Thread: Rack & Pinion measurements?

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Abusive?? O.K., I guess I'm guilty as charged. I probably was having a bad day or was tired of fielding newbie questions. I guess I was taken aback that someone would start a project like this and not have all the geometry worked out beforehand.

Don, it's not rocket science, but it is geometry and it must be pretty much spot-on to make the car handle and steer correctly.

On my last project car, a scratch-built frame and IFS under a T, I read every suspension book and booklet I could find. None of it made sense in the respect that nobody seemed able to offer up an answer on designing the whole IFS from scratch. Finally, I stumbled on a set of books authored by Carroll Smith and voila!!, it all fell together for me. The very talented Mr. Smith was the crew chief for Ford Motor Co. when they whipped Ferrari at LeMans with the GT40. If you haven't read Prepare to Win and Tune to Win, drop your wrenches and grab your credit card....
http://www.amazon.com/exec/obidos/tg...books&n=507846
http://www.amazon.com/exec/obidos/tg...books&n=507846

I believe it is in the back of Tune to Win that he explains how to set up your suspension with "paper dolls" to move the suspension and steering components through their paces on paper so that they are compatible with each other before you start making hard parts. That's what finally put the icing on the cake for me.

I proceeded to design and construct an IFS that had zero bump steer through 9 inches of total wheel travel, zero scrub and 3 1/2 degrees of camber gain on bump.

Once you've read Smith and understand him, go back and read the post at the beginning of this thread and let's see what goes through your mind