kawi600

dont think there is a real substitute for twins at higher HP. You need the airflow that only a large single could provide and the low lag only a small one could manage. Makes sense to compound the two.
For the 350-550hp range you could get a phat shaft 62 or something and probably be pretty happy with it. It will be a tiny tiny bit laggier. You wont grow out of that turbo until you have some serious fueling in place. You can also go with water/meth and extend its use a bit further.
You can use the AFC on a 12v to limit the pre-boost fueling to a haze which works well. But then you lose the ability to smoke out tailgaters. =)
Its all a balancing act.

dieselman2300

WOW you got the shaft, unless they are gold plated.

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