For everyone who has done the B-body conversion and wondered about bump steer. There is a good article in the April issue of "Speedway Illustrated" I've seen the discussions here with the pros and cons of the B-body brakes vs. stock. I haven't noticed any problem after doing mine but some say they have. This article goes into what it is, how to check it and how to fix it. I figure some of you might be interested.

Jeff

Good spot Jeff. If anyone else wants to read about this I have two old Circle Track articles that discuss Bump Steer. I could scan them in an e-mail them if anyone is interested.

airrj....would love to read them as I know very little about front suspension geometry. Thanks...John

i would love to read that. both of yours.

I will try to did it out tonight and scan it tomorrow. If you don't hear from me by Friday give me a cyber kick in the head graemlins/clonk.gif

Originally posted by airrj:
If you don't hear from me by Friday give me a cyber kick in the head graemlins/clonk.gif Send me a copy too :D

I'm always game for a chance to graemlins/clonk.gif ;)

Joe

Bottom line, last word, bump steer = bad

Originally posted by Slo307:
Bottom line, last word, bump steer = bad Weeeeelllll, like anything, it isn't ALL bad. Too much can be bad, but the right amount and the right kind can be good.
For instance, most circle track racers who race short tracks will tell you that you want a little bit of compression toe out to get the car to turn in quicker when you get on the brakes if the turns at the track are tight like at the old Saugus Speedway. Roadracers on the other hand would want a bit of toe in on compression to stabilize the car when you hit the brakes (for instance, turn 1 at Willow Springs, you would be getting to the braking point in a big car at around 140 or so. You certainly don't want the front end twitching around when you hit the whoa pedal before turn in.

Just a couple of examples from my experience.

K

Problem is that the tall spindle toes out which is alway very very very bad, yes it can be fix with a bump steer kit like that available from Baer. The other problem can not be fixed that easy, the ackermann princple is still wrong, new steering arms would be required, which can't be done because of the tall spindle steering arm design.

Originally posted by Q-ship:
toes out which is alway very very very bad. Q-ship,

I must disagree with you on this point. Toe out on compression will reduce the steering angle on the outside tire as it compresses. This will cause an understeer and for a street driven vehicle understeer is safer than oversteer. With Joe Q. Public driving in an understeer condition Joe will lift off of the gas and the car will slow and the understeer will correct it self. With Joe in an oversteer condition, Joe will be backwards, upside down, or in the trees before he knows what has happened.

I am not debating the merits of tall vs. stock spindle bump steer, but stock spindles also toe out on compression. About half as much as the tall, but they do toe out.

FYI Joe, Pete, and John you should have mail. graemlins/thumbsup.gif Jeff did you want a copy?

Originally posted by airrj:


FYI Joe, Pete, and John you should have mail. graemlins/thumbsup.gif Jeff did you want a copy? Thanks RJ! graemlins/thumbsup.gif graemlins/beers.gif

Think my control systems professor will wonder why I'm reading articles on bumpsteer instead of bode polts? :rolleyes:

Joe

Originally posted by airrj:
FYI Joe, Pete, and John you should have mail. graemlins/thumbsup.gif Jeff did you want a copy? [/QB]If it's not too much trouble, sure, I'd like a copy. There probably will be new theories by the time I get around to doing anything about it. I have to build a garage first! :D