LT1 intake on LT4 heads
Re: LT1 intake on LT4 heads
Originally Posted by Chris 96 WS6
.... I don't think there's enough material in the LT1 intake ports to open it up enough to match the LT4 head ports.
Originally Posted by Loadre
Is there any possible way to make this work?
Did you plan on raising the port roof (in intake) to match the port height in the heads? If your intent was to 'raise the roof' of the manifold port, use of the OEM unmodded LT1 intake, will result in non sufficient material above the port to raise it the amount necessary. If there would have been no intent to port the LT4 intake (if you had one), then the LT1 intake will fit fine, as ports are the same height, width and location, as an OEM LT4 intake. The use of an LT4 manifold ALLOWs the roof to be raised to match that of the LT4 head ports.
One more variable. I noticed you would be using a '94 LT1 manifold. True? In that case, double check your port openings in the manifold. They should have a nice crisp rectangular shape to them. If it is, and they are as expected, those intake manifold port openings are actually LARGER than the ports of an OEM LT4 manifold. Did you, or do you plan to port the LT4 heads? If you scrutinize your OEM 'as cast' head ports at the flange, the matching short side wall (curved pushrod side wall) is tipped (angled) in toward the top of the port. IOW, not a true rectangular shape to it. This will match the shape of the port in a virgin LT4 manifold. This shape is also consistant with the later ('96-'97) LT1 intake manifolds. This means.... if you plan on using unported LT4 heads, the (your) manifold port will overlap on the width of the LT4 head port. Not a good mismatch. Ironically, this same 'untrue' rectangular shape is normal for the LT(1) head as well. This means, your original OEM engine from the factory, had this same head/manifold port mismatch. FFT.
This info and more, has been posted several times in the past, if anyone was so inclined to do a search (both here and in 'advanced tech').
Last edited by arnie; May 19, 2005 at 08:58 PM.
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