The Camaro Club (UK)

Need to replace the wishbone bushes, and a few others, what do you guys recommend, Poly or OEM.?

Also what suspension upgrages would you recommend, I cant afford the full Hotchkis or Heigts system, but I can weld and fab, thinking 4link rear with coilovers all round...my first Z28, your the experts!

Hi Paul,

Most people go for poly all around. It's easy as it comes in kits. When you read into it, it's strongly recommended to use rubber on the Lower Control Arms (wishbones). I've got poly all around and so do a few people and it seems ok. For my next project, i've got rubber for the lower LCA's based on what i've read.

The way rubber bushings work is a little bit different than what you expect. It's normal to think that the shaft in the bushings rotates, and it kind of does... Poly and delalum bushings are designed to turn a full 360 degrees, acts like a bearing. Rubber though, it's tension, it's not designed to spin freely. The best analogy for this is, hold your arm in front of you, across your body parallel to the floor i.e. holding out your left arm, your left hand should by touching your right arm. That's your shaft. Now your right hand will be the bushing - hold your arm with your right hand,and pretend there's a metal rod between your right elbow and hand. Now, move your right elbow up and down so that your right hand is twisting your left arm. See how you can move your right arm quite a bit, even though your right hand is gripping your left arm, and it's your skin is moving? That's how rubber bushings work - they are constantly in contact and stretching to twist. Poly and delalum on the other hand (no pun intended), you can demonstrate by now loosening the grip of your right hand, so that it glides over your arm, instead of grabbing the skin and twisting. Poly / delalum work like in that way - designed to spin freely. The issues that i've read about with using poly on the lowers, is that it causes binding, as it's not a perfect rotation - it receives sideways forces, creating an angle etc. and when in movement, it could spin freely but then suddenly catch and as it's not like rubber, it won't stretch as easily (as it's not designed to), so would catch and the impact has to be absorbed somewhere, so it would pass it along the chain and put extra load somewhere else and possibly cause deformation of the LCA. Sounds a bit extreme lol but when you read it into that's the kind of stuff that comes up. The LCA's are high load compared to the uppers which is why you could do ploy upper, rubber lower.

Best thing for the rear leaf springs is the Energy suspension full kit, comes with shackles and bolts. I made the mistake of buying just the bushings. What happens is you take the bolts out and realise you don't want to reuse them, if you've managed to remove them without cutting them. Shackles will be pitted and may get damaged when trying to remove the bolts, so you'll likely want to change them once it's sat on the floor and you question the stability of everything I ended up buying the full kit ($119) after trying to keep the cost down and going just for bushings ($59) but ended up paying 1.5x the full kit cost. Just wanted to share that so you don't make them same mistake as me I'm good at making mistakes lol.

But if you're going for a completely different setup (coilovers etc) then the kit would come with all bushings etc. Most second gens i've seen over here have leaf's and they get raced too. I'm not sure how much there is to gain with coilovers, i'm sure it's better as modern cars don't have leafs anymore but maybe that's partly a weight thing too. I would say that unless you're autocrossing / racing etc. and are counting to 0.00, then there woudln't be much to gain from a conversion. I would save the money and put it towards keeping it well maintained.

Having said all that though - it's your car so definitely build it the way you want and the way that makes you happy. Sometimes people enjoy modding for the sake of it, so it's ultimately a case of how you want the car to be. There's not much fun in keeping them all the same. I just wanted to share my thoughts and experience but by all means feel free to ignore and go with what makes you enjoy the car the most.

Whatever you decide on let us know, if you go with coilovers would be good to see the conversion process as i don't think anyone on here has done one, would be interesting to see how it all goes together!

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I've got a slightly different take on the rubber/poly/delrin options. I can't claim to be an expert, but here's what my research has lead me to believe....

As Ray already said, rubber bushes don't move freely, but the rubber twists. The downside and hence bad rep for rubber, is that over time it perishes and then start moving in more directions than they should. That said, when new, rubber bushings are very good - you just need to plan on replacing them sooner.

Poly was introduced to remove the extra movement of rubber, i.e. less flex, and will feel like a massive difference compared to worn rubber. I'm not sure if they are intended to properly rotate, but they are notorious for binding (especially if not properly lubricated), resulting in poor performing suspension. The problem with most poly kits is they aren't designed to be re-lubed, so will eventually dry out and start binding.

Delrin (del-alum) is intended to fully rotate. The main body of the bush is aluminium, designed for zero flex. Then there is a delrin (type of hard wearing and low friction plastic, think teflon) sleeve which is what rotates. These are typically designed with grease nipples, so you can keep them lubricated. These should give the best movement performance and last the longest, but as you would expect, are the most expensive.


Personally, I've gone for the Delrin. If it wasn't that, I would go with new rubber. In actual fact, I have delrin on the front and rubber at the rear (until budget allows them to be upgraded too).

I was watching the bushing install vid posted by Ray in another post and they had a reasonable good page discussing Rubber Vs Poly.

http://www.aftermarketsuspensionparts.c ... -bushings/

Thanks for clearing up the explanations on delrin and poly! Makes more sense now Delrin is definitely the cream of the crop. I may have some poly bushings for the rear shackles (all 8) if you wanted? I don't have the shackles, bolts or front eye bushings, just the bushings for the shackles. I'm off to the U.S in the morning though, so won't be on here for the next couple of weeks, so please bare with me.

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Pretty much as explained.. depending on the intended use of the car of course...
If it's a road car looking for a bit better handing and grip the the standard leaf design rear isn't bad, it just needs fine tuning with decent springs, bushes, good shocks and roll bar.
the front is a pretty good design already and also just so the same as above.
if you can fabricate and weld then chassis stiffening is a good aim, as subframe connectors and G braces are worthy addictions .

If you're going down a drag racer thing then 4 bar an be useful, as allows more tyre width if mini rubbing the rear,but it's a lot more work.

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Thanks guys, plenty of great info.. I looked at the subframe connectors, they hang a bit low for my liking, will look at this though..

Four link, its a maybe, I already have some coilovers on another build, was going to bag it.

really not a fan of cart springs but they do a reasonable job, may get them reached and add a leaf.

whatever I do I will keep you in the loop, but need to respray it, microblisters are killing it..grr that's covers over winter for you

Don't discount SFCs, they are one of the best things to add, and cheap if you can fab your own. The ones on mine are very simple and add less than 2 inches to ground clearance. The exhaust is still the lowest point on the car.

If your a good fabricator you can do through floor connectors. Means cutting a bit of the rear floor out though..

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Think I will make up some SFC as a start.. may do the cutting the rear to get them up in there!