Not looking to increase capacity at the moment.
IF I was going to do that would probably just throw a Jag supercharger lump in as you can pick them up for £3000 for the whole car lol.
But thanks for all the inptu. Loads to think about.
all my engines are ballanced crank pulley and flywheel as a matched set rods end to end to 1/2 gram same to the piston crowns
three angle valve seats mild bell of head through to full ported
piper 270I cam standard valve train parts
matched ports on the inlet and exahust manifolds can even full flow the inlet too
on a 3.9 will give 230-265 depending on the heads and inlet
on a manual flywheel it looses 4lbs of weight! on a auto it is just balancing due to it being poorly balanced
mines kicking out 250bhp on and off the road it is all grunt low down and still very tracktable
My full blown engine 4.6 engine with fully ported manifolds and heads and big valves and pocketed pistons and piper 285 cam pumps out 340 bhp in a p38 it is good for over 23 mpg though one customer got got 25 on a run up to Scotland at a constant 70!
I would go the lsi route or even a chevy all alloy crate motor but again it is not cheap