Choosing the correct exhaust housing for a turbo

Hello Guys,

I am busy buying parts for my 1000+WHP turbo Toyota 1UZ-FE project. The engine will be built, bottom end and heads. The heads will receive custom 272 Degree turbo cams from Kelford and I plan to spin it up above 8000RPM. The turbo I have in mind is the new G42-1450 from Garrett but I am not sure what turbine-housing I should order with it. There are a few options, a 101ar, 115ar and 128ar. How does one determine what housing will do the job, and does the housing influence the wastegate size?

Thank you for any advice in advance.

First step, I would suggest, is to contact Garrett and see what they recommend, as it is fairly new there may not be too many people familiar with the characteristics?

What are you going to be using the vehicle for? Normally a smaller A/R is for lower rpm boost, when exhaust gas flow is lower, and a larger A/R for high rpm use where the exhaust gas flow is high and the lower back pressure is desireable.

Hello Gord,

Thank you, that's good advice, Garrett should be able to point me in the right direction.