Nolan Penney wrote:
>
> >My 76 Spitfire has a severe case of positive camber. The top of the tire
> >is leaning out further than the bottom of the tire. Using a level as a
> >rough measure, the top leans out about 3/4" over the bottom. Thats the
> >way the car has been since I bought it (classic auto auction) and I
> >don't know the previous owner..
>
> Just went and studied my engineless 74 parts Spitfire. Even without the
>engine on the
> front, it's only cambered out roughly 1/4" or so. Therefore, I really don't
>think the
> degree of postive camber you've got is due to overstrong/long springs lifting
>the car
> too high..
>
> Since the engine was out, it was easy to really study the suspension and
>mounts.
>
> So what did I see that could hold the top arms out too far?
> 1. If the frame mount is shimed under the engine that would push the upper
>arm out.
> Wouldn't take much of a shim to do this either. Much to my surprise, this
>whole frame
> looking piece is not welded in place, but is bolted on instead..
> 2. Slotted holes where the upper a-arm bolts into the frame mount. They
>aren't
> normally slotted, but if they were modified this could cause problems..
> 3. A-arms that are too long. Don't know of any that would fit and be too
>long, but I
> suppose all things are possible. Didn't measure mine, but I will if you
>want..
> 4. Bent hub assembly. Can't imagine anyone wanting to do this, but if you
>actually
> heated the hub assembly, you could bend it and get positive (or negative)
>camber that
> way..
> 5. Bent frame. It wouldn't be normal to have a frame bent this way, but if
>the
> crossmember up front is bowed up in the middle, or the frame rails don't
>appear
> perfectly flat, that's a good indication..
>
> What could cause the bottom to be tucked in?
> 1. Bent or shortened lower arms. Didn't measure mine. They should be nice
>and
> straight though..
> 2. Trunion installed backwards. The hub assembly should be outside of the
>arm. If it
> was installed backwards, it sure would tuck the bottom in. Though I don't
>see how the
> shock could properly be installed..
> 3. Caved in frame. This is pretty obvious on a visual..
>
> I would also *strongly* advise you to locate another Spitfire to get yours
>beside to
> compare things, hood up. Even a junkyard Spitfire if that's the only way.
>But a side
> by side comparison at this point would be invaluable for you. Let me know if
>there's
> anything I can do to help..
Thanks to all that have replied to my plea for help. I finally got a
chance to get something productive done last night. I added shims
(approx. 3/8") to both left and right lower A-arms and re-adjusted the
gross toe-in (about 7 turns of the tie-rod arms). Now the camber appears
slightly negative and the toe-in is slightly in. I wagged both of these
to get thinks back into the ball park then did a quick road test. Wow!
No more tire squeal and no more hopping around on bumps. It tracks
straight with the steering wheel centred and no pull either way. Just
rolling it by hand in the garage seemed to be much much easier.
I guess the WAG was pretty close. Now I'll proceed to do the final
camber and toe-in adjustments but I'll have to make up the tools for
this. Then the big job will be to find out the real reason for this in
the first place and try to correct it again when driving season is over.
For the benefit all you lurkers and especially to those that have
responded, I'll answer Nolan's point.
Top A-arm
1. Is the tower shimmed under the engine? There was no shim on the left
side and one on the right side. I left the right side in as I wanted to
keep things equal on the A-arm shims.
2. Slotted holes in upper A-arm? I checked for this by loosening
everything up and trying to move the arms in or out. No movement.
3. A-arms too long? This would definitely do it but where would these
come from? These parts were standard for several models, as I
understand.
4. Bend hub? Visual inspection won't uncover this problem unless someone
has bashed the parts (no signs). But I wouldn't expect both sides to be
same positive camber.
5. Bent frame? I'd like to believe this one but my visual of the frame
is that it is straight. There is no sign of bending or damage except
near the tranny where someone has bent the edge of the frame downward
presumably whiel getting the tranny out.
Lower A-arm
1. Bent or short lower A-arms? No sign of bending or damage. As with
upper arms, I don't know of any arms from some other model that would
fit.
2. Trunion installed backwards? I'll have to have a look at this again
but I agree with you that things wouldn't fit together right if someone
tried this.
3. Caved in frame? As per above, no frame damage is evident. The frame
is straight and vertical at the mounting backets as well.
I have done a cursory side-by-side comparison to another Spit of the
same vintage (76 vrs 75). Neither a machanic, an interested by-stander,
nor myself could see any differences visually. We didn't get really
serious and measure things but with this amount of camber you would
expect to see something.
BTW, the camber should be 2-4 degrees positive. Mine must have been 10
plus.
Again, many thanks for your support. I'll keep you posted on what
develops.
Vic Whitmore
76 Spitfire
Thornhill, Ontario
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