techno toy tunning tc rods

[kully 560]

well I installed the ttt adjustable tc rods today for anybody that might be thinking about them . the ride was tighter and more responsive,nice improvement over the stock rods with poly bushings .put about 20 miles on from smooth roads to semi rought roads and the feel in the steering wheel is not any more than the poly bushings these rods are very beefy as compared to the oem crap

[Zed Head]

these rods are very beefy as compared to the oem crap

How about some reasons for why you say the OEM rods are "crap". The more technical,the better.

I'm always interested in learning something new.

[jmortensen]

I don't know that the stock part is "crap" either, but if you want to see what is wrong with them generally speaking, take one off of any Z car and set it down on a table with the end that bolts to the control arm hanging off the table. Roll it. There is your answer. It's not very technical, I admit, but I have yet to see one that isn't bent.

Adjustable caster is a pretty huge benefit too IMO. John doesn't seem to like these things and I get why, but having used something similar and felt the difference at autoxes I would say that the benefits far outweigh the penalties for someone like me. There are better designs available too, but this one isn't bad IMO.

[kully 560]

these are much heaver, the stock rods are 9/16" od and the new ones are 3/4" od alot more rod diameter also I needed to be able to adjust .I do not think these will bend

[Zed Head]

set it down on a table with the end that bolts to the control arm hanging off the table. Roll it. There is your answer. It's not very technical, I admit, but I have yet to see one that isn't bent.

I have noticed that they're not straight, but since it appears to be a forged steel piece, not machined and built from straight rod, I can't be sure that they're not designed that way. It would make sense to form some pre-bend in to the piece to give it some shock absorbing properties.

For the original purpose of the car, an inexpensive sports car with good performance, it seems like it suits the purpose just fine. They only seem to break when mismatched bushings are used. There was no recall on them, and they lasted through 8 design years. I'd feel like I had accomplished my goal if it was my design.

The TTT TC rod is an upgrade but I wouldn't call the original crap. I just wanted to see what kully was thinking.

Edited March 5, 2012 by Zed Head

[jmortensen]

these are much heaver, the stock rods are 9/16" od and the new ones are 3/4" od alot more rod diameter also I needed to be able to adjust .I do not think these will bend

IIRC, stockers are .630". It's either a hair over or under 5/8".

[kully 560]

we are looking at a 40 year old design did it work yes ! but with today tech. new and improved. I changed my caster by extending my tc rods longer and my z now turns much more easy with the steering wheel then before and the car handles alot better

[jmortensen]

Increasing caster should increase steering effort (the wheels lean into the turn--the more they lean the taller they get--so you're effectively lifting the front end of the car with the steering wheel). Heims joints are not exactly the new hotness. They were developed by the Germans in WWII, and you can see pics of old postwar Jags with rod ends all over the suspension.

http://web.archive.org/web/20060621014121/http://monstertower.com/HeimJoint.htm

[tlorber]

Kully, how do you compensate for caster in the LCA bushing? Do you just force the control arm forward with the TC rod, or do you somehow shim the bushing?

[LeonV]

Kully, how do you compensate for caster in the LCA bushing? Do you just force the control arm forward with the TC rod, or do you somehow shim the bushing?

A heim-jointed LCA is the better solution, with regard to LCA misalignment.

[tlorber]

K, thanks.

[kully 560]

right now I have not had a alinement ,but when I purchased my early 260z in 1979 I did not no it was hit in front drivers side! when it was fixed by unknow bodyshop they mounted the tc rod support back a little to far and as a result my steering wheel was always harder to turn at slow speed like backing up and turning the wheel to go forward.the aliment shop in 1997 could not set caster to proper specs . we got as close to spec as we could ,I do not know or remember how far off, but I know it was off a little. back in 1997 I purchased from msa the nissan adjustable front caster adjuster kit .you really do not get that much adjust out it but it helped.the rubber bushing are now shot that came with it. so I decided to put the ttt tension rods on and set them about 1/2" past old measurements and what a difference .I measured the caster center of wheel to wheel and now I have 90.25" center to center.I need to get the car alined to set @ factory or should I increase caster a little?