Bump steer/Rack and pinion

[NixVegaGT]

WOW thanks Scott. That really does answer some issues I remember from when I was driving my car around. One thing I always noticed is that the car would really skip on concrete clover leaf's. Every time it went over the expansion strip it would skip. I'm certain now that it was the neg. ackerman that was making that so apparent.

[Ishiftem]

Scott, I just need a measurement from the lower front control arm bolt(center) to the ground and what tire size you have. I have my own car to measure for everything else. My shop manual has the ride height, but it what the diagram shows and what the text says is two different things. Makes no sense. The parts do have to be on the car for the most part. It's how the measurements are taken in relation to the chassis. Its kind of a some do some don't kind of thing.

[NixVegaGT]

I'll make a general call. Maybe with a bunch of input we can get a decent mean.

viewtopic.php?f=1&t=28641

[Astre-mutt]

I like to change something I stated earlier about the measurements I took of the Ackerman. I stated that the Ackerman was out 4' 4". That was wrong! It is the 25" measurement that is correct. It's still a bunch, but not no 4 feet.

[waybad]

I was searching and found this,, look how the tie rods bolt to the rack,, I think we could move the mounting holes and get the proper length tie rods to have better bump steer??? just a thought,,
http://www.flamingriver.com/index.cfm/p ... prd361.htm

[NixVegaGT]

I like it. Not so into the hanging down part but it could be made of something less obtrusive. May help the guys who have more standard rack ends.

[NixVegaGT]

This is a pretty great pic of the suspension geometry from another thread. Look at how much ackerman the stock tie rods have but I also noticed that they look like they end at right angles to the steering arms. Interesting. Is this helpful?

[waybad]

by putting a rack in our cars and moving the rack toward to the front,, it will straiten out that angle?

[Ishiftem]

There is more going on than that. I'm having trouble getting my new software to work with vista. I'm working on it though and waiting to hear back with a solution. If microsoft built cars, you would have to open and close the windows before you could start it.

[SunbirdMan]

.. If microsoft built cars, you would have to open and close the windows before you could start it...

If microsoft built cars they would all be recalled.

[Astre-mutt]

If microsoft built cars, you would have to open and close the windows before you could start it.

Windows ...... I get it!

[grandam75]

This is very interesting, I would really like to change the mounting points for the outer tie rods to get faster steering and fix bump steer. I was in a hurry when ordering parts for my vega. If I had done some research before I would probably have used AFX spindles with the bolt on steering arms. Have anyone compared measurements of the AFX spindles and S10?

[NixVegaGT]

I've seen some references to the AFX spindles being used in S10s They must have the right BJ tapers for that. I've also seen some references to the UBJ mount being higher by an 1.5" or so. That would go a long way to help the camber gain. Not cheap parts but the look really light. They use C5 calipers too? Hmmm. I gotta stick with my plan for the short term but that looks like a good way to go.

[Kenova]

Have anyone compared measurements of the AFX spindles and S10?

http://store.nexternal.com/shared/Store ... =545570015
The 'Vette brakes require 17" wheels but there is (was) one company making a brake kit that would accept 15" wheels.

These may also be of interest. I doubt they would work on our cars but they do make one think ......
http://store.nexternal.com/shared/Store ... =545570015

These are new to the market and accept any brake kit for the early F-body spindle. They are also available without the 2" drop.
http://www.lhkustoms.com/products.htm

Ken

[Astre-mutt]

Ken, that is nice stuff, but over my budget. Maybe some day.

I was thinking about the effects of ackerman on the car when turning. It dawned on me that ackerman is for a controlled turn, and that ackerman my have a negative effect in a power slide. This made me think of something Marco said about his Spyder. He stated that when he hanged the back end out in a slide, the car was very easy to drive. I figure it is because a power slide is not a turn. You get an advantage of having both front tires turned in the direction of the slide. With zero ackerman both tires are facing the same angle, so it lets you steer into the slide with more control.

This doesn't change my planes to modify my steering arms to acheive proper ackerman. Because I'm trying to improve the cornering ability of my car in controlled turns. Not improve the handling in uncontrolled turns (aka power slides), but it maid me think there is a use for zero ackerman. That would be Drag racing. Zero ackerman (which is what the stock steering arms have now) would be a definite benefit tyring to save a out of control Drag car. Lets face it, running narrow tires doesn't give you the best handling anyways. So adding ackerman would benefit a Drag style car on the street in every day driving, but probably hurt handling when trying to get a car back under control. Which could be the difference between wrecking your car, or not.

Putting a rack on a Drag car with the proper length (22") would improve handling by eliminating Bump Steer with the stock spindles, or S10 spindles. I don't think there would be any benefit from adding ackerman. I did find that Flaming River makes Mustang II racks in shortened 2" 3" & 4" lengths. The 2" narrower rack will give you the 22" you will need for stock spindles. It will cost you about $275 over stock length rack, but be the right size. http://cgi.ebay.com/ebaymotors/FLAMING- ... 20ac1bb159