Lotus Super 7. There is absolutely no way to compare the genius of one of Colin Chapmans "Light makes Might" designs, with a Mark.
"Keep making (the part) thinner until it breaks, then make it one size bigger than that". I love Chapmanisms. "There's no suspension problem that can't be solved by stopping it from moving".
See below...
As a matter of fact, I don't think there is any magical suspension setup on our 4000# luxury barges that is going to make our cars outhandle a Mustang.
The complexities of mechanical grip and high speed cornering aren't as simple as weight, a road course isn't an autocross.
I'll see if I can condense some of it into bullets without writing a huge internet:
-Width: Our cars are wider, and we can fit more tire. I've run 275's on the front with an 03 Cobra rim.
-Areo: It matters a lot more as you get going a lot faster. 14 second cars dragging to 90'something mph aren't moving as much air as they are at 120/130.
-Suspension: Something I'm sure everyone here has noticed is, despite being wider, mustang headers don't fit. We have less engine room because our suspension takes up more room. Longer control arms result in more grip than shorter ones, having to do with the angle of the tire as it compresses (since neither cars have equal length CA's).
-Weight: We've got more to loose. Our cars employed lightweight materials to counter the additional weight of all that luxury stuff. That's why out curb weight is so close to the MN12 with less stuff in them. The "Rip it all out and start cutting" treatment will remove more weight for our cars than from a Mustang, it's theoretically possible to match their weight. Being bigger doesn't matter if you're full of air.
I'm not talking out of my arse either, this is something that I've done time and time and time again, albeit in an XR7 with 5.0. Mustangs and Camaros simply do not compare. Stock Corvettes also had trouble, though Z06's fared better. Small cars like Miata's and RX7's may "technicaly" handle better, but my street-tire lap times were equal or faster than their race-group times. The car needs some balls at some point.
If you want to dominate a racing class, cut a Gen 1 Mark and feed it a 9:1 power to weight ratio. Cobra Brakes and wheels, Koni Yellow (or equivalent) shocks, and a stout 5 speed. I'd recommend swapping to a simple 5.0, it's cheaper and easier. By cutting, I mean going after it with a saw.
Enter it in American Iron:
http://www.nasaponycars.com/
Doing HPDEs in my street-driven 230rwhp XR7, my lap times were quick enough to not-finish-last.