Thanks for the piston radius info.
My first reaction would be that if the cylinder reacts best with the radius AND then being lifted, this would mean straight away
that the cylinder was way low anyway , and would be better being lifted even with no radius.
If you plot in CAD what happens to the effective timing when adding a radius , it works out that the original timing is achieved
when lowering the cylinder exactly half the radius ( using a 0.7 feeler gauge as a stop , to change the piston movement by exactly 1mm ).
I have done alot of work on this in the kart engine and found that a full radius gives really good front side power increase - but at
the expense of too much overev power.
But I have just tested lifting the boost port as the latest Modena has it positioned 1/2 way between the A and B.
This did exactly the opposite - really good overev at the expense of front side power.
So Im thinking now that the radius , not cut above the boost , along with lowering the cylinder will give me mid range , then lifting the boost
will add the overev.
As you say , having to cut special heads to achieve this really is a pain.
But hey , if it was easy everyone would be doing it.
Ive got a thing thats unique and new.To prove it I'll have the last laugh on you.Cause instead of one head I got two.And you know two heads are better than one.
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