FLD Does anyone know what the holes at the sides of the exhaust ports do? The original manifold blocks them but a larger bore aftermarket doesn't. Just thought I'd check what they do / are for. Can I fill them with block-fill? Cheers
FLD Sorry should have been more clear. Its not the channel for the egr, they are little holes around 7mm (some square some round) either side of each port. The only thing I could think of was they are for even heating of the head casting dunno.. dunno.. Hence my asking. They are around 3" deep when I poked a welding rod down but they might curve off.
FLD Ah, thats interesting. So if these kink in to just behind the valve I assume I can just leave it open as long as its collected by the manifold runner. I could make some press fit plugs if need be. Have these been blanked before?
alanoo Best for the flow would be to block them from the valve side (not the manifold one) We blocked them with an ultra high temp epoxy, but it was still too hot for it (even if it was a 450°C one)
FLD Hmm, might have to have a look at that. Do you reckon it'd weld? I've never welded alu cast via lost foam before. dunno.. Does it behave like normal cast ally?