I have a couple of questions regarding my '71. I installed a refurbished trailing arm because the previous one had bad bearing and looked a little bent. After having done all the adjustments as toe in, tracking and camber I realised that the tire on the new arm is not as far out as the opposite tire. On the driver side the tire is actually outside the fender and on the new one it is inside. I am missing about 1,5” on the new arm compared with the old one and the opposite side. The half shafts fits correctly on both sides. The old and the new arm looked alike. I had to adjust a lot to get the camber.

I know that there are some special arms that extend the wheels but I do not have this type on my car. Any ideas what can be wrong here?

The other problem is the vacuum. The headlight doors open up when i start the car and the vacuum builds up and then closes again. The viper door opens when vacuum disapears after having shut down the engine. As long as vacuum is present everything works fine. All valves and hoses are new and correctly installed as I see it. I assume that the vacuum eventually will disappear after a while when ingine is not running or am I wrong? Any ideas how to correct?
Henry

 

1) Not correct. The trailing arms you refer to simply give more clearance for wide tires. They do not move the wheel mounting flange position one way or the other. The same idea applies to your new stock trailing arm. The wheel position is determined by the length of the half shaft, plus the length of the wheel spindle and bearing ***'y. Compare your old to new there should be no difference.

2) The hoses are usually not the problem, but people like to blame them. There's lots of information in the archives. Get one of the troubleshooting guides to determine which components are leaking.

 

Look at the shims on your old trailing arm. Mine had an equal number and equal sizes on the outside and on the inside resulting in the trailing arm being centered in the mounting bracket.

Your left trailing arm may also be bent.

Your left rim may have a different offset than the one on the other side.

You did not mention if the right wheel stuck out of the wheel well before you replaced the trailing arm.

When you say you had to adjust a lot to get the camber, exactly what adjusting did you do?

The camber is set with the eccentric bolts on the strut rods. There really isn't that much adjustment to them.

Also, are your strut rods straight or bent? Some alignment techs bent them to set the camber instead of using the eccentric bolts. Other times they got in the way of a floor jack and ended up bent.

cc

 

was the old arm the off-set style?

 

I was wondering the same thing. Maybe a PO replaced them with off-set arms (that appear to be bent) for some wheels/tires that he/she wanted to use.

 

NOPE

Offset T-Arms do not move the location of the wheel bearing. They are just shaped differently to allow greater offset wheels.

 

Test the check valve in the line from the manifold.

 

Thanks for your feedback. The new and old T-arm is measured and are identical. Half shafts are same lenght on both sides. No bent strut rod. Strut rod is without the eccentric bolts, it is adjusted by turning the rod inn or out on threads.
I can not recall that I had any difference on the sides before, I would have noticed it I would think.

I think that I need to start over with all adjustments.

I only moved the car forth and back in the garage. Maybe things need to come into place after a short drive.
Regarding the chamber I adjusted the strut rod to achieve a 1/2 degree or so inwards on the top.

Nothing has really changed except for new rotors (they are same thickness both sides). No offset arms.

So I think proper adjustment and taking the car for a ride might be solution to move the stuff a little bit?

 

You definitely need to go for a "shake-down" cruise to settle all the components into their final position. Then, you need to tweak the adjustments in or [better yet] take it to an alignment shop to get the rear wheels set properly.

 

Regarding the difference on the rear stick out of the wheels I have found out that everything is ok from the differential and out meaning that there is nothing wrong with the stack up of parts. What I have found out is that measuring from the wheel well and in to the main frame there is about 1 inch difference. This means that the body may be installed offset. Is this possible and if so is it an easy fix or should I just leave it.

Regarding the vacuum where the headlight doors opens at startup and then closes and the wiper door opening I could not find anything (yet) in previous posts. What I have found out is the following. The entire vacuum system is not holding pressure after shut down over a long time. The wiper door opens when the vacuum reaches a certain value. When this happens the vacuum to the actuator relay dissapear and the spring pushes the relay to open door position. At this point there is still vacuum left to actually open the door and it stays open. Then at next startup the door closes again and at shut down it happens again, door opens when vacuum disapear.
I guess it is the same thing with the headlights. When there is no vaccum in the system at startup the headlamp relay is in the door open position due to having no vacuum to the relay and the spring positions the valve to open position. When I start the car vacuum builds up and the doors opens before the vacuum to the actuator is strong enough to pull the valve to the close position. Therefore the door opens and then closes again.
Am I wrong with my thoughts here? Do anyone have a fix on this? I think that if the vacuum would be 100% leak free this would not happen because vacuum would stay on forever, but is it realistiv to have such a tight system?

 

Once you had a car up in the air and set it down it take wahile for things to settle in. You really need to drive it a few miles and then evaluate the positioning of the wheels. It sounds like you should have the alignemt checked. Remember, these are not precision built cars, It wouldnt surprise me if there's difference from left to right.

 

Sounds like sticky relays. Good luck, new relays have been known to be sticky. I think www.corvette-101.com has a very good faq page on how to diagnos the enite system. All you need is vacuum pump. Follow the instructions step by step and you'll be good to go.