Since Im buying new tires I'll go ahead and get the car realigned. Are the factory specs still considered optimum, or are there improved ones? My car still has an issue with tramlining on grooved roads. Other than that it's handling fine. thanks t
There was this little incident on Saturday that resulted in the tires being less-than-round now.... I could probably get them shaved but they're already getting thin, they've been on there over a year
I've always found that -1.5 deg rear camber spec just visually unappealling, and, IME, if you're not doing 10/10th, the inside rear tire shoulders wear prematurely (my-ex 308 came to me with 16" BBS 308 QV-sized wheels set to the 308QV stock specs which are very similar to your 328 stock specs). -1 deg camber would be plenty for street use, and I found the most even rear treadwear at -0.75 deg camber. At the front, I think you could easily try increasing the camber to -0.5 to -1 deg (a camber setting near the low end of the stock 328 spec, i.e., almost no camber, won't help your straight line stabilty). I was running -1.5 deg front camber, and, admittedly, I wasn't powering around sweeping curves at 100+mph, but, for street use, it sure felt great. How are your front wheel bearings? Does the "12 o'clock / 6 o'clock" wiggle test feel good? Your 328 uses a very compact double-row ball bearing that might exhibit more "looseness" with wear than the older, widely-spaced 308 design.
Thanks Steve. I don't believe there's any problems with the bearings, as I had the car checked out recently. I am running 225s up front instead of the 205s, that might affect it. Also, the roads that I'm feeling this most on are _really_ grooved, not in great shape at all.
I have used factory specs on my 89, tire wear has been just fine. The rears (S03's) lasted about 9K including quite a number of track events. The fronts are still going. Remember to have the car properly weighted per specs in manual. You are always going to feel road grooves with manual steering. If you have oversize tires, it will be worse. Dave
I am running a bit of negative camber front and and 2x that value in the rear. This results from a side-effect of my wheels being out-spaced ~11mm in the front and ~24mm in the rear. Only negative side effects I can think of (aside from uneven tire-wear) is that my car now gets very "squirrelly" under hard braking. Steve do you think its a result of the increased negative camber F and R on the tires in conjuction with driving on normal "streets" (ie not perfectly even roads) or the result of something else? I was thinking of getting it reversed to the factory settings to reduce the squirrelliness of the car under hard braking, just never got around to it.
Omar -- Can you clarify your set-up? I can recognize the 328 ABS wheels, but is the car a 328 ABS chassis with the spacer thicknesses you mentioned then added? How large a camber angle is "2X at the rear"? One small negative to increasing the track dimensions of the chassis with wheel spacers is that it moves the contact patch further away from the A-arm mounting points so the fore-aft loads acting on the rubber A-arm bushings during braking are increased -- and the resulting increased deflections from those loads cause the wheels to toe-out more. But please explain what you have -- although I find your description of your personal F enchanting, it really doesn't give any information
Sorry, about that, I changed the wheels to 360 wheels (http://70.85.40.84/~ferrari/forum/showthread.php?t=55962). Direct bolt on, using 360 bolts. The differences in the offset of the 360 wheels F/R is what caused the spacer effect, which as I stated is around 11mm outward in the front and 24mm in the rear (if I recall correctly). After bolting the new wheels I didn't do anything to the alignement, so I guessed that since the rear is spaced out about 2x what the front is the effect on camber would be 2x too. (Not sure if that logic works out)
I don't think it does -- camber is independent of offset (i.e., camber is the same with or without spacers or when using wheels with different offsets).
Really? On every car I have had spacers on, whenever I added spacers the negative camber increased.... On my old E24, I just threw on 12mm spacers and you can literally see the negative camber increase. It was fine before, maybe I was just playing a a visual mind trick on myself.
No, you're probably right in the sense that moving the contact patch outward lowers the effective spring rate so the ride height goes down a little -- which increases the camber on designs like 328 where the Upper A-arm is shorter than the Lower A-arm. I should have constructed my statement to be "at the same ride height the camber is the same".
Interesting, so thats how it works. So do you think that alignment would help my squirmishness under braking or do you feel its the result merely of weak bushings in the front (which exacerbated the sensation)?
I really don't have any experience with your situation to draw on, but I'd be surprised if realigning a small amount would make a big difference (but are you only out a small amount?). Still, I don't see having an excessive amount of negative camber as necessarily a good thing. As I've said in my earlier posts, even tire wear was high on my priority list so I wouldn't want any more at the rear than the stock 328 spec.
You could try adding more rebound to the rear (providing you're not getting entry push). Would help braking/turn-in.
