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DougF
11-19-2006, 09:00 PM
Has anyone else experienced negative camber problems in the front end of their TR6 after installing Good springs?
When I contacted Richard about it, I never received a response.
I have people comment on how sporty it looks. I don't mind the look, but do mind the short tire life.
I've made some adjustments, including the removal of the shims. It's not as bad as it first was, but I'm still looking at less than 10,000 miles on front tires.
There is no evidence of frame or suspension damage.

LastDeadLast
11-19-2006, 10:05 PM
I can't recall what it's called, but that little metal thingy that you bolt the upper suspension arms to can be reversed to give you a degree or so of extra camber.

I've also got the Goodparts springs and my suspension lined up nicely without and shims.

Keep us updated on your progress.

crj7driver
11-19-2006, 10:07 PM
When I installed my "race" springs from Moss it lowered the car about 1 inch and did induce a bit more negative camber. I had the front suspension adjusted a bit, but it still sits on the negative side. FWIW I am still on the same set of tires 5-6 years later with no excessive wear.

DougF
11-19-2006, 10:11 PM
Thanks. That's one of the adjustments I tried. But I will look at it again. I've also gone so far as to put shims between the shock towers and the cross member. I did get results from the shims, but I don't like stressing the frame.
Huh! I just ran out and looked at the fulcrum pins(I had to look up the name). One is adjusted and the other is normal.
Must have had too many of my favorite beverage that day! I will have a project for tomorrow evening. Thanks!

Alan_Myers
11-20-2006, 04:22 PM
Hi Doug,

I'm not experienced with the Goodparts springs in particular, but might be able to contribute a few suggestions about general front suspension setup...

Have you had the car professionally aligned? With the various changes you've made, I think it would be a good idea to do so.

Often alignment shops refer to a catalogue of OEM specifications, though, so you'll probably need to give them some guidance what you are looking for.

For a street car, around 1/2 to 3/4 degree of neg camber is not uncommon with modern radial tires. Even a full degree isn't unreasonable, IMHO, although it will likely make the steering a little heavy at lower speeds. Much over 1 deg neg is getting into more radical race settings and probably will cause faster tire wear like you describe, although the car will go around corners like it's on rails!

Toe is also very important, should be about 0 to 1/16" toe-in with modern radial tires. On a street car, that's probably the more critical adjustment in terms of tire wear. But, a lot of neg camber combined with a lot of toe-in or toe-out might cause really rapid tire wear.

The other adjustment is caster, which is about 2.75 to 3 degrees typically on TRs (after the first 6000 or so TR4s, which had 0 caster, like all TR2/3).

Also, I don't think you need to be too concerned about having adjusted it a bit by shimming the top cross member. That's an acceptable way to "tweak" the front suspension of TRs: shortening the cross tube to induce more neg camber, shimming or lengthening it to move it more positive. The only problem with using this method to make the adjustment is that there is no way to precisely adjust each side individually. It will simply pull the shock towers together or push them apart (along with the upper/inner fulcrum mounting points), and might do so unevenly. However, with the other available adjustments on your car, it should be possible to dial in each side more precisely, after making coarser adjustments with the cross member and upper fulcrum orientation.

Also don't overlook the rear alignment, since that can effect front tire wear, as well. Other factors that can cause faster wear include sway bar setup and un-balanced (front-to-rear) braking.

Finally, some tires simply wear rapidly, due to softer compounds and some other desgin factors. I had a couple cars in years past that used Pirelli P6 tires, which are great for cornering, but only lasted about 20K miles (or less if driven hard). Those tires had particularly stiff sidewalls that prevented much tire roll, but made for a coarser ride and a lot faster treadwear.

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DougF
11-20-2006, 05:49 PM
I am currently running Kumho tires from which I am getting about twice the wear from the rears.
I aligned the tires myself. I used the same method for my TR3 and then took it to a shop. It was within spec. The TR6 tracks very well. I've held off on a professional job because of ground clearance onto the rack.
After I was thinking further about the fulcrum pin, I recalled switching one side and it didn't result in much movement so I held off on switching the other.
BTW, the car does handle as though on rails.

11-20-2006, 06:04 PM
Doug, I feel that you really should seek the help of a professional alignment shop, one that understands old cars. Meaning, many shops today do by the book and don't understand the true mechanics of alignment. My current TR6 ate up a set of Pirellis in 6000 miles (that said, Pirellis are not know for high mileage anyway), till I had it aligned by an old hand that knew what he was doing. I have shorter springs front and rear, and kept the fulcrum pin in the original position. The old alignment guy was even able to swap out shims on my rear swing arms and gave me perfect alignment. I currently have Michelin Hydroedge tires with 12000 miles on them and see no appreciable wear.
Get a professional alignment done.

Alan_Myers
11-21-2006, 03:39 PM
[ QUOTE ]
Get a professional alignment done.

[/ QUOTE ]

Bingo! (4 wheel alignment, preferably)

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