How much caster should I run in my 32. Looks like I have too much. How do you guys measure it and what does it do for me. I'm not trying to sound too stupid. I just wnt it to track and turn well. Any advise would help.
I like to start with 6 degrees, then + or - up to 2 more depending on how it drives. For best results find a good alignment guy. The Wizzard
I'm not as good as some relating my thoughts. so here goes.Caster is the inclination or laying back of the kingpin angle in a straight axle car. In a ball joint car this is an imaginary line between the ball joints. The larger the number the more it is layed back,it will be measured in degrees with straight up and down as 90 degrees. So a plus 7 degrees will be 7 degrees from straight up and down. Do you know why they stick the front wheel on a chopper way out there,that is to change the caster. The more caster the better it will handle at high speed. The problem is every degree that you change the more effort it takes to turn the wheel and to keep it straight. Look at the caster angle from the side ,the imaginary line hits the ground somewhere in front of the tire. Because of this the tire tries to rotate around this line,when you start to turn the tire tries to fall and the further you turn the more weight keeps pushing the tire sideways and it wants to flop on its side. when you try to return it to straight ,you have to overcome this flop and actually raise the weight of the car on it's wheels thru the steering wheel.We have all seen choppers do this. That being said I try to set race cars at 7 to 14 degrees ,the lighter the car the more you can go because of the steering effort.Street car that are light can go to 10 degrees but chances are you will be happy at half that. Hope this helps -email me if I need to explain any clearer.
Beat me to it, and as an old front end alignment man well done JoeCool. Jhogan. I think if you were to check back through threads on the subject you would find that somewhere between five and eight is usually the norm. As the others said, after that it gets down to fine tuning it so that it drives the way you want it to.
Good explanation by Joecool. One more thing, make sure you check caster at ride height front and rear while on level ground. Caster is measured relative to level ground, not relative to the frame angle. As a quick example, if your caster is 7 degrees and you swapped out rear tires for big tall tires, you increase the rake and lose caster. 7 degrees BTW is what I go for on straight axle stuff.
Anywhere between two to seven degrees should work. I tried 10 degrees once on a street-driven Willys and it was too much.
Yeah, Joe has it all just about covered. But how heavy the steering is, and how well the steering self centers also depends on the weight over the front wheels, and the diameter of the front wheels. A chopper motorcycle or a slingshot dragster could run 45 degrees of positive caster because there is almost no weight over the front wheels. Try that in a full bodied street car with a big block motor and not even Superman could steer it. As has already been suggested, around six degrees for a typical light frame street rod would be a good start, but if the whole car has a lot of forward rake, remember to measure caster from the ground not the chassis !
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