Originally Posted by ZMan8

Single turbo is really only up to 500 or 550 whp. After that, the turbo lag will be bad. Sure you can build a single turbo 1000 whp monster, but it will only be useable at the track and there will be very little power in a daily situation. Twins help resolve that with quicker spooling/smaller turbos while maintaining power levels. A popular mod for TT supra was to convert them to single big turbos. This made huge power at the top of the range by sacrificing low rev range power. Great for 1/4 mile and highway racings, not so great elsewhere.

Here's my logic:
If you want cost effective turbo kit and plan to be around 450-525 whp, get a single turbo.
If you want room to build the motor eventually/ get 600+ whp, then plan on investing in a decent twin setup.

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