I added a pair of EMPI shims and it greatly improved the car from wandering. However, it still wanders a little at speeds over 50 MPH. Should I consider adding additional Shims or look elsewhere for solution.
Thanks
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One set of shims only
Check: tires, wheel bearings, pitman arm bolt, steering box, tie rod ends, ball joints.
I'd check caster before I offered a blanket statement on shims. It's possible your frame head was tweaked in a previous life. Check caster, and do a search for how much is enough.
Well, while Alan is technically right, we don’t know what’s been happening to your pan over the years (the front beam, too).
You are trying to get the front caster in the range of 5° - 6° and that’s what the shims do. A single shim adds about 2-1/2° to the front caster, per shim, on top of what was there from the factory.
It’s best to add the shims when the car is undergoing a 4-wheel alignment to make sure you get it right, rather than fudging it at home. The alignment machine will give a digital read-out of realtime caster on both front wheels, so the tech can dial it right in. The tech should use the alignment spec for a 1970 VW sedan and set the front caster to 5°-6°. I usually bring along two sets of shims and a set of longer bolts with me for the first 4-wheel alignment, just in case, ‘cuz these days the techs will never have any spare caster shims kicking around the shop.
Your car may require more than one shim on one side or both. If it does, you will need longer, lower front beam bolts. Both shims and longer bolts are available from CB Performance. ALWAYS use longer bolts if you use more than one shim. You will want to keep the overall caster under 7°, otherwise the steering will be very heavy doing slow-speed maneuvers, like in parking lots. If the tech needs less thickness than a full shim, it’s OK to grind some off the CB shims OR he can use a short length of the right size tubing cut like the CB shim.
Without doing a front end check and an alignment first, you are guessing. You need to check for play everywhere, shoot some grease in the 4 fittings on the beam, then do an alignment. And by alignment, I mean a 4-wheel alignment.
If there is too much toe-out either front or rear, you'll have a twitchy and wandering car.
If this is an older pan based build, ( I have ran into this ) you'll want to check for frame head and axle beam vertical post rust too.
^^^ Yeah, that's a potential big one, especially because the rust/rot can be hidden behind the beam on the vertical supports of the headset (front end of the central tunnel). Good point there, Alan!
@Alan Merklin posted:One set of shims only
Check: tires, wheel bearings, pitman arm bolt, steering box, tie rod ends, ball joints.
And then there was the time I was about to replace my ball joints when I discovered the PO had put the 4.5” wheels on the driver’s side of my car and the 5.5’s on the passenger side.
“Wander” solved. No ball joints needed.
It’s always sumthin with these cars….. 🙄
If the Speedster has been lowered by Select a drop, welding in adjustable center collars, re-indexing the center sections or removing torsion leaves, there will be reduced caster. Even shorter front tires will move the contact patch on the tires forward and aggravate the situation. In extreme cases there could be so little caster that the car could be hard to control even at legal highway speeds and, as Gordon mentioned, could need more than 1 set of shims. Don't forget all the other things people mentioned as well, and as Stan and Danny pointed out, a proper alignment is necessary to tell you where it's at.
A Speedster (or any VW based car) with too little caster is unpredictable at best and just outright dangerous at higher speeds- glad you're going to the trouble of making it right.
@dlearl476- ok, that's really funny! I have to admit I've never seen that...
@dlearl476 posted:And then there was the time I was about to replace my ball joints when I discovered the PO had put the 4.5” wheels on the driver’s side of my car and the 5.5’s on the passenger side.
“Wander” solved. No ball joints needed.
On Spyders, we have staggered wheels AND tire sizes. 4.5" and 5.5" like Dave says, and 185/65/15 and 195/60/15 tires.
Most shops don't even look at them close enough to realize that the different front and rear tires go on the differently sized front and rear rims. They really don't look much different at all.
It happened to me once. I always used to bring the tires off the car along with the balance adapter.
Now I have access to a rim-clamp tire changer and a computer balancer. Doing my own is very satisfying as I've found that if you do it right they're always perfectly balanced the first time.
Recently balanced my 20 inch truck tires. Also mounted and balanced my FV slicks.
@ALB posted:@dlearl476- ok, that's really funny! I have to admit I've never seen that...
One thing I just noticed was missing from Alan’s list: the steering stabilizer. It’s only $20-$30 and a working one makes a lot of difference.
@DannyP posted:On Spyders, we have staggered wheels AND tire sizes. 4.5" and 5.5" like Dave says, and 185/65/15 and 195/60/15 tires.
When I bought my car it had standard VW 165-15’s on it. I’m sure the shop never noticed it like you said. What’s embarrassing is neither did the PO, Carey, or I. 
I only discovered it when I went with Carey’s size recommendations to get rid of the rubbing those tires caused up front.