Quote:

The engine shop has a set of 2 1/4 headers for the dyno, but I will have 2" in the car.

Your car headers will likely give more low end torque (below maybe 4500), but the larger dyno headers may give a touch more peak horsepower. (but they are likely too big for your application IMO) Too bad many car headers don't fit around the dyno.

I look forward to the results.

1993 Daytona, 5.50 at 130mph (1/8) 1.19 sixty ft (PG). Link to 572 B1 - Part 1