dvw
Well-Known Member
It's not always possible to cut the intake side. In my case my Indy heads are 57cc. That leaves the intake face to thin if cut far enough for the intake to fit. How do you figure it out? Scribe a line across the top of the intake bolt holes on the heads. Continue he mark around the corner of the intake Parallel to the intake bolt holes on the front and rear of the heads. Make the exact same marks on the face of the intake manifold. Now set the intake on the engine. Measure the distance between the two lines at each corner. Average all the measurements. Averaging eliminates error if the manifold is not sitting square. Add the thickness of the gaskets to your averaged dimension. Example, RF .065", RR.070", LR .055", LF .050". = .240"/4 =.060". If the gasket is .040" thick. .040"+.060"=.100". Cut this total amount from each side of your manifold. The manifold will now fit. I had to trim mine .100", it fit perfect the first time.As part of the machine work on my 440 the machine shop decked the heads to true them up but, unfortunately they did't record how much was taken off. I seemed to recall (it's been months ago) when the called to let me know they needed to be decked I asked them if the intake needed to be done at the same time and they told me they didn't think so. Well I went to install intake (Edlebrock Performer) and as you would guess it doesn't fit. To get an idea on the difference I installed the bolts on one side and it looks to be about an eighth of an inch from lining up with the holes on the opposite side. The eighth is on the top of the bolt holes.
I've tried it with the paper gaskets on both sides of the valley pan, one paper gasket, and no gaskets all fits about the same.
THe machine shop guys are not giving me a hard time, a little embarrassed about the recording mistake and one fellow suggested I elongate the bolt holes in the intake (which in looking at it would probably work) but before I do that I thought I'd post up and see what your thoughts are. I'm sure they'd cut the manifold for me if I asked them but what would you suggest be cut from each side?
Thanks
Doug














