Any thoughts, internet articles etc on alignment of the dropped axle, 4 bar, on a 32??? All parts are new.
Printable View
Any thoughts, internet articles etc on alignment of the dropped axle, 4 bar, on a 32??? All parts are new.
How to align a front I-beam axle.
Install the front axle and spring and shackles, letting the thru-bolt in the springpak extend up thru the hole in the center of the crossmember.---That centers the axle. Put on the clamp pad and bolts that restrain the spring in place to the crossmember and lightly tighten it just enough to remove any "flopiness"
Set the chassis up at close to ride height on jackstands under the outer ends of the rear axle and under the spring-perch bolts of the front axle. Assuming you know the height of tires you are going to run, try to get the jackstands adjusted so that the rear axle centerline and the front spindle centerline are exactly 1/2 the tire diameter off the floor.
Use either a plumb bob and string or a large carpenters square to transfer a mark from the outside of the rear of the framerails to the floor, at both sides of the car an equal distance from a common point on both frame rails.
Do the same at the front of the car.
Make a line exactly half way between these marks at the front and at the rear of the car, and connect them with a marker and a long straight edge. This establishes the centerline of the chassis.
At some arbitrary point about 12" to 15 " behind where the front axle will set, use a large carpenters square to make a line about 30" long on each side of the centerline, at exactly 90 degrees to the centerline.
Using the carpenters square and tape measure again, measure from this new line to 2 points on the front axle which are equally spaced about the centerbolt in the spring/crossmember. (I use the perch bolt on each side). Tweak your axle around (it will pivot on the centerbolt thats stuck up thru the hole in the crossmember) untill the measurement is equal on both sides of the centerline.
The axle is now setting "square" to the center of the chassis.
Try to approximate the weight of the finished body and engine package on the chassis to settle the springs down to ride height.******
Adjust the 4-bar or hairpins so that the top of the kingpin on each side of the axle is leaned towards the rear of the car at the top by 4 to 6 degrees. (This sets your caster)
Bolt the front tires on and adjust the tie-rod untill the tires are 1/8" closer together at the front than at the rear when measured at center height of tire from the floor---this sets your toe-in.
Then tighten up the 4 bolts restraining the transverse spring to the frame crossmember. Be sure and torque these bolts equally on both sides of the centerbolt, or you will actually squeeze the spring more on one side than the other, and your car will set low on one side.
*******This step can be deferred untill you have a body and engine if you are building a new car and don't have them yet.
If you are running one of Henrys split wishbones, many people make a relief cut about half way thru the wishbone on the underside just behind the axle, then heat and bend the wishbone (using a big pipe-wrench on the axle) untill the caster is set to where you want it, then weld up the sawcut. I am not a fan of this last method, but it does work. Before you do this, you have to establish exactly where the trailing end of the split wishbone is going to attach to a "home-made" bracket hanging off the frame and have that end of the split wishbone anchored securely.
Thanks for the info I will give it a try.