Front Alignment to stop Corded Tires

[jmn444]

Tire dia is a factor in that equation also. It’s not math, it’s trig.

I think the calculators use that, but it should only matter at the distance you are actually measuring, ie my toe plates are 24" so i compute it based on that distance. If measuring at the actual tire diameter then .1 degree would be more than the 1/16" that it is at 24". still .1 degree though. using strings you are measuring off the tire, but likely not at the full diameter, more likely on the bulge or even on the wheel lip... if you are using the number the calculator gives you based on outside tire diameter, you could end up with more toe than you wanted. prob not significant enough to matter though, we are talking like 1/128" which is far more precise than I can get it to anyway haha. slightly over 1/16" is what works for me currently. and about 3/16 in the rear if i recall correctly.

also keep in mine some of us have suspension components with rod ends or poly that have less deflection than oem, so results may vary on what works best if you start modding things.

I think honeybadger runs only 1/16" in in rear but my car felt super loose at that setting.

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[BeastAR]

So maybe I should drive these one more season but I dont know if safety is an issue with corded tires.

If cord is showing, time to change. Very unsafe and a ticketable offence if driving on the public roads. If the officer so chooses.

 

[JAJ]

I've been doing my own alignments for years, and it's pretty easy once you get the hang of it. The one caution that I'd offer is that after you make your changes, always take a test drive and measure again. It's worth taking the time to make sure you ended up with the setting you wanted.

It's also important to take care when you're positioning the car for the alignment. You have to center the steering wheel and roll the car without moving the wheel for the last 8 feet or so to the place where you'll be measuring. Otherwise, you put tension into the steering and suspension and you'll get erroneous measurements.

As for the alignment itself, I measure toe at the rim using strings. Measuring at the tire lacks precision - tire sidewalls are not perfect. Rims, on the other hand, are pretty good. 19" rims have the outer edges of the rim flange 20.5" apart.

Measuring with strings is pretty straightforward. You set them parallel with the car's centerline with the steering wheel centered and then measure from the string to the rim flange at the front of the rim, then again at the back. The difference in the measurements indicates toe-in or out.

At 20.5" apart, 0.1 degree of toe or camber is 0.9 mm. To get 0.1 degree of total toe-in, the forward flange of the rim has to be 0.5 mm further from the string than the rear flange on each side. With that measure on both sides, you have a total of 1 mm, which in turn gives you total toe-in of 0.1 degrees.

The tools required are pretty simple too - I have two 6' lengths of pine with knife nicks in them exactly the same distance apart (far enough apart to clear the sides of the car - distance doesn't really matter so long as the nicks on the sticks are identical). The string is 30# fishing line masking taped to one stick and fed through the notch. The other end has a 3 ounce fishing weight on it. The sticks are set on top of jack stands front and rear so the string passes the wheels at the centerline. You center the car between the strings by measuring from the rims to the strings so the car's centered front and back. Dead easy - takes about 10 minutes to check toe this way and it's amazingly accurate.

 

[galaxy]

It's also important to take care when you're positioning the car for the alignment. You have to center the steering wheel and roll the car without moving the wheel for the last 8 feet or so to the place where you'll be measuring. Otherwise, you put tension into the steering and suspension and you'll get erroneous measurements.

Only thing I would question or argue on this, would be using toe plates, no? Now you're lowering your car down onto something that'll let the suspension completely relax, or realllyyy darn close. Or do you still disagree with that?

As for the alignment itself, I measure toe at the rim using strings. Measuring at the tire lacks precision - tire sidewalls are not perfect. Rims, on the other hand, are pretty good. 19" rims have the outer edges of the rim flange 20.5" apart.



At 20.5" apart, 0.1 degree of toe or camber is 0.9 mm. To get 0.1 degree of total toe-in, the forward flange of the rim has to be 0.5 mm further from the string than the rear flange on each side. With that measure on both sides, you have a total of 1 mm, which in turn gives you total toe-in of 0.1 degrees.

Oh yeah, exactly. I don't think anyone would use the tire, would they? The front and the rear of the rim for sure. Thanks for the tip on the numbers.

 

[galaxy]

I've been doing a ton of snooping around this site also. May even just buy this string set up and his camber tools.

https://www.smartracingproducts.com

Any opinions on this place/training course?

https://www.racecrafthq.com/courses...DgMVXGMlwONgGAFi5d23W-MTARssneKJN6FOGtIVjrg1w

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