Hi all, I have a 68 sprint coupe that I'm in the process of restoring/resto-modding a bit. several months ago I bought new 17 inch aluminum wheels from summit, and Nitto nt555 tires, 255/45-17 on front.
Anyway, I've been having trouble with the front end alignment. On my first pair of front tires (yes, I am now on my second pair of nittos on front. The first pair has already been ruined) after the guys at pfefferle (local tire shop) aligned it, it seemed to have a lot of positive camber. Turns out that was true. The outside edge wore off of both tires very quickly. I took it to my local tire discounters and they realigned it for me. Turned out the guys at pfefferle are idiots.
Now I'm on the second set,realigned by tire discounters, but they're still wearing on the outside edge, and the guys at the tire discounters insist that it's aligned properly.I don't have any reason not to believe them do I?
Has anyone else had a problem like this? Could it have to do with the suspension not being compatible with tires as wide as mine, or is there something I'm missing?
2nd, The original suspensions on these cars were not designed for modern radial tires.
One of major benefits listed for the tubular control arms I bought was that one could dial in enough camber to make radial tires happy.
If you stay with the original control arms and install wide radial tires, the tire shops will always have to compromise in the alignment specs.
2012 Mustang Boss 302 #1918, Competition Orange. FGF replacement 2006 Mustang V6 Pony, Vista Blue. Factory ordered. 2019 BMW X3 (Titled to the wife, but I'm always driving it for her. So I'm claiming it) Old projects, gone but not forgotten: 1967 FB 400, original CA car. After 22 years of work, trashed by the guy who was supposed to paint it. I had to sell it. 1980 Turbo Trans Am 1970 Mustang fastback, 351C 4Bbl, auto 1988 Mustang GT, 5 speed 1983 F-150 4x4, built 302 1994 Chevy K2500 HD 4x4, 454 TBI
A good alignment shop should have no problem doing it right...there's nothing magical about these front ends. I've had mine done twice in the last 15 years and 2 sets of tires and never had any uneven wear problems, 225/60 14's and then 215/60. I think the issue you may be having is with the lower profile side walls are harder on the outside edges of those wider tires.
Agreed, I took mine to a guy who specializes in Rods n classics....he dialed it in beautifully....wear is good, tracks good and no oversteer understeer issues..
If you're running factory arms you might not get more than +4 degrees caster (just tell them as much as possible). The camber shoot for -.5 degrees and toe-in as he specified. GlobalWest sells an offset shaft for stock arms to help add negative camber without a ton of shims.
Hi all, I have a 68 sprint coupe that I'm in the process of restoring/resto-modding a bit. several months ago I bought new 17 inch aluminum wheels from summit, and Nitto nt555 tires, 255/45-17 on front.
Anyway, I've been having trouble with the front end alignment. On my first pair of front tires (yes, I am now on my second pair of nittos on front. The first pair has already been ruined) after the guys at pfefferle (local tire shop) aligned it, it seemed to have a lot of positive camber. Turns out that was true. The outside edge wore off of both tires very quickly. I took it to my local tire discounters and they realigned it for me. Turned out the guys at pfefferle are idiots.
Now I'm on the second set,realigned by tire discounters, but they're still wearing on the outside edge, and the guys at the tire discounters insist that it's aligned properly.I don't have any reason not to believe them do I?
Has anyone else had a problem like this? Could it have to do with the suspension not being compatible with tires as wide as mine, or is there something I'm missing?
Thanks a ton in advance, Matt W.
That’s a 26” tall tire right? You’re castor setting is probably going to be limited by the tire size before anything else. Your tire will rub the outside rear corner of the fender opening. You need to just get it as close as you can to that corner and still turn the wheel without contact there. I like that tall of a tire and that is what I run although not that wide. I’ve gone as far as to shave the head of that corner fender bolt so its not so tall. Also regarding the tire wear, these cars will “drive over” the tire when turning aggressively which will wear that outside part of the tire.
Thanks for all the help guys, these are great suggestions. Hopefully I'll be able to get it aligned correctly this weekend, and not by the guys at tire discounters. hopefully I'll be able to find a good local shop that I can work with a bit to make sure it's right. Then I will finally be able to enjoy my new wheels and tires in all their glory. @quick68bird, I have noticed the "driving over" the sidewall effect that you mentioned before, I hoped lower profile and wider tires would help remedy it. Is there any other way that you know of to help that out? I have been thinking about joining the local SCCA and racing a bit for shits and gigs, but I wouldn't want to excessively wear my tires (more). BTW, I agree, 26 inch tires on the front seems to fill out the wheel wells just perfectly.
@quick68bird, I have noticed the "driving over" the sidewall effect that you mentioned before, I hoped lower profile and wider tires would help remedy it. Is there any other way that you know of to help that out?
On first gens, the wheel/tire gains positive camber during compression (opposite of what is desired).
A few possible ways to correct this:
1. Guldstrand mod 2. Taller upper and lower ball joints 3. Tall spindle (no it does not actually raise the car, just changes the control arm arc).
In addition to what mike said, I personally would consider an upgraded front sway bar. This is on my list of things to do. I understand Addeco makes one and also a rear bar. I need to do research on whats best but it only makes sense that a quality upgrade up front and the additional bar out back would help control body roll and keep that tire contact patch more even.
One thing to consider when buying a new sway bar is the steel it's made from. My first upgrade bar was to an original Z28 bar(didn't know I could get one for a TA). It was about 13/16(IIRC). The next bar was a 1" Addco bar. I'd say the GM bar was as good or better. There are different types of frame mounts that can affect how well one works also. A buddy used to use solid alum mounts instead of the rubber or urethane bushed ones.
Thanks for all the help guys, took it to a different shop that found out I had a couple upper a arm bushings that were worn. Got it all sorted out and it handles like a champ! I already have a nice aftermarket front and rear swaybar, so that's checked off the list. I will be looking into other opportunities to get it handling even better though.
