How many of ya'll are auto-x'ing fox bodies with a PM3L? Thoughts?
After a handful of events, especially after today's, I'm not sure I want to stick with the trak-link as a TA setup that I currently have. On a grippy concrete surface today with decent tires (F1 Supercars, 295 rear, 265 front) and a co-driver to help keep them warm, my car just didn't feel grippy at all. I was 5 seconds behind (on a 70 second tight ass course) a really good driver and his stock 3rd gen FS car on old R compounds, which to me is ridiculous. I don't think I've ever been that far behind that ever guy before (2 seconds is normal if he is on R compounds and I am not).
Also, I let a bunch of other people drive the car during fun runs and I drove their cars; none of their cars so much as twitched when driving through the dirtiest portions of the course, areas where I felt like I was driving on ice. Granted, I drove an E30 on Direzzas, an M3 on decent tires, and a turbo miata, so I may just be suffering from the delusion that a fox body can be made to turn AND put power down. Those three cars were sick; if I lifted, the car turned, no matter how hot I came into a corner. The brakes on the Bimmers were redonkulous, btw way. ZOMG. I have 98 cobra brakes on my <3000 lbs notchback and they suck in comparison.
Anyhow, I think the short trak-link is providing WAY too much anti-squat (using Bill Shope's calculators, I calculated anti-squat to be 187%), which is making the car go into rear roll oversteer everywhere. Does that sound right to you engineering types? It feels great on the street but it's really really twitchy when auto-x'ing. I'm contemplating going with a PM3L for the last event of the semester just to see if I like it.
Or am I just describing something that gets fixed with a proper K-member? Could I have too much rear roll stiffness from the springs and big rear sway bar given my high anti-squat values?
Front: 300# coil overs (koni yellow SAs), ~-2.5 camber, ~+5 caster, SN95 control arms, stock 33mm sway bar (had a 28.5 mm bar on it but the car turned in so hard the ass end couldn't keep up at all. The car understeered a lot more today with the bigger bar), 94-95 spindles, bumpsteer kit, 17*9s with 265s, stock v8 k-member.
Rear: 350-390 conventional springs, koni reds, stock LCAs, SN95 axles, 18*9s with 295s, GW trak-link, Griggs adjustable PHB (bar set parallel to ground as high as I can get it, which is just below the seam of the gas tank, ~3/4 of the way up the pumpkin), 98 cobra 27mm hollow rear sway bar.
Last edited by aurdraco; 03-28-2010 at 05:35 PM.