you have 2zzge engine. Toyota has sold those engines to Lotus. Lotus has designed a supercharger system as has Blitz. You can take it from 190 HP to about 220 HP. They have also played with the lift system making the 6000 rpm surge gone. You could do a 50 shot of nitrous and go to 240 HP.
The 2zzge, I have one in my Pontiac station wagon, is a high compression ratio engine, so adding boost pressure is difficult, that is why there is much room.
You have to look at it this way, if you take a small V8 and tune it up from the factory,, you'd expect the engine to have 660HP, a large block V8 would have to produce 800HP, there isn't a stock V8 that does that! The 2zzge is one of the highest HP to displacement ratio in the world.
Even a subie STI only matches the 2zzge as produced by Lotus in HP to displacement. The Honda s2000 is 237 HP from 2.2 liters, not even close.
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