Straight/Dropped front axle camber ??????

[Jbird]

My next project involves building my own tubular dropped front axle. I haven't decided what spindles to use so I was wondering about camber. Is it built into the axle or into the spindle? This car, in my mind, weighs less than 1000lbs. What kind of camber angle should I be shooting for? I have very limited experience with straight/ dropped axles.  TIA
 Jbird

[enjenjo]

The caster is built into the mounting or the axle itself.  Most axles are made with no caster built in. Spindles have no built in camber, it's not possible, because it is the angle of the kingpin that makes camber.

As to the amount, most factory setups used 4 to 6 degrees positive camber, a light car can use more, up to about 10 degrees, which would be pretty radical on the street. Drag cars use as much as 30 degrees.

camber in the axle would be 1 degree or less usually.

[29abone]

Most solid axles would have approx 0 deg to .25 deg pos camber.  I believe Engenjo is probably talking about caster.  Camber is the angle of the wheel as viewed from the front, caster is the angle of the kingpin as viewed from the side, and toe-in is the angle of the tire as viewed from the top.

Larry

[GPster]

From what I understand the caster will depend some on the type of spindles you use. The spindles have a kingpin inclination built into them that is matched by a like angle in the axel. Any camber that is built into the set-up is a difference between those two angles. Normally caster is built into the wishbones to set the axel at the needed slant back (positive caster) or accomplished with adjustable ends on the 4-bar or wishbones. A look at the alignment specs for the car the spindles came off of will give you a minimum caster starting place and Enjenjo's suggestions will follow from there. If I remember correctly the kingpin inclination on early Ford spindles is about 6 degrees and they normally can use/handle/require more caster than Chevy car/truck spindles that are set at a 4 1/2 degree kingpin inclination. The October issue of Rod and Custom has an article that will explain some of the basics. It is on the newsstands now with a picture of that '32 Ford coupe with the $30,000.00 paint job that Jimmy Shine was finishing on television. GPster

[enjenjo]

Most solid axles would have approx 0 deg to .25 deg pos camber.  I believe Engenjo is probably talking about caster.  Camber is the angle of the wheel as viewed from the front, caster is the angle of the kingpin as viewed from the side, and toe-in is the angle of the tire as viewed from the top.

Larry

Yes, you are right, I didn't take time to read it carefully.  I was typing camber, but thinking caster. I changed things to make more sense.

Long time, no see Larry.

[Jbird]

Thanks dudeees............ I'm gonna use four link suspension linkage so the caster will be adjustable. I'm also gonna try a rack & pinion steering setup. If I run the steering shaft from the wheel down to the frame just in front of the fire wall then parallel to the frame out to the rack, with a slip joint in it, I think bump steer won't be a problem.  Frank when I first read your post I was picturing a big yellow road grader. I'll post pics as progress evolves.   Jbird

[GPster]

I'm also gonna try a rack & pinion steering setup. If I run the steering shaft from the wheel down to the frame just in front of the fire wall then parallel to the frame out to the rack, with a slip joint in it, I think bump steer won't be a problem.     Jbird

Listening to the "slip joint" horrors got me to wondering. Chrysler Product that had the emergency brakes on the tailshaft of the transmission had a style of driveshaft front universal joint  that was a different style of slip joint. My junkyard memories have me remembering a smaller version of those slip joints on steering boxes. It was probably be a '58 to '64 GM product or a Chrysler product from around that time as I think Ford was the last manufacturer to get away from rear steer boxes and steering boxes that didn't include the long steering column shaft. I would think they would allow better than 1" of slip that would be more than a "rag joint would allow.  Power take-offs on farm and other earth moving equipment  might also have some type of slip joint and maybe "big" cab-over trucks where the cab tilts foreward for access to the engine. I'm not sure when but I'll have a tubing front axel that was made by M.A.S..  It's 47" wide and has a 7" drop. It was made for use a pair of leaf springs and there are no mounts welded to it. The axel was made for Ford spindles and has a pair of '48 spindles mounted with Chassis Engineering dropped/cross steer arms and '40 Ford drums and brakes. I'm planning the Jeepster to go the S10 direction. GPster