I have a z and my buddy has an ISF. He has pretty deep pockets (at least more than me)
I bought my Z used and have quite a few bolt ons. The ISF is a V8 and does have about 80 more horse power and you can feel it. Power to weight ratio and/ cost and 0-60 was not that much different. We track our cars about 5-6 times a year and I can keep up with him unless it is a real long straight away. As long as I can keep the engine spooled up , I can hold my own.

As far as performance. You can only change the suspension /wheels /exhaust. My buddy contacted SAAD racing and they as well as other companies have said that without spending thousands of dollars cracking the built in computer, there really isnt much more to do to the car.

The Z however, the sky is the limit as long as you have the money.

I'm no expert, just sharing what I have been told and learned.

Bottom line, If you like it and have the money , get it. Just don't expect to modify a whole bunch of things.

They are really sick looking cars.

^Agree
Excellent points


The ISF isn't a whole hell of a lot faster in most situations in DD... Cutting people off on the freeway... I mean merging on the freeway... Easier on the ISF

And there are no "tunes" but they make headers, exhausts, intakes, and other simple mods which REALLY open the ISF up...

There IS a rear mounted turbo kit... At a cost of 20k, and I only know one person who has it. He has no issues with it, just doesn't drive in the rain, lol, but he has 650+WHP, and his car sounds like "Amplified thunder" as Jeremy Clarkson says

Different strokes for different folks