Toe in adjustment method

[HoltForest]

Reading through old posts, I saw mention of setting the toe in using the "Two Bob and Masking Tape" method. I am intrigued. Can someone enlighten me please?

Thank you, Roger

[Steve Simmons]

I suspect it means hanging two plumb bobs from the tires and see where they hang at the ground, then do the same at the rear. Measure the difference in distance between each set, divide by two, and you have your toe setting.

[HoltForest]

Sorry to be obtuse, but could you clarify that a bit for me.

Do you drop a bob from the centreline of the front of the right hand tyre to the ground and mark, then drop the bob from the centreline of the rear of the right hand tyre to the ground and mark?

Repeat for the left hand tyre - all on the outside edge of the tyres, not under the car.

You now have four marks on the ground.

Then measure between the front and rear marks. To round off the numbers for simplicity, if the front measures 10 and the rear 5, isn't the toe-in 10-5 =5? Why then divide by 2?

Thank you!
Roger

[ferricsteed]

Another 1 person operation. Put a stick pin in the tread, forward most part of the two front tires. Tape measure the distance. Roll the car backwards one half revolution. Measure between the 2 pins. Delta is the toe. In reality, you probably can't get the pins half way up the tire, you have to position somwhat lower depending how low to the ground the car sits.

[Steve Simmons]

That's why some people use bobs. You can measure from 90-degrees to the ground. If measuring at the tire with a tape measure, you could do it at 45-degrees downward and double the reading. And that's where I got the divide by two thing because you can't measure across on a TC (or many other cars), total brain meltdown. Sorry about that. Just measure the difference.

What I would do if using the bob method would be to pin a string to the center of the tread on each tire. Roll the car so both strings are at exactly 90-degrees forward. Tie a plumb bob to each string so it sits just above the floor. Once they have settled, mark each spot. Then, roll the car so the wheels go to 90-degrees rearward (don't run over the bobs) and do the same. Now measure between each set.

What you're doing is measuring how far in or out the front of the tires are from straight ahead. So by measuring the difference between them, that will give you this number.

[HoltForest]

Thank you, that all makes sense. I’m going to try it!

[JayF]

I just bought this
https://www.googleadservices.com/pagead ... EB4&adurl=
and am going to try using it this weekend
I will keep you posted

[Steve Simmons]

It's worth noting that tire size affects the measurement. The most accurate way to measure is using degrees rather than inches.

[rstarkweather]

FWIW, I use this on my MGB race car:

https://www.summitracing.com/parts/lng- ... gLou_D_BwE

Put one plate against the front wheel/tire on each side of the car. Measure the difference between the plates at the front of the tire (say 49 3/4 inches), and the rear of the tire (say 50 inches), and subtract the two. In this example, that would be 1/4 inch total toe in (as the front is narrower than the rear).

Then divide by two, so you get 1/8 inch toe in on each side.

[Steve Simmons]

I used to have a set of those, but most of my cars are old and the wheels aren't that straight, so the readings were a bit unreliable. They seemed to work well on modern cars with low profile tires, or old cars with alloy wheels.

[HoltForest]

So, in this example you have 1/4" total toe, 1/8" each side.

When toe-in figures are quoted, are they total or each side?

[HoltForest]

And, forgot to ask, with reference to setting the toe in degrees, do you know what that value is for a TC with 19" wheels?

Also, I presume that the toe in figures stated for T-Types is for 19" wheels as they would have to be greater for 16" etc wheels?