Thread: front crossmember angle

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The I have is a ford axle - I'd be happy with $250 and shipping... email me at tdavis32 @ earthlink.net

I'll get you some pictures if you like.

I would like to elaborate a little more on the front cross member angle and the importance of doing it correctly and the reasons why this is such an important part of a build. I only want to focus on caster and what it does. Other things come into play with this, like the Ackerman theory, but I want to focus just on caster.
Their are two things that directly affect the amount of caster needed in a good handling car. One is the weight distribution of your car, front to back. The more weight you have on the front end the less caster you need to make it handle properly, conversely the less weight the more caster is needed to keep the wheels tracking properly. If you doubt this look at the difference between a top fuel dragster and a supper stock Ford.
The second thing is personal preference, how fast you like the front end to return after going threw a turn and what is comfortable driving on a highway. The more caster you run the less the car wants to turn, so when you make a turn the wheel will center itself more quickly.
I like a lot of caster in my cars, I like it to pretty much drive it self going down the highway.
O.K. I'm almost done. So when you install your cross member all these things come into play. So how much do you need, well like I said before, you need to know the angle of the finished project, rake, weight distribution, and personnel comfort. You really don't want any bind in your front end, this means you need to know what you are going to wind up with. In a '32 roadster with 2 degrees of rake and a stock wheel base with a steel motor and a 4 speed, 6 degrees is good. I use aluminum motors and aluminum 5 speed and I stretch the wheel base so I run about 8 degrees.
Now all of this is just my opinion, things I have learned over the years. Will a car go down the road straight with 2 degrees, yes, probably. But will it be a more enjoyable experience with 6 degrees and no binding, yes, I believe so.
Just some food for thought, I'm nobody, no expert, just somebody who enjoys his Hot Rods.
Ken

It's an apples & oranges comparison I know, but I have my "Z" (strut ft. end) set @ 10°. I was told by Art Morrison anything over 150mph = 10°. Seems to go along with what Ken just said.

Originally Posted by pro70z28

It's an apples & oranges comparison I know, but I have my "Z" (strut ft. end) set @ 10°. I was told by Art Morrison anything over 150mph = 10°. Seems to go along with what Ken just said.

Not really it is all the same, in a race car you really want it to track by itself, all you want to do is make slow corrections. Going down the highway the speeds aren't the same but you want the same results. Correct caster is really important. I would run 14 degrees in my pro stocker.
Ken