Please share the suspension setup on an original spec chassis and explain how it differs from the FGT and is designed for bias ply tires. The numbers I've seen for torsional rigidity showed a ~30% increase for the FGT but given it weighs 1500lbs more, it's probably is a wash given the forces in play.
Your experience on the track is anecdotal at best. There are a couple guys on the GT40 site who have their cars setup for track that state they are running with GT3's all day long. I would guess brakes would be the limiting factor given the size difference.
Can you describe the GT40s you lap at Willow because I would love to hear their side of that story. Given the limited number that run there it should not be too hard to figure out who they are on the GT40 site.
If you want a soft seats, A/C, cup holders, satnav, and a nice stereo for your lady gaga tracks, then a modern sports car is the ticket. If you want a no compromises, visceral race car experience that will leave you exhausted, sweating hot, deaf, and your eyeballs rattled, then there are few options better than a GT40. I would not trade mine for my old Ford GT in this lifetime and I liked my FGT a lot.
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