6.5 wastegate

[grape]

How come a duramax and a powerstroke will make 300 hp with a wastegate and a 6.5 won't. What am I missing?

[gmctd]

Those series engines were designed to make power with a turbo designed for the application.
The 6.2L was designed for 135hp to meet corporate C.A.F.E. mileage requirements.
The '92 6.5L turbo was tacked on in an attempt to keep up with Ford and Dodge turbo'd engine sales
The GM turbo was designed to get boost up quickly at low rpm for driveability considerations, and was never intended to produce higher than 190hp, as the block water jacket was not designed to handle the increased heat of higher horsepower levels.

So, we do what we can.

[grape]

My original post was a little too vague. I really meant this to pertain to the 300 hp aftermarket buildups such as the power project, why have wastegated turbo systems been left behind.

[rjschoolcraft]

The Power Project truck has a wastgated GM8 turbo on it. John Kennedy's high power 6.5 has a non-wastegated turbo. The real issue is the size of the turbine housing and its flow characteristics. There are larger, wastegated turbos available that I believe could provide performance better than the GM8 and beyond 300 hp.