Tossing Around 273 Ideas

BTW, I ran 8.2:1 CR for several years on a rally car with a 14-15 psi boost limit; that particular combo would detonate at boosts up around 17-18 psi with pump premium fuel; going higher on boost would have required non-pump fuel mixtures. So that is one reference point for a limit to the boost vs SCR. The 8.2:1 SCR made the 'before-boost-comes-on' performance to be a LOT better than at 7.6:1 SCR or 7.2:1 SCR which I tried in the same engine. So getting that SCR versus boost limit balance correct is important, in my experience and in that application, which is what might be characterized as mixed street and endurance racing.

Is this setup going to mainly emphasize drag racing? That makes the choices a bit different, IMHO.

Also, there are a lot of different turbo designs and just small tweaks in the exhaust side wheel can make a big difference on how the turbo comes on at low RPM's. So I would do a lot of reading on that over on the 4 banger turbo forums; they seem to pay a lot of attention to that aspect.