[Z OH 6]

Originally Posted by radz28

You're at like 700, aren't you?

700whp, yes. Full bolt-on, 93 octane. I couldn't use any more power on street tires.

[KingLT1]

After tuning several of these cars imo going to a 2650 is not really needed unless you plan on going north of 700-750whp on Pump 93 bolton only or 800-850 on Ethanol. Ethanol will handle higher blower temps and maintain timing, so you can push the 1.7 further. Meth injection allows the same. That's how guys hit 1000whp. They need meth and E. If you are a road course only car limited to 93, then the 2650 makes more sense. So it all comes down to the application. But for most builds a ported stock 1.7 is fine. I seen 2-3 cases where guys swapped to a 2650 on a bolt-on car making around 700whp and went slower in a drag race because of power lost under the curve. The 2650 is barely working at that power level. But those are cars running a tire also. If you limit the car to 220 wear tires, then a 2650 could help there as well from the softer hit. So again it all comes down to the application and end users goals.