wheel alighnment math ? I.E. Toe in

[57chevyragtop]

2002 Impala 122k I replaced lower control arms and outer tie rod ends. The spec is for 0.10 degrees toe in....can anyone convert this to inches or mm. I know there is a way to do so but have been unable to locate that particular table. 16 in. wheels.
I hope someone has this! Yes. I do know this does not equate to an alignment done by a machine. I'll do that when new tires are put on in a month or so.

[57chevyragtop]

I decided to set my toe-in at 1/32 nd. front of rim center each side. seems to work ok on test drive so I'll leave it there for the time being.

[j cAT]

Originally Posted by 57chevyragtop

I decided to set my toe-in at 1/32 nd. front of rim center each side. seems to work ok on test drive so I'll leave it there for the time being.

when the vehicle bounces the toe will change. if the toe is too little you will have a tough time keeping the vehicle going straight on a rough road. I have set the toe in at 1/4 inch. this seems to work well at keeping the vehicle from wandering and not cause excessive outer tread wear.
as an example I have over 60K miles on my truck with all the tires exactly worn the same across the entire tread. about 60% worn .

if the camber is off the vehicle will , pull need to keep this so that the tread is flat to the ground.

[57chevyragtop]

You are right about being a little too neutral on the toe. I ended up bumping it to 3mm on each side. I still need to get tires and an alignment when I have the finances. 1/4" (6mm) seems a little much on a 16" wheel.

[j cAT]

Originally Posted by 57chevyragtop

You are right about being a little too neutral on the toe. I ended up bumping it to 3mm on each side. I still need to get tires and an alignment when I have the finances. 1/4" (6mm) seems a little much on a 16" wheel.

my truck has the 16 inch wheels.

[57chevyragtop]

Yes I thought you might have 16" wheels on your truck. However I would guess you have a taller sidewall than a passenger tire 225-60-16....also consider my toe spec is 0.10 deg. (read one degree). I do not know the spec on your truck. If 0.10 deg. you are probably right on @ 1/4" depending on where you are measuring. The mfg. spec is for the center of tire at tread diameter. A taller tire will account for the difference.
Now if you lay it out on paper you start by laying a line the length of the radius from which you are going to measure on the vehicle i.e. (center of wheel to front lip edge) Mine measures 8 5/8" or 219mm. Then using a protractor centered at the start of the line draw your deg. line out then measure the distance between lines 1/8th inch = 3.175mm.
I don't think it a good idea to use tread as a measure point due to possible run out in tread design tire to tire. This is merely an opinion on my part

[j cAT]

Originally Posted by 57chevyragtop

Yes I thought you might have 16" wheels on your truck. However I would guess you have a taller sidewall than a passenger tire 225-60-16....also consider my toe spec is 0.10 deg. (read one degree). I do not know the spec on your truck. If 0.10 deg. you are probably right on @ 1/4" depending on where you are measuring. The mfg. spec is for the center of tire at tread diameter. A taller tire will account for the difference.
Now if you lay it out on paper you start by laying a line the length of the radius from which you are going to measure on the vehicle i.e. (center of wheel to front lip edge) Mine measures 8 5/8" or 219mm. Then using a protractor centered at the start of the line draw your deg. line out then measure the distance between lines 1/8th inch = 3.175mm.
I don't think it a good idea to use tread as a measure point due to possible run out in tread design tire to tire. This is merely an opinion on my part

I do not know about this tread you say . the wheel is used to provide the toe as I have done this. the alignment I use Is with using a line from the rear to the front then adjust the wheel for the toe of 1/4 inch same on both sides steering wheel exactly straight. I place two steel plates under the wheel on each side . with grease between these plates , the wheels move very easy . then adjust the tie rod for the proper toe. then move steering wheel a few times and recheck.

using a cut piece of wood on the wheel rim to stick out beyond the tire at the center point allows all this to be very accurate.

now I am with this procedure for almost 20 years now and my tires wear really even.. like I stated before they all are worn the same all worn same amount across the total tread surface ..
my truck tires first set from the factory had 92K miles on them and 70% worn. the tires now 2nd set , have 60K on them and are 60% worn more wear because these tires now are 8 years old !!

[la1]

I do not have access to an alignment machine. I have been looking at some home type alignment devices. There is also a lot of videos on you tube showing how to do front end alignments at home. I would assume you could use a tape measure and measure from the front of one tire to the other and do the same for the back. or the string method. I am going to try one or all of these at home methods in the spring when I use my HFT tire remover installer. I did have to do a tie rod end replacement in may, I marked where the old one was. Seemed to be on the money.

[57chevyragtop]

j CAT.. after further testing I tried your method as you explained it and find it seems to be correct as the results are much better. I did not however use the metal slide plates so it did take several attempts to get there. The slide plates would make this work much easier. my problem became getting the steering wheel centered properly.. Anyway thanks for your persistence in convincing me.

[j cAT]

Originally Posted by 57chevyragtop

j CAT.. after further testing I tried your method as you explained it and find it seems to be correct as the results are much better. I did not however use the metal slide plates so it did take several attempts to get there. The slide plates would make this work much easier. my problem became getting the steering wheel centered properly.. Anyway thanks for your persistence in convincing me.

glad to hear you got this procedure down. The reason I began this was because tire shops have unskilled workers using the wrong spec's and uncalibrated alignment equipment to set the front end components. because of the steering wheel play , this can be a PITA only because the tie rods adjustment is hard to change very slightly to get this exact....... all my vehicles go straight on flat roads wheel exactly centered. many vehicles I have rented even new dealership test drives the wheel is always to the driver side..........with the variable ratio steering this causes issues with steering wheel control turns to driver side quicker than pass side......

[57chevyragtop]

I think in a way you just described my aggravation after I get an alignment done professionally. My steering is always canted to driver side. And when I leave and take it back and say it's off they ask me what I did to it...pita for sure~