Tension rod adjusts toe?? WTF?

[sr20dorifto]

Ok. I just installed a used set of SPL tension rods on an S13 I just purchased from a friend. I took it to a shop with an alignment rack. I was under the car trying to adjust the caster... which I first noticed to be at about 1.5 degrees on the passenger side. So I start working with that side. I turned the rod as far as it would, and I could see the wheel moving forward. However, the alignment computer wouldn't register any more than 2.5 degrees of caster.. The other thing I noticed is that going up to that amount of caster.. I know it's still really low... threw my toe in by 2 degrees. And unfortunately the stock tie rod ran out of adjustment at 1.10 degrees. The other thing I noticed is that the tie rods are different. The driver's side is silver and needs a larger wrench to turn. The passenger's side is a stock piece. I've already decided that I'm getting a whole new set of inner and outer tie rods obviously.

My question is why is the tension rod adjusting the toe more than it's adjusting the caster? AND why will it only go to 2.5 degrees and the other side is maxed out at 5.8 degrees... still low..??

[naed240sx]

Man you really need to talk to somebody who knows their stuff. None of what you are saying makes sense.

First of all, s chassis will start out with at least 7 degrees of castor after being lowered. Any decent alignment machine should be able to read this.

In addition, everbody knows that changing castor changes toe. This is why you set the castor first, then the toe. Your stock toe rods should not have run out of adjustment, and you should NOT have 2.5 castor on one of the sides. Your frame is definately tweaked or you messed something up on the install.

[gumby74]

Well that is strange. I may just be old school, but in my world toe is measured in inches, which for the front should be zero. The caster angle should read between 6* and 7*, though I run 8* myself. The toe changes because of the angle that the t/c rod is connected to the lca. It does not pull straight forward, but rather at an angle. Is anything bent at all? That just sounds like a case of something being bent.

[a_ahmed]

uhm not that i know anything or am any kind of expert in any of this but... if ONE side is different than the other side... then what do you expect? If you have one type of tie rod on one side and a COMPLETELY different one on the other side... then obviously something's going to be different, eg; one being able to be adjusted more than the other and something screwing up. I don't know, just a thought. And whatever others said above.

[naed240sx]

replacement(non oem) tie rods sometimes look different. I've run one oem and one autozone tie rod before. Works fine. they are the same dimensions.

[SmithSR]

Who initialized the heads on the alignment computer and does that person know what he is doing? And, as previously stated, tc rods pull the lc along an arc. That doesn't explain the out of this world readings you're posting.

[sr20dorifto]

I set up the machine and the sensors. I know what I'm doing. I haven't been at it for much more than a few months, but I've been trained to properly operate the machine and sensors. Looking under the car again, it makes sense that the TC rods pull at an angle. But I don't understand the crazy caster readings.. especially when I can see the wheel being pulled forward. Anywho... the only thing under there that is still stock.. and possibly damaged... are the lower control arms. So, I'm gonna get a new pair for both sides and give it another shot. Maybe I'll take it somewhere else and have them do it to see if maybe something is up with the machine.

[sr20dorifto]

Side note: Could having S14 control arms be causing this? I understand they are longer.. correct?

[URAS]

Side note: Could having S14 control arms be causing this? I understand they are longer.. correct?

S14 (r33 too) lower arms only effect static camber not caster.

specs should read something like below;

front toe 0-5mm toe out7-9 degrees caster2.5-3.5 degrees camber

rear 0-3mm toe in0.5-1.2 degrees camber-4mm adjustment on the traction rod. to keep bump alignment correct.

[AmoebAssassin]

While adjusting caster changes toe it is by an almost insignificant amount. It is still good practice, however, to set caster before toe.