Hap,
How much more hp/tq, did you get from the tune? Over the product claim of 60hp/?tq...
The price seems nice, but. You might make close with super six heads less $$. And no Possible detonation, and blown head gaskets. I would like a power adder, but. Im leary of the 9.7 compression and high top piston ring location.
Im a put a foot in it often guy. I prefer to build from the bottom up for power adders.
I did this with my '94 stang cobra motor. I know 6psi would have been very safe. 8to10 easy also. Just never spent the extra $$ for the huffer..