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Is the Weltmeister Bump Steer Kit Sufficient?

The one that Pelican sells--does it suffice for SC/Carreras lowered to 25" FR, 24.5" RE? About 1/2" overall. Is more/less spacer needed?
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Old 12-12-2002, 03:39 PM
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I put in on my '84 Carrera which was about 24 1/2" and it worked wonders. For $15 you can't go wrong.

JG
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Old 12-12-2002, 03:44 PM
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kristian85,
The spacers are a quick and dirty method of approximating bump steer correction on a lowered car. So yes, do install them.

You may not want to know the "correct" method as it takes some jigs and dial indicators and then some way to adjust it. It's detailed in Fred Puhn's book, "How to Make Your Car Handle" as well as several other books on chassis design and race car setup.

Using ERP tie rod end adapters is one method to correct bump steer (a steering/suspension factor, not a ride sensation), but you still have to go through the setup and measuring procedure.

Sherwood Lee
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Old 12-12-2002, 03:52 PM
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24.0" rear 24.5 Front and not a problem. Drives perfect.
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Old 12-12-2002, 04:31 PM
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I've got a Weltmeister kit too. Works fine.
Old 12-14-2002, 01:39 AM
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Two 10 x 65 hex bolts (8.8) and 2 x 16mm stainless steel nuts are all you need to adjust the steering rack. Use the 16mm SS nuts as spacers, they are 12mm thick, never rust. Back off the shaft union bolt, lift up rack, insert 16mm nuts and tension 10mm bolts; easy. cost? around $5.00 from a good bolt supplier.
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Old 12-14-2002, 04:09 AM
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My '86 is running at 24.5f/25r and I didn't find the bump steer kit necessary. (I have one, just never used it.) I'm running stiffer torsion bars so that may limit the amount of travel and resulting bump steer. I've heard they may cause the steering linkage to bind.
-Chris
Old 12-14-2002, 04:41 AM
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Cool

Before you lift up the rack, consider going into the 'smugglers box' and loosen the U-joint connection on one side so you can push up the rack without putting pressure on the steering column bushing. I run 25F/24.5R with a 12mm spacer and it feels fine.
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Old 12-14-2002, 01:53 PM
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Just to throw the alternative in the mix, I went with the Smart Racing drop link bump steer kit. Worth every penny IHMO. The car is a little lower than 24.5 in the front but the drop link is necessary for the 1" adjustment that was necessary on mine. Like others said, you can't go wrong with the $15.00 kit. If it doesn't work, then move to the more $$ type.
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Old 12-14-2002, 02:45 PM
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Exclamation

I had mentioned backing off the bolt on the universal jiont on steering shaft.
Lowering front also effects turning circle as lenghts of tie rods are effectively shorten. Raising the rack restores tie rod angle and lenght, thereby reducing turn circle.
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Old 12-15-2002, 12:14 AM
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Quote:
Originally posted by peter915
I had mentioned backing off the bolt on the universal jiont on steering shaft.
Lowering front also effects turning circle as lenghts of tie rods are effectively shorten. Raising the rack restores tie rod angle and lenght, thereby reducing turn circle.
I don't follow. (Effectively) shortening the tie rods would only change the toe, not the turning radius.
-Chris
Old 12-15-2002, 05:06 AM
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Peter

Quote:
Originally posted by peter915
..........Raising the rack restores tie rod angle and lenght, thereby reducing turn circle........
huh??
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Old 12-15-2002, 06:16 AM
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Thumbs up

Imagine a right angle triangle upside down, with the R.angle at top.
Right angle is at the centre of vehicle, with wheel centre out on the end of triangle. (horizontal line from wheel centre to Right angle).
The angle line from wheel centre down to bottom of triangle is the angle the tie rod makes when car is lowered. The length of this line as we know ( trigonometry)(3,4,5) is shorter than the
horizontal line.
The horizontal line is where the rack was/should be. With the rack in the bottom postion (triangle), the tie rod is shortened and therefore cannot push the wheel out as far as it would if rack where higher. This causes a larger turn circle, which was how my 3.2 was (thanks to previous owner).
Ok, I didn't use special tools or gauges to check all this, but I do know what a differance this has made.
Hope thats clear,
Peter
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Old 12-15-2002, 09:19 AM
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Rothsport in Portland Oregon owned by Jeff Gamroth who is Alex Jobs crew chief on the #23 car ( in his other life) installed a spacer ( ? mfg. ) under my steering box when the car was up there for a suspension tune up.

If Jeff and crew use them, then they must be OK. No half a$$ from that shop, ever. They maintain and build some very fast race cars. You should see the 3.8 Euro spec. 1973 911 Hot Rod they built last spring, sectioned the rear trailing arms and moved the brake position so they could mount 9x15 Fuchs in the rear.
They are also not cheap, but the best in Portland for suspension work.

If I lived in the Seattle area I would go see Greg Fordhal (spelling) he is the King in your area.

Randy Jones
1971 911 "Iris"

Last edited by RLJ; 12-15-2002 at 10:18 AM..
Old 12-15-2002, 10:13 AM
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Quote:
Originally posted by peter915
Imagine a right angle triangle upside down, with the R.angle at top.
Right angle is at the centre of vehicle, with wheel centre out on the end of triangle. (horizontal line from wheel centre to Right angle).
The angle line from wheel centre down to bottom of triangle is the angle the tie rod makes when car is lowered. The length of this line as we know ( trigonometry)(3,4,5) is shorter than the
horizontal line.
The horizontal line is where the rack was/should be. With the rack in the bottom postion (triangle), the tie rod is shortened and therefore cannot push the wheel out as far as it would if rack where higher. This causes a larger turn circle, which was how my 3.2 was (thanks to previous owner).
Ok, I didn't use special tools or gauges to check all this, but I do know what a differance this has made.
Hope thats clear,
Peter
Peter,
The tie rods are length adjustable so any length change would only there until you got it aligned. When you lower the car the tie rods are, like you said, effectively shortened. The tie rods run behind the axis of the wheel so this has the effect of pulling the trailing edge of the tire in (and the front out) causing toe out. I kinda doubt that changing the toe will effect the turning radius. Toe out would allow the inside wheel in a corner to turn more sharply and the outside wheel to turn less.
Lowering also changes the camber and the castor. These suspension changes are the reason that lowering, aligning and cornerweighting are often performed at the same time.
-Chris
Old 12-15-2002, 11:07 AM
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Angry

Chris,
As Wayne D points out in his book "101 projects", the lowered rack makes bump steer worse. This happens because the rack is now below the centre line (axle) and any bump pushing the wheel up causes the tie rod to pull up on the rack; hence the effect on the steering (bump steer).
And yes, do a wheel alignment.
Peter.
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Old 12-15-2002, 12:57 PM
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Quote:
Originally posted by ChrisBennet
Peter,
The tie rods are length adjustable so any length change would only there until you got it aligned. When you lower the car the tie rods are, like you said, effectively shortened. The tie rods run behind the axis of the wheel so this has the effect of pulling the trailing edge of the tire in (and the front out) causing toe out. I kinda doubt that changing the toe will effect the turning radius. Toe out would allow the inside wheel in a corner to turn more sharply and the outside wheel to turn less.
Lowering also changes the camber and the castor. These suspension changes are the reason that lowering, aligning and cornerweighting are often performed at the same time.
-Chris
I was going to post a descriptive reply but thanks to Chris being on the money I saved myself some keyboard work

Kurt Williams
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Old 12-15-2002, 01:28 PM
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Quote:
Originally posted by peter915
Chris,
As Wayne D points out in his book "101 projects", the lowered rack makes bump steer worse. This happens because the rack is now below the centre line (axle) and any bump pushing the wheel up causes the tie rod to pull up on the rack; hence the effect on the steering (bump steer).
And yes, do a wheel alignment.
Peter.
I agree 100%.
Chris
Old 12-15-2002, 03:37 PM
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