T-C Rod Kit

[dst1]

I bought a 70 240 that the previous owner had installed a Black Dragon Performance Tension/Compression Rod Kit. Does anyone have any experience with this kit? I don't believe it allows the suspension

to move properly. Any help would be great.

Edited February 7, 2010 by dst1

[jmortensen]

It actually works pretty good. It's a good idea to grease it up and check for wear about once a year or so. What does inhibit movement is the bushing on the back. Some people put polyurethane back there and that is totally unnecessary. Best thing to do is use the old, worn out rubber bushing in back. The less resistance to movement you have, the better, so the stiffer the bushing is, the worse it is in terms of both ride and parts wear.

If you really feel a need to change it, I'd suggest a rod end or ball jointed setup like you see in the following links:

http://forums.hybridz.org/showthread.php?t=152585

http://www.technotoytuning.com/productdetail.php?p=668

These have no bushings at all and the metal on metal joint moves extremely freely by comparison, reducing friction and making braking more stable. The metal joint does transmit more NVH to the cockpit if that matters to you.

[Zs-ondabrain]

It locks your suspension from moving backward under braking and gives you a more positive feel on the suspension. The suspension still moves properly. It's basically a cup and ball as aposed to the soft rubber that used to be there and move too much.

I have the T/C kit on both of my Z's.

Dave

[tlorber]

Those look awesome. Just found another back burner upgrade.

[billyjarrell]

I actually installed the MotorsportAuto kit very similar to that on my 280 just last week. So far everything works great. I already had the poly bushings installed so when I put the ball/socket style joint in the front I just took the center sleeve out of the rear poly bushing allowing the T/C rod to move more freely.

[jmortensen]

I actually installed the MotorsportAuto kit very similar to that on my 280 just last week. So far everything works great. I already had the poly bushings installed so when I put the ball/socket style joint in the front I just took the center sleeve out of the rear poly bushing allowing the T/C rod to move more freely.

What you might consider doing is drilling the poly bushing. Go to www.dimequarterly.com and search "poly bushing" and you'll find an article about drilling them out. With the G Machine bushing in front the rear bushing doesn't do anything except take loads when you're backing up and hit the brakes, so the easier the TC rod can move, the better.

Here's the text from that article:

One of the most noticeable changes you can make to your car's handling is to replace the old rubber suspension bushings. By now they are well past their useful life and should probably be replaced. This was all covered in a previous DQ article, and one of the recommendations was to replace the stock Tension/Compression (T/C) rod bushings with Energy Suspension polyurethane bushings.

For a street driven or an autocross/street car, I think this is the best option. Parts are easy to come by, simple to install and maintenance free. However, I found an unpleasant side effect from these bushings that I thought I would share.

On a recent trip across town, I experienced the failure of my passenger-side T/C rod. I hit a small bump, heard a pop and noticed a slight pull to the right, but didn't think much of it as the car still went FAIRLY straight. I drove the car home and took the wheel off to find the problem. I nearly had a heart attack when I noticed the T/C rod had snapped in half at the shoulder behind the bushing. Not a problem at 30 M.P.H. on a city street, but potentially VERY damaging on a tight lefthander at 60 mph.

I'm surprised we haven't heard of more failures like this. Even though I've attempted to restore the stock front control arm angle by using bumpsteer spacers, my T/C rods are still angled up in comparison to stock. Between that and the stiffer bushings, the T/C rods experience much more stress than they do at stock ride height.

In light of this experience, I suggest modifying the polyurethane T/C bushings. I drilled six 5/16" holes around the perimeter of the center mounting hole. These should allow the T/C rod to pivot more easily and still offer the advantage of the stiffer bushing when braking and/or cornering. I recently replaced both of my T/C rods with a set from a car that had never been lowered. I also had that set Magnifluxed to be sure they were still in good shape. I shudder to think of the consequences of a high-speed failure.

And here's a related thread on Hybrid Z:

http://forums.hybridz.org/showthread.php?t=87758

[dst1]

Thanks for the feedback on the T-C Rod Kit. I have discovered I

have little strut action in the front. I can barely get the car to

move. I know the previous owner had a garage completely

go through the suspension and steering. It looks like they

possibly missed the struts. The rear is loose and the front

barely moves.

Edited February 8, 2010 by dst1