The exhaust is completed and in the car so it must all fit, I don't think it would be possible to do a proper four into one equal length, on the R side anyway. As long as it sounds good, is not too loud and does not drag on the ground I'm happy. 400-450WHP will do me fine so that should not be a problem with that exhaust, have now decided to just get the engine running, lay it up for a few months, then I'll be able to get back to it later with a cam change and whatever else the engine needs to reach the power target plus a dyno tune of course.