What I'm trying to ask is, if you got a 20b and you want to set it up as an n/a now, what all would you have to do to boost it later? I'm only concerned with the engine itself right now not the turbo, ic, piping, fuel maps, etc.



Thanks

 

You'd want to leave the rotors as is. They have 9.0 compression which is close to 9.2 of the first 13Bs back in '74-'78. If you were going to run NA forever, I'd go with NA '89-'92 rotors which have something like 9.7. They'll still balance correctly with your counterweights.



My 20B is staying at 9.0 compression because I may one day supercharge or do a blow through turbo. Anything that's simple.

 

Thanks