The silicone bushings will make it a little rougher. What coilovers do you have?

 

I'm gonna have to check my paperwork

 

Is this a race car? Why did you go with a race type setup? Poly bushing and coil overs will make you feel every bump. Thats why Datsun put rubber bushings in their suspension.

 

I blew it based on the garage recommendations. I just wanted an enjoyable ride over some rough roads in the Chicago area.

 

You're getting the exact ride those parts are designed for.

 

As the old saying goes, "Be careful what you wish for; you may get it."

It ain't the bushings. It's the suspension you just installed.

 

Any source for rubber bushings? I need to replace all of mine, and I'm nervous about going with polyurethane for the reasons stated above. I'm struggling so far.

 

You can still get stock rubbers from Nissan, theZstore, Zcardepot, and rockauto.com.
I don't mind poly bushings... they look nice and last forever, but they are not comfy on the road. unless your city streets and highways are perfectly smooth, that ride is going to suck. I only get poly bushings if the stockers are no longer available, this includes engine mounts, diff and gearbox mounts, and suspension bushings.

 

Yup, just as everyone above has stated, the new coilover suspension is making your ride rough, by design. I am not knocking coil-overs, but I can't figure out why in the world guys feel the need to "upgrade" to performance suspension and pay thousands of dollars to do so, only to daily drive or take it out once in a while. Performance coil overs are really better suited for racing applications and driving on flat smooth surfaces such as a nice race track. Adjustable for racing purposes. but for bumping around town? no way. every Z driver to his or her own, but if you want a nice smooth ride for your Z, put the stock suspension back in, get some nice KYB or Koni or Tokikos (if you can even find them anymore) and put stock rubbers on, and your car will drive and feel like a dream.

 

Poly bushings do transmit more road shock and a bit more noise to the interior of the car. I tried them on my 280ZX and went back to rubber.

 

I did the same on my 280zx- had all the suspension down, decided to replace the bushings with polys, and my ride around town sucked. and then to top things off, I like to drive to my job on Fort Bragg in my cool old Z quite often, and Army roads here are an absolute disaster (pot holes, cracks, uneven pavement, gravel, 50 year old asphault... etc). And after few runs, I decided to take out the polys and put stock rubbers back in. much more comfortable

 

IMHO the only place to use Polyurethane is in the Steering Coupler to remove any vagueness between the Steering Wheel and the Rack-N-Pinion. Poly is phenomenal on the track along with properly adjusted dampers and coil springs biased or balanced for the specific track. My next S30 suspension build will be all OEM rubber, if available.

 

Yes! I have thought about the poly bushing for the steering coupler as well, but I thought it would be rough? I don't even think that OEM rubber is available anymore is it?
I have been picking parts off an old 86 300zx turbo car from a picknpull yard and guess what? it still had all its suspension bushings intact! I took 'em all
unfortunately the motormounts were broken (they always are on those cars)


anyway, happy bushings!

 

I used to have a 1969 Chevelle SS396 in the 70's that had really bad wheel-hop when I came off the line and back then the only option was solid-steel rear control-arm bushings, which gave a really bad ride. I bought a 'Hot Rod' magazine that had an article in it about fixing rear wheel-hop for cars with rear coil-springs and not using steel-bushings. It said to take off the control-arms and buy a box of steel finishing-nails the same length as the stock rubber-bushinggs. It then said to pound 5 nails (evenly spaced) into each side of the 5 rubber-bushings (40 nails total). Since 'Hot Rod' magazine was the bible back then, I did it and my wheel-hop disappeared, but you know I've never heard of anybody doing this back then or even now.

 

I have GOT to wonder about who came up with that solution!! What in the world........I also have to wonder how long the bushings would last.

And think about the next owner - bushings get sloppy, he buys new ones, and when he takes those out he goes "WHAT THE.....!!!!!!"

 

I put Poly bushes in my Z and was leery of the ride I would get. I did put in stock KBY shocks and lowering springs. I have to say I am very pleased with the ride quality. I have no doubt that rubber would be softer but it is not a harsh ride at all. I do mostly city driving here in Denver, and the roads are rough, and still I do not feel like I am getting beat around. My other daily drivers are German luxury autos so I can be pretty finicky on the ride quality I want. I wonder if the ride difference could be in the stiffness of the Poly bushes. Do they make different levels of stiffness? Just my personal observations.

 

Just put new poly's in the front, front end is much tighter now and just a tad bit harder on bumpy roads around East Tennessee but the trade off was well worth it in my 82 280zx, many years ago I had an 83 that had stock rubber bushings and it was tight and maybe a tiny bit softer ride. Did not do anything with my springs or struts because they seemed to be good

 

One more factor to consider is wheel/tire size. To quote Tyga, "too much rim make the ride too hard."
One more thing that probably won't make a huge difference in ride quality but may be a safety concern is to use rubber bushings on the front control/strut/tension rod mounts. Some people claim the poly bushings are so stiff they can contribute to the failure of the stock control/strut/tension rods.

 

One more factor to consider is wheel/tire size. To quote Tyga, "too much rim make the ride too hard."
One more thing that probably won't make a huge difference in ride quality but may be a safety concern is to use rubber bushings on the front control/strut/tension rod mounts. Some people claim the poly bushings are so stiff they can contribute to the failure of the stock control/strut/tension rods.

I agree. big rim and a thin tire doesn't make for comfortable ride thats for sure. I have heard that the poyl's can break on the 280zx tension rod, and its best to pair one poly with one rubber. I did this on my zx and haven't had any issue with breaking. but I still feel rubbers are best for daily driver comfort. track and racing, polys all the way.

 

I forgot about the torsion bars issues. I did put rubber bushes on the torsion rods because I heard the Poly is too stiff for them I also did wider tires, P205 60/R15 all around so I'm not riding on rubber bands. I did not have to do fender flares. I'm not a fan of that look. I wonder if a wider tire helps spread out the road impact somewhat? I never considered this possibility.

 

return it to stock setup, get correct stock rims and tires (no hotwheels inspired rims), all rubber back to OE, and you will have a nice decent riding 70's era performance sports car. FYI upgrades rarely are.

 

Silicon or Polyurethane? I regret putting Energy System polyurethane in. That along with a stiffer lowering MSA springs has made my ride harsh (and noisy).

 

hopefully the coil over is reversable, most or not. Start looking for some stock struts on ebay. Also the struts are rebuildable in stock form, some new o rings and replace the oil. Prob with a lot of modern replacement cartridge type is the gas charge "may" increase ride height. "may" since I have no 1st hand knowledge of this. Used to be able to by non gas charged carts. Of course if the springs have sagged it may all work out with kyb gas charged. I still like to rebuild the old ones when the shafts are in good shape (not rusted).

anyway just 2 cents.

 

Agree. I bought my 78 new and found the same thing after installing the Energy System polyurethane suspension along with MSA lowering springs. I already had KYB strut inserts which are great. Also had them in my 72 and loved them.

 

get some nice 14" steel rims and skinny tires to help with the rough roads. The tires will help absorb some of the stress. Pneumatic tires were invented for a reason. the stuff today with the super low profiles are not good on old vehicles designed around 100 year old technology.

 

There's a lot to be said for maintaining the car in an original or close to original configuration and enjoying it for what it was designed to be. Not everyone's cup of tea, but it appeals to me and many others.

 

This might explain a lot. It seemed to me that my '84 Z31 was in need of a rear suspension refresh so I changed the coil springs with new ones and also installed new KYB struts. Now I'm sure that it's worse. I feel like I'm going sideways should I cross RR tracks when travelling at 40+ mph. Where did I go wrong?!

 

I think your problem is more with the stiffer springs than the poly bushings. Yes the poly will make a difference, but stiff springs will make the ride very harsh. Do you know what spring rate you have?

 

Every one is trashing the coil overs and while they are correct in that they can cause issues. I have ridden in many cars that have gone to coil-overs and they have low profile tires that ride great. Poly bushings can add vibration also but again not always.

The Coil-overs that ride like crap are almost always cheap ones that are over sprung(to stiff of a spring) and under Dampened(normally not enough rebound control). I did not see the original poster ever say what he actually put on? What brand and what level of suspension. Suspension tuning is an art. I used to work as a pro motocross mechanic and getting spring rate and valving to work for the rider is the biggest improvement you can do for rider and it varies by rider. This applies to cars also. You cant use springs for a 260z and expect them to work for the same for late 280z. there is hundreds of pounds difference in weight.

My suggestion is to firstly tell us what you have. What are the weight of your springs and what kind of adjustability do they have? Preload only or do they have preload and ride height? What adjustments are there for compression and rebound and where are your adjustments at? Normally there will be clicks. Count the clicks while turning them in. Once we have that info we can actually make recommendations to improve your ride.

Everything stated before can be true. not arguing that. But no one is actually helping. They are just pointing fingers at the bushings and coil-overs and yelling to get off their lawn!!!

Shoot. Caster and camber can change how car rides.

 

You cant use springs for a 260z and expect them to work for the same for late 280z. there is hundreds of pounds difference in weight.

Know the dynamics and the loads imposed, esp when up sizing wheel/Tires.