replace tension compression rod bushes

[Jimbo]

Any advise appreciated....             I am going to replace my t/c rod bushes but what with??. I have read (1) rubber is best---  then some say too soft  (2) poly is best--- some say too harsh  or (3) replace the front bush with rubber & rear bush with poly, the best of both worlds. This is what I have read on various forums!!
                 So what has anyone on here done with their cars..  Thanks  Jim

[Gareth. J.]

Hey Jim, I've gone the solid front t/c kit(from ebay). These are supposed to stop castor change under braking/cornering by eliminating any compression in the bush. My brother runs them in his daily 1600 and thinks they're good also.

We both found less wandering when braking and more direct steering particularly while cornering, with no added harshness. I guess it may be over kill for a daily, kinda depends on what driving you will do. Track, daily, weekender?

Check these out...    http://cgi.ebay.com/ebaymotors/DATSUN-510-610-710-T-C-Kit-2851610-G-Machine-/260818285606?pt=Motors_Car_Truck_Parts_Accessories&hash=item3cb9fb3426

[zr240]

Got a link for that kit gareth?

Would like to get or make a set

Ash

[Gareth. J.]

Added link above. 1600/510 are the same kit as 240z.

[DAZDA]

Like Gareth has pointed out, it depends on what you plan on doing with the car.  If you are considering track days, etc then polyurethane bushes or spherical joints are a must for geometry control under pitch and roll.

In my opinion, the polyurethane bushes really aren’t that harsh.   A factor many people forget is how much ‘crush’ (preload) is put on the bush once the retaining nut is done up.  Some poly bush kits have shorter crush tubes giving more preload on the bush.  More preload = less give.

[Jimbo]

Thanks for the replies Boys,      My car is certainly no rocket,  now a weekender, occasional trip away & the odd sprint track day. I would like to find out if anyone has heard of the rubber/poly combination & what the outcome was.. Thanks  Jim

[Whittie]

Thanks for the replies Boys,      My car is certainly no rocket,  now a weekender, occasional trip away & the odd sprint track day. I would like to find out if anyone has heard of the rubber/poly combination & what the outcome was.. Thanks  Jim

I went the full poly route and snapped the T/C rod and almost my neck in a possible accident so now religiously tell people to avoid full poly! I was barreling down the back straight at 200 kph, down hill in to a 90 degree right hander, and had the right hand T/C rod snap at the bush. I can tell you I made the corner without hitting the sand, I even didn't brown my pants but MY GOD it was close!

If you want to keep the standard rod then you use poly on the front to keep from compressing and away from all the altering geometry goodness under braking and a rubber bush on the rear to make sure there is still play enough so the rod doesn't snap due to stress. Think of the rod like a paper-clip. If you use poly front and rear there is so little movement in the mount that the rod is constantly bending under suspension movement, eventually, just like the paper-clip, it will snap. Rubber on the rear allows the rod to move vertically without allowing it to squirm around under heavy braking loads.

Personally, I have gone to and swear by Techo Toy Tuning spherical ball jointed T/C rods, but they really are a race only mod and are excessive on a street car, not to mention likely illegal.

[Jimbo]

Thanks Whittie,  I think I will stay away from poly and stay with the OE rubber front & back, which I can get.  It sounds like you were lucky to get out of your predicament without any damage or injury.   Jim

[Whittie]

Don't get me wrong, poly it's still a very worthwhile upgrade around the whole car, you just have to be careful with the t/c rods. Everywhere else benefits enormously from the installation of poly bushings and they're likely cheaper than oem parts too.

[Gareth. J.]

Pretty lucky escape there Whittie, especially at track speeds. I do recall seeing a beautiful Yellow Alfa gtv break a T/C rod in targa, sent him off into the shrubs and trashed the car.

The T/C kits come with a measuring gauge to ensure the bushes are not overtightened and allow enough movement to prevent flexing the rods. I ran urethane for around 7-8 years, it was one of the first mods I did to the car when I got it, T/C rod bushes as well.... Maybe it was just luck that mine survived. I've never really paid that much attention to them, but I think from now on I'll be removing before events and checking them for straightness, twisting, corroision, streching of thread.

It's the first I've heard of it on a zed, could it just be 30+yrs of stress and fatigue... Corrosion?

[Whittie]

Very lucky escape! It was simply stress, the rods looked in fantastic condition. It was the first track event after the old man and I did 1000 k's around bathurst at the old FOSC meeting, so my guess is the dipper broke it.

We'd raced the car for 5 years before this happened so it was very unexpected. However, the zed gurus around the country all said they'd heard of it before and use the poly and rubber trick to avoid it. Stewert Wilkins also does a custom, thicker, threaded rod that looks good if you need/want a standard looking part, otherwise for the same price you can get in the TTT rods. Be careful with them too tho, as I had one of the retaining nuts come loose and fall off :s I seem to be cursed with these rod issues!

However, I came away fine and now just spend that much longer going over the car between events on the day and have a pretty extensive between race meets check list.

[DAZDA]

... and had the right hand T/C rod snap at the bush.

Whittie, did it snap at the end of the threaded section or at the step where the larger washers sit?



P.S.  MS Paint for teh win   

[Whittie]

Snapped at the front, at the step you've indicated. almost had the wheel collapse under the car.

[Paulo]

I installed the Stuart Wilkins T/C and he gave some advice re the poly products - he has experienced several customers cars with advanced deterioration with a certain product (I will leave it up to you to enquire/do your own research, but they are still on the shelves and are blue in colour).
The T/c is certainly stock looking, but I doubt if you will have any problems with the retaining nut he supplies.

Whittie, may be the way to go?

Paulo

[handsandwhich]

My rod is thicker than standard 

The rods that are on my car do not have the step down like in the drawing that DAZDA posted and are 17mm thick the whole way through so they limit the stress point where they normally can break.

I have got one of those t/c bush kits like the one below, but since it won't fit over my large rod, I am willing to let them go if someone wants them for $25 + postage.

http://www.ebay.com.au/itm/170700782324?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649