Fwd: DIY generic Wheel Alignment, my tools, procedures, and specs.

[Bernie Benz]

Begin forwarded message:

> From: Bernie Benz <b.benz at charter.net>
> Date: December 25, 2008 5:07:54 PM PST
> To: Kris Hansen <kris at audiworld.com>, tech at audiworld.com.
> Cc: Tim Jee <ocsheepdog at gmail.com>, Stephen Kendrish  
> <skendrish at hotmail.com>
> Subject: DIY generic Wheel Alignment, my tools, procedures, and specs.
>
>
>
> Tools:
> For Camber measurements you’ll need a carpenter’s framing square  
> and a level. Also a 5’ straight edge and a fairly level garage floor.
> For Total Toe measurements, two steel tape measures, and a pair of  
> home made toe boards. I’ll describe mine as follows:
> Two flat and straight 1 x 6 x 24” pine boards. Saw slot the ends 1”  
> deep, parallel with and ½” in from the edges, to accept the tape  
> blades.
>
> Procedures:
> The DIY alignment procedure is an iterative process that can be  
> very time intensive the first time if misalignment is gross and  
> adjustments are frozen, but it is possible to better that of  
> sophisticated equipment in the hands of the unknowing using gross  
> factory tolerances.
>
>  1. Calibrate your level in degrees per bubble movement as follows:
> On a flat table surface, shim the low end of the level to center  
> the bubble.
> Flip the level end for end on the shim. The bubble should remain  
> centered. If not your level is NG!
> Now add a measured shim to move the bubble one division or one  
> bubble length.
> This added shim thickness divided by the length of the level is the  
> tangent of the level’s one bubble angle.
> Look up this angle in your trig tables and mark the level as such.  
> X deg./ bubble.
>
> 2. Check the floor for level.
> Chalk scribe the tire contact patch areas where camber is to be  
> measured.
> With the 5’ straight edge across the two contact areas (shim  
> equally if straight edge high centering is a problem) check the  
> straightedge for level. Note what portion of a bubble it is off  
> level and in what direction. This correction factor will be applied  
> to subsequent camber measurement values.
>
> 3. Camber measurement, one axle.
> With the tires for the axle to be checked on the patch areas, hold  
> the square edge vertical against the tire side wall, contact points  
> just fore or aft of center to avoid the contact bulge, check bubble  
> with level on horizontal leg of square. Apply the floor correction  
> factor and you have Camber for that wheel in bubbles, which can be  
> converted into degrees using your level calibration figure. Repeat  
> for second wheel on that axle. If the camber angles of each wheel  
> are not equal, equalize them by moving the subframe before  
> attempting to adjust individual wheel camber.  After any camber  
> adjustment, back the car off of the contact patch areas and  
> reposition prior to the next measurement.  Make all necessary  
> camber adjustments before proceeding to Toe measurement.
>
> 4. Total Toe measurement, one axle.
> Position car on contact patch areas with steering wheel in exact  
> neutral position. Place toe boards edge on floor against and  
> centered on wheels. Stretch tapes under the car fore and aft of  
> wheels in the toe board slots. With tape ends hooked into the
> opposite toe board, pull tapes tight against measuring side toe  
> board. The difference in tape lengths is the Total Toe angle in  
> inches per 24”.
>
> This Total Toe angle must be centered on the chassis such that the  
> car goes straight down the road, not crabbing. To check this, hold  
> your straight edge horizontal at axle height across the tire side  
> wall‘s two contact points and measure the distance between the  
> straight edge and the base of the B pillar. Repeat for the other  
> side. These two measurements should be equal.
> So, when correcting Total Toe angle make your adjustment on the  
> side required to also center toe on the chassis. After each  
> adjustment, the car must be backed off the alignment patches and  
> the patch position reestablished for another measurement.
>
> After measuring and correcting the alignment for the first (front)  
> axle, repeat the whole iterative process for the second (rear) axle.
>
> Alignment Specs for maximum tire life:
>
> Front and Rear:
> Camber: Zero. Identical L. to R. No tolerance.
> Total Toe: Zero, no tolerance, Centered on the chassis.
>