intake kit from Rock Auto. I then gained a coolant leak even after torquing the intake down 5 lbs over, then an additional 5lbs over.
I found later that Joe Mondello racing makes a 3 piece intake kit, which made the valley pan independent from the intake gaskets (which were thicker) and used sealant. I had the local mechanic who was a big racer in the day do that repair, as these issues came up after the paint work was done...

In short I would go with that Joe mondello 3 piece kit however you shave the intake to compensate for the angle issue due to whatever machining you had done to the heads and block.

Fun71

I always use Mr Gaseket intake gaskets and never had any issues with sealing on my 350. Spec sheet shows they are .060" thick so they can fill a gap fairly well.

The 455 uses #404 and are available just about everywhere.

https://www.summitracing.com/parts/m...ake/oldsmobile

http://www.oreillyauto.com/site/c/de...2293&ppt=C0026


http://www.autozone.com/external-eng...93708_88261_0/

http://shop.advanceautoparts.com/p/m...404/17360257-P

joe_padavano

Mocked it up how? Did you just set it in place? Use a gasket? If so, what kind? Did you torque the bolts? Did you use the rubber end seals? All of these factors affect fitment. Are you saying that the intake bottomed on the front/back edge rails of the block and you had clearance between the intake and the head? If that was metal-to-metal, you might have a problem. Have the heads been milled previously?

AK71CutlassS

Mocked up just metal on metal intake to head.007 on one side of intake to head
. 1/8 inch gap on to ends to be filled with a bead of rtv once I figure if .007 is ok. Yeah maybe with the gasket layed in place it will be ok. ???

joe_padavano

I still don't understand. If you just lay the intake in the valley, it sets on both heads. There is zero clearance. Are you saying that you threaded the bolts in, and the intake is resting on the bolts, which is how you get clearance on one side?

AK71CutlassS

I layed the intake in with no gaskets. There is normal gap on each end. That isn't the issue. I have a .007 gap on one side of the intake where the ports are at .007.

joe_padavano

That's what you're worried about? That's called normal production tolerances. Stop losing sleep over this.

AK71CutlassS

Haven't loss a minute of sleep

wr1970

Just like i said before not a problem. I understood you from the get go. Put on your gaskets game over it isn't a problem.

74sprint

As for port matching with a performer intake I have used 2 methods, with and without gaskets. With all gaskets in place, fiber gaskets glued (RTV) in place on the head and dry use some wet paint on the intake side and very carefully place the intake on, then very carefully press down on the intake, don't let it move in any direction but down. Then very carefully lift the intake up, this is only good for major misalignments. The other way is to place the end gaskets on and put a thick covering of Play-Dough on the head and press the intake down as above. Once again this is only for major misalignment, if you find minor misalignment say 0.030" then don't worry about it unless your going for max power above 6,000 rpm, you won't notice it.


Ray