ricketyray

I'm getting ready to install the VBP Perf. Plus; and I'm noticing a stack of shims on the front passenger side a-arm. There's aprox a 1/2 inch of shims stacked on the bolt... there's only 3-4 threads extending beyond the nut.

Is this normal?
Is it safe?
What can I do to tidy this up?
:skep:

Gordonm

Take a look at your upper and lower control arm bushings. If they have not been replaced chances are this is why the stack of shims. If they are cracked and dry rotted I would suggest that these be done before putting on the suspension kit.

Twin_Turbo

the more shims the more negative they try to set the camber, if there's more shims in the front or rear they are trying to get the caster correct. I'd check the bushings too and afterwards get a good alignment.

ricketyray

"...control arm bushings. ...cracked and dry rotted..." That's them. :D

Can I assume that it didn't come from factory like that (with all of those shims)?


[Modified by ricketyray, 8:03 PM 1/27/2003]

Fevre

Got the same thing on mine. Might have been in accident and had a minor 'adjutment'. My car tracks fine and steers fine so I am unsure why so many shims. Also have some dry rotting too.

norvalwilhelm

Mine is the same way. I have almost 1/2 inch of shims on the back and next to nothing on the front. I run 2.75 degrees of positive caster and needed to add all those shims.
As for having only a few thread past the nut is fine. Weather you have 1 thread or 100 past the nut makes not difference to the holding power of the nut.

ricketyray

This forum is the best collections of well-intentioned, good natured, helpful, humorous, knowledgeable, etc, etc.... human beings anywhere.

:cheers:

BB wowbagger

My passenger side,rear adjustment bolt also have about 1/2 inch of "plates".Very strange :yesnod: :cheers:

ricketyray

I'm going to try new bushings with the new a-arms... If that doesn't fix it, I may move on to more drastic action (?).

I'm not sure what happens when shims loosen or drop, but I assume it isn't good. I just figure the more you got, the more potential points of failure...?

MYBLU71

Same here, I have more on the passenger side than the driver side. I know I have tie rod ends that need replacing as well as ball joints... rubber is dry as the Sahara, too.... Where is that parts catalog again?
:crazy:

Gordonm

I had a pile of shims before I rebuilt it. Now I have about one or two shims just to realign it.

ricketyray

That was going to be my next question...

Where are folks dialing in there caster and camber; and what kind of results, i.e.; tire wear, turn in, top speed/acceleration, etc...

:confused:

SARASOTA SAM

I agree with worn bushings,while you have suspension out best renew top and bottom A-arm bushings and possibly ball joints (polygraphite ones are easy long lasting but a bit noise,er as they do not absorb as much vibes).Also a s/s shim pack would be helpful plus some new retaining bolts/nuts.
Bolts/nuts part#572043 from Corvette Central,Have a look at your Vette Brakes/Products catalog for desirable other parts and #s.its worth spending a few more dollars whilst your tearing down/ upgrading you will be amazed at the difference it makes BUT take care compressing coil springs,use correct tool. Lastly yu,ve checked the A-arms /Frame has not suffered a hit and is bent??
I doubt Quality Control would have passed a stack that thick when checked.

Good Luck and watch them springs

Sarasota Sam :cheers: :iagree:

aussiejohn

Gordonm and Norval,
Thank you for your responses to RicketyRay. My 1974 has about seven shims on the right rear bolt and none on the right front while there is one each on the left bolts. Seems a common alignment set up. I guess I'll have to check out the bushes, now. And I thought I'd done all of the hard and dirty work :banghead: BTW, are any of you guys going to the Birthday Party in June? A bunch of Aussies is organising a tour to Kentucky departing the east coast on June 19 and linking up with the California Caravan on their departure a few days later. I'm hoping to find the money to join them and see some of you guys in the flesh ( well, some of it anyway! ) .

:party: :cheers: :cheers: :cheers:

Regards from Down Under

aussiejohn

gkull

I have the max amount of castor that stock A-Arms can handle without going beyond the nuts capacity to hold them. 3.95 degrees of castor Zero toe and right now 1.14 neg. camber.

New Moog ball joints make a world of difference if yours are over 10 years old.

ricketyray

I was wondering how the car would track at high speeds with zero toe...

this was the recomendation for the C4;

Daily driver:
Front: Toe-in 1/32 inch
Camber 0 degrees negative
Caster 5-7 degrees positive
Rear: Toe-in 1/8-inch
Camber 0 degrees negative

Advanced Street:
Front: Toe 0”
Camber .25 degrees negative
Caster 5-7 degrees. pos.
Rear: Toe-in 1/8 inch
Camber .50 degrees negative

Autocross:
Front: Toe-out 3/16 inch
Camber 2-1.5 degrees negative
Caster 4-5 degrees positive
Rear: Toe-in 1/16-inch
Camber .75-1.5 degrees negative

Track:
Front: Toe-out 0”-1/16”
Camber 2-1 degrees negative
Caster ???? (probably 5 or more pos. if you can get it)
Rear: Toe-in 1/8”
Camber .75-1.5 degrees negative

:steering:


[Modified by ricketyray, 4:16 PM 1/28/2003]


[Modified by ricketyray, 4:20 PM 1/28/2003]

gkull

Vette Brakes and Products give base line setting for C-3's I would not use a C-4 as a base line setting.

I normally run Zero toe front and rear and .60 neg front camber and .50 or less neg rear depending on what I'm doing.

Zero toe helps your car go where you point it. I wouldn't have it any other way. I've put on over 100,000 miles with those type settings

The major draw back to high speeds in my Vette or for that matter most any car is too quick of steering ratio. It's very difficult to maintain a straght line on a low adheasion surface at over 175 mph.

to tell you the truth. I don't feel safe in a stock C-3 corvette. They are not a touring car at all. I'll take part of that back. When our Vette's were brand new with the upgrade performance suspension package they were probably on the top of all American cars in the handling department. I thought that my 78 & 79 were real corner carvers. Just lacking power. But as the years go by they just get more and more slop.

ricketyray

My theory was that the VBP Performance plus would have handling chacteristics closer to a C4... But I've never been in a car with the VBP P+ package so I'm no authority...

I'm beting if you did the hwy 318 (or hwy 278?) challenge event :D you know a little something about the handling characteristics C3's when pushed hard. :yesnod:

Mack

Sam pointed out something above that I want to reinterate. Be aware that bent frames are sometimes compensated for by using large numbers of shims. I'm not saying this is the case here, but it's something you should know.

ricketyray

Mack76 & Sam, I was going to take a closer look when I got home... as it stands the body is off the frame and I looked them both over for any signs of collision, and nothing jumped out at me. But it probably warrants a second more careful look. I can say that bushings, etc... look like they've had no attention in it's 30 year 80K mile history. Let's hope that's all it is.