The Bosch FI is the limiting factor for you. You will probably have to switch to programmable FI to get significant power gains. Cams make a big difference. My 79 motor with Webers makes almost 170HP and there is probably some more to come when I start on the exhaust and the intake systems. It just has high compression pistons, RJR cams and a ported head. There is nothing else very high tech in it.
I have a Bosch injected 3L V6 and I have a good set of cams for it but I will have to install a programmable FI at the same time that I swap the cams.
76 Suzuki GT500
2011 Jaguar XKR
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