Front End Alignment Question

[Gerald C.]

I have attached four pictures of my Upper control arms on my 1963. As you can see the shock tower is closer to the control arm on one side versus the other. In addition, there are many more shims on the short side. The car was hit in the front, years ago.

Does anyone have any ideas what is going on here and how it can be fixed. Is it as simple as a good alignmnet adjustment?

Thanks,
Jerry

[Duke W.]

Re: Front End Alignment Question

It's possible the accident tweaked the frame a bit, or it may just be production tolerance.

As long as you can get alignment numbers in the proper ballpark and it drives okay, I wouldn't recommend doing anything.

If not, you'll have to find a good frame shop that can measure and has a fixture that they can put the car on to tweak things back into spec.

The 1963 Corvette Shop manual has frame dimensions, and you can probably take some of those yourself to get an idea how far off it is.

Duke

[Timothy B.]

Re: Front End Alignment Question

Gerald,

That's a huge amount of shims on the passenger side and I can only sermise it's required to set camber. Get a level and check the camber (in/out) tilt of the rim with the suspension normalized.

Set the camber to 0* or just slightly positive (top out a 1/8"), by removing the same size and equal amount of shims from both front and back of the control arm. Something may also be bent, there are measurements from different points to ball joint tip to check, info for this is in archives.

[Joe L.]

Re: Front End Alignment Question

I have attached four pictures of my Upper control arms on my 1963. As you can see the shock tower is closer to the control arm on one side versus the other. In addition, there are many more shims on the short side. The car was hit in the front, years ago.

Does anyone have any ideas what is going on here and how it can be fixed. Is it as simple as a good alignmnet adjustment?

Thanks,
Jerry

Jerry-----


If you had not said that the car had been hit in the front end, I would have said your problem is probably rooted in frame damage at some point in the car's life. But, you already know that so, basically, that's the answer to why you're experiencing the problem you have. My experience has been that when a car suffers frame damage, frame repair shops rarely get it repaired exactly right. There are MANY Corvettes running around out there that have experienced frame damage, especially from front end collisions, and have frames that are out-of-spec. You're FAR from being alone in this regard.

I agree with Duke that the best thing to do is just have a competent frame shop check and adjust the alignment without performing any further repair. If the problem can be "adjusted out" with shims, that should get you a good driving car. Personally, I don't think you'll be able to achieve an as-new frame condition no matter how much repair you get into, so why go down that road unless you have to?

[Bill M.]

Re: Front End Alignment Question

Does anyone have any ideas what is going on here and how it can be fixed. Is it as simple as a good alignmnet adjustment?

Thanks,
Jerry

My guess is that the right lower control arm got pushed in and back, and the mega shims on the right upper arm are required to get camber and caster the same on both sides (by pushing the upper arm in and back). It would bother me too, but have to agree that if it can be aligned, leave it be.

[Joe L.]

Re: Front End Alignment Question

My guess is that the right lower control arm got pushed in and back,

Bill-------


...which is exactly what can be expected in a right side frontal collision. And, like I mentioned, there are LOTS of Corvettes out there that experienced this type of damage.

[Larry M.]

Re: Front End Alignment Question

Jerry,

Another solution, used by a shop on my car a number of years ago, was to replace the stock control arm shaft with one that had the bushing ends offset.

Look closely at the 'straight-line' relationship of the control arm shaft to where it passes through the bushing, and you'll see that it's not straight.

I don't know if offset shafts are still available, or if it's possible to get them with varying amounts of offset to compensate for different alignment issues.

Larry

[John H.]

Re: Front End Alignment Question

I don't know if offset shafts are still available, or if it's possible to get them with varying amounts of offset to compensate for different alignment issues.

Larry

Larry -

Moog makes the offset upper control arm shafts.

[Gene M.]

Re: Front End Alignment Question

I would sugest to do a simple tape mesure test. Check the front to rear wheel center line on each side and compare distance values. The greater the difference the more the shorter distance front wheel was moved due to crash.

[John H.]

Re: Front End Alignment Question

I have attached four pictures of my Upper control arms on my 1963. As you can see the shock tower is closer to the control arm on one side versus the other. In addition, there are many more shims on the short side. The car was hit in the front, years ago.

Does anyone have any ideas what is going on here and how it can be fixed. Is it as simple as a good alignmnet adjustment?

Thanks,
Jerry

Jerry -

Do you know what the current alignment readings are? That large stack of shims at the rear of the shaft on the passenger side is probably there to bring the top of the spindle rearward post-damage to get positive caster in spec.

[Larry M.]

Re: Front End Alignment Question

Trust Moog to have the solution to all your suspension needs!

[Terry M.]

Re: Front End Alignment Question

I have had two cars frames straightened -- both were involved in accidents before my ownership. Neither was a Corvette, but both were RWD SLA suspensions, which is the same front suspension as ALL CC2 and newer Corvettes. Both straightenings were successful and the cars went on to live a long life of many miles -- likely more than your Corvette will see. Both jobs were done by the same shop, and that shop has a sterling reputation. If you are in the Chicagoland area I will be happy to recommend them to you.

The point is a bent frame can be straightened, but as Joe L said -- it takes a competent shop to do it properly.

[Bob B.]

Re: Front End Alignment Question

Jerry,

Another solution, used by a shop on my car a number of years ago, was to replace the stock control arm shaft with one that had the bushing ends offset.

Look closely at the 'straight-line' relationship of the control arm shaft to where it passes through the bushing, and you'll see that it's not straight.

I don't know if offset shafts are still available, or if it's possible to get them with varying amounts of offset to compensate for different alignment issues.

Larry

Looking at the pictures Gerarld posted it looks to me if my 70 some year old eyes are not failling me the control arm shaft on both sides look like they are already offset. Oldbaldbirch

[Joe L.]

Re: Front End Alignment Question

Looking at the pictures Gerarld posted it looks to me if my 70 some year old eyes are not failling me the control arm shaft on both sides look like they are already offset. Oldbaldbirch

Bob------


From what I can see of them, they do not appear to be off-set type shafts. Attached is a picture of off-set shafts as manufactured by Moog.

[Joe L.]

Re: Front End Alignment Question

I have had two cars frames straightened -- both were involved in accidents before my ownership. Neither was a Corvette, but both were RWD SLA suspensions, which is the same front suspension as ALL CC2 and newer Corvettes. Both straightenings were successful and the cars went on to live a long life of many miles -- likely more than your Corvette will see. Both jobs were done by the same shop, and that shop has a sterling reputation. If you are in the Chicagoland area I will be happy to recommend them to you.

The point is a bent frame can be straightened, but as Joe L said -- it takes a competent shop to do it properly.

Terry------


Think of it like a piece of wire. Take a straight piece of new wire and bend it sharply. Then, try to straighten the wire so that it is restored to the exact degree of straightness it had prior to the bending. You will find that it's virtually impossible to get it back to its original condition. In fact, in the process of trying to straighten it there will likely be additional bends created making the wire "wavy".

The same thing is true for a frame, except that a frame is much more difficult to restore to its original condition than the wire. That's because there are so many components of a frame that are affected when the original bending (collision) takes place and when the straightening process is applied----straighten one component and another is "knocked out of whack".

Like the wire, though, the frame can be made to be functional. It just can't be made to be like it was to begin with.