toe setting

[mbaker76]

What is the best way to set toe, all on one side or split evenly. We have always set it by centereing the center link in the frame then setting the LF straight with the car and putting all the toe out on the RF.

Now when i think about it, and i admit i havent taken any measuremets, i wonder if it would be better to do it the opposite, set all the toe on the LF. My reason is that with the camber on the RF leaning the tire in at the top, then i would think that to minimize bump steer that tie rod would need to be shorter as well, because of the shorter upper control arm length, then on the left side the tire leaning out the tie rod would need to be longer for the same reason.. Make sense, i havent messed with it any though. just wondering if anybody else has?

[billetbirdcage]

The only difference between changing the Left tie rod length verses the Right tie rod length is mostly how far it will turn in that direction. If the steering was centered and you lengthen the LF tie rod to get the toe out the car would turn more to the left then the right.

Generally you would lengthen the RF tie rod so the car would turn more right then left. On a LM the rack isn't necessarily centered when the tires are straight ahead as we want to turn right more then left.

A lot of chassis will have a dimension for the LF tie rod and then adjust the right to get the toe, this will set the centering of the rack to where they want it at.

Yes the lengths will alter the bump steer but usually very minor unless you making large changes and is easily adjusted when you setting the bump steer.

[mbaker76]

Ok I see what you mean. When I set the toe with the drag link centered and then push the RF out for the toe then to go straight you have to turn back to the left just a little, so i can see where that would give you more turning ability to the right, never thought about it that way.

what do the late models generally run for toe out, We used to run 1/8-1/4 but last year it got knocked out to about 1" and driver said the car entered the corner a lot better, turned in more on its own, so we have been running 3/4" or so since then. People look at us kind of funny, I dont know how many people come up and tell us the toe is off..... but it works.

[billetbirdcage]

Typically toe out on a LM is around 1/4" to 3/8" as standard, but lately there has been a trend to run upwards of 3/4" or more.

Adding toe out is an easy way to help the car turn, to a degree. If you get to much it may become darty. It will also help scrub the front tires on the straights to build some heat and keep them closer to the rear temps. How much you need would depend on how much ackerman the car has built into it.

[mbaker76]

Thats kind of what I was thinking toe out is sort of like instant of constant ackerman. I figure the LF is nearly completely unloaded down the straight so it the RF is really doing most of the steering, then as you get to the corner and start to turn in and let the car down the LF which is now pointed furthur toward the infield with the extra toe out helps pull the car into the corner. On a stock stub i dont know how much ackerman is built in, but i am guessing not very much. It seemed to make the most difference for us entering the corner when we ran more spring rate split in the front, stiffer on the LF. My guess again the Once the LF was getting loaded into the corner it started to have more influence on turning in, the stiffer spring just amplified it.....am i on the right track there?

[billetbirdcage]

Yes, your on track.

How much the LF needs to be turned more the the RF is dependant of the radius of the corner. Wider tracks will need less and tighter cornered tracks need more, it will also depend on the front wheel track width also.

I would rather have to much toe out or ackerman then not enough in most situations as long as the car doesn't become darty.

[all_jacked_up]

With a steering box, it is important to keep the box centered, then set the toe on each side as you see fit. The steering box has a high tooth in the middle of the travel to keep backlash very tight at the straight ahead position. If you get very far off center, you will notice a lot of play in the steering wheel. The factory boxes have the high tooth marked on the input shaft end of the box. The mark should be straight up when the box is centered. If you have ever bent a center link, you will notice the extra play in the box if the steering wheel has moved from its normal position.. When you replace the center link & the box is back to center, the play is gone.

[mbaker76]

I could see that on a street car but on the track it seems like you are rarely ever steered straight ahead, so the box isnt centered anyway.