I, personally, feel as though 8:1 is far too low of a compression ratio. That thing must be a dog when not in boost... Good thing it has a positive displacement blower on it.
If you aren't cramming another atmosphere (15psi) or more into your engine, there is no reason not to maintain a 9.5+:1 compression ratio.
My advice to you is to keep the maggie, port/pulley it to around 12psi, add a second heat exchanger(*), and bump your compression to 9.5:1 or 10:1with new pistons or decking the heads (or a combination of the two).
Note (*): second heat exchanger...
Normally, the coolant leaves the blower, flows through a heat exchanger (HX) and into the reservoir, then from the reservoir to the blower.
In my proposed configuration, there will be a second heat exchanger placed between the reservoir and the blower. So:
Blower -> HX -> reservoir -> HX (#2) -> back to the blower.
The second heat exchanger doesn't have to be nearly as large as the main (1st) HX. But should still be large enough to make a difference.
If you aren't shooting for 30psi, and if you ever plan to drive it on the street, do yourself a favor and fix that 8:1 compression ratio first thing.
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