Because Mike@GTM says:
Quote:
Originally Posted by Mike@GTM
Usually, good boost response, low boost threshold (boost comes on at lower engine rpms) and decent top-end power are what make a car fun to drive on the street or occasional track days. A twin turbo system does these things extremely well and cannot be beat…even by a well engineered single turbo system. The single turbo system has too many compromises to make as effective of a street setup.
Ultimately, for a 370Z on a stock engine, a single turbo is a very poor choice for a street driven car. It will have a boost threshold 1500 – 2500rpm later than twins, have poorer boost response and/or top end horsepower. If you are spending $5-7k+ on a turbo system, why throw away so much performance by using a single turbo system?
|
I did this:
And zoomed in on the deltas:
So in the absolute best region for the GTM TT, you are talking 150 RPM (200 at best). And this is GTM's latest/greatest for which I haven't even seen pricing or availability and the GTM dyno is with no mufflers.
Top end horsepower isn't all that much of an issue if you aren't building the internals for it. The Boosted kit with a different housing is rated at 700+. I'm willing to bet 98% of every boosted Z will never see those numbers. It's a different conversation.
I won't get into install/cost here, but that's a no brainer.
Dyno charts used:
Boosted Performance single turbo build
GTM Performance Engineering: GTM TD05 16G Test Results 91 Octane 7AT
Sorry for the massive picture sizes, but if I scale them weird things happen to the grid.
