TR2/3/3A TR3 alloy wheels and Front suspension upgrades

[karls59tr]

Hello TR enthusiasts. First time on the forum. I picked up a nice set of Shelby Cal 500 slot wheels on Ebay that I think will look great on my "3". They are 5.5" wide so better traction and stability I'm assuming? The tires are 185/65X15 so fender clearance shouldnt be an issue. I'm going to change out the trunnions and get a front end alignment. Does anyone know if I will have to alter the camber/castor by installing the new wheel/tire set up? The offset of the alloy wheels is 6mm and I think I will have to add 6mm spacers to clear the front brake calipers. Classic Motorsports Nov. issue had an article on 3 front end mods: ie replace upper A arms with TR6 ones and TR6 ball joints.(you can also swap in XJ6 balljoints) Would it be necessary to use TR6 trunnions or could I stay with the TR3 ones I just bought? The article wasnt clear on whether the lower A arms should be switched to TR6 as well. I'm not going full bore racing just Sunday autocrossing. Anybody upgraded their TR3 front suspension and gone to larger wheels? Any advice and input greatly appreciated. Cheers Karl

 

[AltaKnight]

Hi Karl.....
Welcome aboard the forum.
I can't answer your questions since I'm not familiar with the suspension mounting on the TR3; I would expect that someone is familiar on the forum can answer.
Anyway, good luck, it's great to see another Canuck on the forum.

 

[martx-5]

The TR3 front suspension unfortunately has only one adjustment...toe-in. If you want some caster, there is the trunnion that Triumph started to use in early TR4 production, somewhere around CT6400. This is a 3 deg castor. I don't know if you have to put in the later TR4 or TR6 upper A-arms to go with that. I would assume so. The Jag ball joints are a little thinner then the TR units, so you can shift the center of the joint back farther. The other advantage of the TR6 A-arm and ball joint assembly is that you can slot out the ball joint mounting holes in the A-arm a bit to introduce some negative camber. How much to slot, I don't know. Then after you get the negative camber worked out, it would be wise to to weld up the outer part of the slots or weld washers on the outer part of the A-arm where the bolts go through so the settings don't move.

The other alternative for camber adjustment is to get the adjustable upper A-arm kit from Revington TR.

 

[karls59tr]

Thanks for the info Art. Most appreciated. Karl

 

[TRTEL]

Hi Karl, There's a great deal more to consider in doing the switch to the castor set up. If you decide to do that at the minimum then you'll need TR4 trunnions with the 3 degrees engineered in. Then you'll still be able to use your vertical link and your TR3 lower A arms. That set up does change the position of the steering arms somewhat, but there's not much you can do about it, because even if you have access to early TR4 steering arms they don't work with the TR3 tie rod ends. Making the switch to 4A/250/6 parts is even more problematic, although great for competition purposes, as it lowers the front end almost two inches (read less practical for the street). Suffice to say that to get things to work at the very least you have to have a very large spacer, preferably of aluminum, for the top of the spring tower to mount the upper A arms to. If this doesn't chase you off send me an email and I'll give you the rest of the bad news.

Tom Lains
TS8651 & 58107

 

[karls59tr]

Hi Tom I'm starting to see that there is a lot more to it than I thought at first. Do you see any problems with just running the stock 3 front end suspension configuration with the alloy wheels and tires I mentioned for use as a daily driver? Karl

 

[PeterK]

We run minator 15x5.5 w/205/60-15 tires on our 58 TR3A, a slight tire to fender rub in the front at full lock standing still. We used 3mm rear spacers to keep inner rub when hanging out the rear end. For normal driving (what's that?), no rubing.

 

[karls59tr]

Hi Peter Did you have to alter the front suspension to run that wheel/tire set up? Are the hubs strong enough... I've heard of them breaking back in the day when TR6 wheels were used on the 3? Karl

 

[TRTEL]

Karl, I've used 185's of various profiles for years on 5.5" alloys without problems, but as Peter pointed out above that you may want to be a bit more cautious.

Tom Lains
TS8651 & 58107

 

[PeterK]

nope, just bolted them on, no problems.

 

[YankeeTR]

Anything can break but I would think that running a larger wheel/tire combo won't be a problem during NORMAL driving..

I test drove a TR3A with TR250 wheels and 195/70's and they worked great. The owner had them on the car for 12 years with no problems.

 

[karls59tr]

Well thats encouraging to hear. I guess I've been reading too many articles about full out racing where every car component has to be top notch and reinforced to take the stress. I cant afford to go racing so I'm basically making the 3 reliable mechanically and upgrading to make the car perform and handle better with the possible option of doing some Sunday autocrossing. The upgrades I've done so far are:rebuilt the motor(broken crank...still driveable but sounding like the hammers of Thor.);put a header on (having second thoughts about that....really loud but I like to hear the engine at full song);mild street cam(more grunt);electric fan;roll bar(you never know...although it ruins the lines of the car). Wouldnt mind some Brooklands screens. Cheers Karl

 

[PeterK]

After adding the rollbar, we really liked the new look. We overheard people at this show saying that the bar didn't detract from the lines and liked it. We agree. Decide for yourself.

 

[karls59tr]

No the roll bar looks allright,,,,,very purposefull. Is that a "sticks cover " or a full tonneau cover you have? It looks like its been slightly altered to accomodate the roll bar. My roll bar is similar to yours. I was wondering how I was going to use my tonneau. It appears that you've found a solution. How was that done? Karl PS.Great looking 3.

 

[PeterK]

It's a full tonneau that I had altered at an upholstery shop. It's not watertight anymore but we rarely see rain in it anyway.