Supercharger 5 port cylinder head/cam thoughts.
Turbo Mini Forums

So, I have a blank 12G940 and am probably going to keep the valves the same. In my estimation higher lift should be fine keeping the valves (MG) the same size. Hopefully if I can get some +20 LC pistons (8:1) I will not be needing to sculpt the head too much. As I will not be running a turbo, I can get away with a lower CR as I should have no lag to make up for. If I need more CR, I will go along Vizards lines.

Ports are of interest. Very little has been written about supercharger heads and I figure that since I am a blower, I should not require any flow extracting at low revs. So I can use pretty big ports (bosses ground right away on the inlets and not so much on the exhaust). As I will have not very significant backpressure in the exhaust, I can run less exhaust valve bosses as the localised heating will be less. Hence achieveing a better head retaining the standard valve sizes.

Cam wise, I was toying with using the MG metro cam (20 deg more exhaust) along with 1.5 or 1.7 rockers. The engine should redline at 7000. (use 6500 safely) is this a good choice or do I need to get a 266, 276 for this job? I am trying to avoid funny expensive cam profiles.

What do you think of the above? Am I talking bollocks or is there some sense in there?
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Bugger off, I'm getting there.

lot of sense in there... You've obvioulsy got a good understanding of forced induction...

MG Metro cam is an excellent choice i reckon...

think of it as if your making for example 150 bhp are the standard ex valves and ports going to be big enough , really its big exhaust work because the intake charge is being forced in
if you go for a longer duration cam (266- 276)you lower your dynamic compression ratio , and so reduce the chances of pinking at lower revs
steer clear of the 1.7 unless you like a lumpy idle and valve guide wear