I am trying to figure out if a Porsche 911 GT2 could beat a Ferrari F430 or a 360 Modena in a straight line race.

Can a Porsche 911 GT3 beat a Ferrari 612, 599 GTB, or FXX in a straight line race?

None of those cars were designed for a straight line (drag) race, they were built to handle.

usually a Ferrari is faster than a Porsche,but Porsches are better made...
your Porsche will be able to beat the 360 Modena and possibly the F430 or the 612,,but not the FXX,OR THE 599 GTB Fiorano.

If you are comparing these cars side by side, your best bet is to find their 0-60 times, 1/4 mile times and top speeds. That should answer these questions for you.

Sites like wikipedia.com and general car sites will have most of this information.

if you like to flash, go with ferrari. if your more interested in the longer term (4-7 years) reliability and lower maintaining costs, go with porsche. as far as performance, the porsche could take the 360 and 612, but not the 599GTB or FXX..

The GT2, 911 Turbo, and GT3 all are faster in a drag race.
GT2: 0-60 in 3.5 seconds.
GT3: 0-60 in 3.9 seconds.
911 Turbo: 0-60 in 3.7 seconds.

F430: 0-60 in 4.0 seconds.
360: 0-60 in 4.4 seconds.

If it was the GT3 versus the 599, or FXX, the Ferrari is would win.
If it was the GT3 against the 612, l would say the GT3 would win, but it would be very close.
The GT2 is the fastest and most powerful 911 Porsche ever made.

The New 911 GT2 is would beat a 360 easily on a track, but would probably be pretty close in a straight line. The GT2 would have a better chance against the 612 than the GT3. It sounds decieving, but the GT3 can go 197mph while the GT2 can go 205 (which is comparable to the Carrera GT.) For the FXX, there is no way that any GT2 or GT3 could beat it. It goes 217mph. But l would never compare a Porsche to the FXX because they made a couple of these for a couple of investors.
Now if u were comparing on a CIRCUT, then the GT2 would likely win against the Ferrari is (Exept the FXX). Porsches r about speed, but moreover they r about handling.