47's are a stock GT500 injector. I don't understand how there could be driveability issues with an OEM injector.

60's should work fine too. If brent is telling you he cant make the car drive nice with 47's, I think it time to tell him to go for a walk...

Injector Dynamics:
http://www.injectordynamics.com/injectors.html

They make, hands down, the best injectors on the market. If you're putting money into a bottom end, don't skimp on whats putting that fuel into the motor. The 725's would be plenty for your goals and give you room to grow.

 

I know this is kind of an old thread but I had asked Brent about hp goals and he said it would be doable with my current injectors. He did say that they r not using the cheap injectors no more and have gone to the injector dynamics. He said they are pretty good but twice the cost. I did a search for them and it sounds like these r ahead of the game