2.25" or 2.5" exhaust?

I vote for 2.5"

a single stick of 2.5" has a flow capacity of about 330hp airflow wise....with 2.5" duals and your statement that you will run a 273/318 forever...you will never outflow the capabilty of 650hp of air that the 2.5" pipes can handle.

2.25 will limit you to 450-500hp before it becomes a restriction.

How do I know all this? My turbo 4 cylinder days recall clearly the .70 second gain I recieved by installing a SINGLE 3" exhaust pipe over the aftermarket 2.5" I put on a year before, and 2.5 seconds faster than it would go with the stock 2" exhaust system.

Trap speeds prove I was making notable Hp gains:

1998 Eclipse GSX Awd Turbo

100% Stock - 10 psi boost - 14.97 @ 88 mph

Stock Engine and exhaust, upgrade turbo 16 psi - 14.3 @ 94

Stock Engine, 2.5" exhaust, 16 psi, - 14.0 @ 97

Stock Engine, 850cc injectors, Front Mounted Intercooler, 22 psi, 3" exhaust 13.31 @ 107

THEN,...Customized Programmable ECU,Two Step Rev Limiter, 15 psi @ 6000 launch, 25 psi - 12.74 @ 112

http://www.youtube.com/watch?v=unL4IIMMlxg

Nuff said.