GTM Performance Engineering: MHI Twin Turbo Official Release

Originally Posted by wagz

Can someone please edumacate me on internal and external waste gates and why the price difference between these and turn-key.

External wastegates are ideal, but are more expensive due to more parts and plumbing. You'll never have to worry about boost creep, and boost control will be rock solid. Internal wastegates will work fine. Most OEMs use internal wastegates. It's just not ideal and you may have boost creep.

Also - am I understanding correctly, that clutch and other temp issues may arise from this kit? For the sake of conversation is it best to replace the clutch prior to this install and get better cooling options with this install. Or can one reasonably install the kit and anticipate these items as long-term (1yr+) maintenance costs.

You need an oil cooler. Full stop. A radiator is a damn good idea. These turbos are oil and wated cooled, so both fluids are circulating through the center section of the turbo. You're asking the OEM cooling system to handle more heat than it was specced for, and this car already runs hot. Plus you block the radiator with an intercooler, making matters worse. You may be able to get away with the stock clutch for a while, but it will wear out faster than a NA car.

Originally Posted by Chuck33079

You're better off IMO saving for longer and getting every single supporting mod you may need rather than doing it over time.