Right now I have single turbo setup on my car. The turbo that i am using right now is T04S turbine a.r .63 and the compressor turbin a.r .70. The engine is boosting around 3500-3800rpm (the engine is start boosting around 2500-2800rpm and you will start feel the car pulling around 3500-3800rpm) all the way to 7000rpm.
I was thinking of making the car boost below the 3500rpm mark. So the idea is using smaller turbine housing. After checking the garret turbo T series journal bearing catalog, there are two turbine a.r that I am interested on the .48 or .58 still using T04S turbo with .70 compressor housing.
If I am using a.r .48, I am sure it will boost faster. I predicted the boost should come up around below 3000. And i think its going to be a fun car to drive cause the boost comes up early. But i am worry the power band will be limited and it will short of power before it reach the 7000 and also I am worry that the exhaust temp will go high.
The other option is going a.r 58, this option the boost will come right around 3000rpm-3500 ( just rough estimate). The power will still comes up early compare to .63, the power band will still go up to 7000rpm and the exhaust temp should be a problem.
For now the best option is using turbine housing a.r .58...but i am still open to other opinion....if guys have any other thought about the turbine selection just throw it on this thread.
Please stick with the subject discussion and do not ruin with comparing to twin turbo setup.....