Hot Rod Forum banner

bushings rubber or urethane or alunimun

3K views 12 replies 10 participants last post by  bulldogmafia 
#1 ·
Hi everyone as I'm getting my 80 Z28 ready for the spray booth I need to replace a few worn out bushings.
First and formost the stock rubber body mounts are shot,I will replace them but with what,money is not an issue I've heard rubber is the cheapest and softest for ride control,polyurethane is very strong and will last but they have been known to squeak which will drive me bannas,finally there are aluminum mounts ultra strong but what about ride comfort. The car has a 60 over 10:75comp-1 sbc010 block xr268 hyd comp cam with matching components, heads are fullyported and polished bronze guides etc,2.02-1.60 5 angle valve job roller rockers rpm intake 800cfm edelbrock carb. The car runs sweet from the moment she fired up m21 4 speed 3:42 out back.
As for the cars overall handling i will remain stock appearance but will putting urethane mounts all over the car help that much,if I'm going to do it it will be done front to back with 1/3/8 front sway bar and rear 1"sway bar stock springs fo my kidneys and I are doing just fine last is the shocks,kyb?koni/Bilstein qa1 monroe sensatrac I want the car to glide over the streets without the chiropracter feeel yet car corners as if it were on skates.

any feedback would be thankfully received and greatfully applied Thanks To All
 
#3 ·
i would agree on the air shocks. i have kyb's on my cavi. but they do make a nice ride. firm yet comfertable and they do let you hug the road pretty nicely. i work at an auto parts store and the sensatrac's are nice but you can do a lot better. their more for a daily driver. with air shocks, you can adjust the ride to your liking.
 
#6 ·
I've got a '78 Trans Am that I've been building up over the years, and this is what I've got for my suspension:

- Graphite-impregnated urethane bushings all-around
- Graphite-impregnated body mounts
- New performance-type coil springs (WS6-style)
- New 5-leaf leaf springs (slightly firmer than the stock 4 leaf)
- Koni Classic adjustable shocks all-around (set about mid-rebound)
- Competition Engineering bolt-in subframe connectors
- 1 1/4" front sway bar (stock)
- 5/8" rear sway bar (stock)

Out of all that, the subframe connectors made the biggest seat-of-the-pants difference in body roll, but I am extremely happy with what I went with (though the front rides a bit high from the coil springs). I haven't noticed any squeaking from the bushings, but the ride quality is stiffer than before - hitting a pot hole is really noticeable, and it'll transmit noise from going over bumps more as well (I once was wondering where the rhythmic "klunk" was coming from in my drivetrain - then I realized that it was the seams in the concrete :D). Course I don't have any sound deadener at all so that might account for some of the noise. As for overall stiffness - I'd put it at slightly firmer than a stock '00 LS1 Trans Am. It still doesn't corner like the '00, but it is a marked improvement.
 
#7 ·
I think you'll get mixed reports about urethane bushings. I put graphite impregnated bushings in my 96 Impala SS and they started squeaking almost immediately. I greased them at every oil change and they stayed quiet for about 3 weeks then started sqeaking again. Urethane is also not very resistant to tearing, so if they bind at all they'll tear. My urethane bushings are completely shot after 65k... like one side is worn the whole way through to the metal shell. I think I got crap bushings since most people don't report that bad of an experience, but the ride harshness along with the noise and wear mean that I won't do it again. I think I'm going to do aftermarket control arms with rubber bushings. Stiff parts, soft connection between them.

Another thing to consider is how much friction the bushings add to the movement of suspension components. The best suspension has no resistance to movement except the springs and shocks. Rubber is pretty fair at that since its durometer is nice and flexy. Urethane is not. For instance, if you put urethane bushings on the front lower control arms and install the arm, you can usually stand on the ball joint and not move the arm.

One of the best for not adding resistance are the Delrin bushings, but of course they will transfer a lot of impacts to the subframe and your kidneys.

I'll also throw this out there. F-bodies (as much as I love them) are very flexy unibodies. Stiffening up the suspension won't have the benefits that you might expect. Its like putting a stiffer suspension on a marshmallow. Not picking on your car... I've had 4 F-bodies and loved them all, but you might want to look to other methods than upgrading bushings if you are worried about ride quality.

One way to really upgrade things is to weld in some subframe connectors and find other ways of stiffening the body/frame. Then upgrade the rear with a panhard bar.

Think of it this way; the stock suspension pieces are a little flexy. The stock body is really flexy. The bushings between the two aren't the weakest link. Stiffen up the flexy parts, not the bushings between them. I think you'll be very happy. You can stiffen things either way, but stiffening flexy parts always has bigger benefits than stiffening the bushings between flexy parts.
 
#8 · (Edited)
Had an '81 Camaro w/a 468 in it, was pretty quick. Took it to Orlando Speed World and on the first pass w/slicks (no sub frame connectors, drag shocks f&r) it cracked the windshield.

At first I thought somebody threw a coke bottle at me, but we discovered that the body flex along w/a windshield that I replaced that was installed a little close on the drivers side, was the culprit.

So, yeah, they flex.

EDIT- The disclaimer to this is, the w/s was installed w/that urethane adhesive usually used for air bag equipped cars. I've since been told that stuff's too rigid when cured, and that it was what caused most of my problems.

But when one tire is up a foot and a half and the other is firmly planted on the pavement...
 
#9 ·
bushings

Sorry boys forgot to mention that the first thing I did when I got the car was weld in a pair of Jegs subframe connectors and whow did they make a difference,cut out 90% of the squeaks and stiffened the car big time, Mr Curtis 73 do you or does anyone know if any one makes a panhard bar for my 80 Z any help boys.
 
#10 ·
Back in the day there were a few. It wasn't as common since its a leaf spring car and because most guys were interested in straight lines, not curves.

I might suggest getting a stock panhard bar from something similar, like maybe an 82+ F-body and welding in some tabs to hold it. Edelbrock makes a really beefy panhard bar for 82+ F-bodies that you could adapt in. Well... edelbrock doesn't make it; someone makes one and Edelbrock puts their sticker on it :)

Hotchkis makes a ton of suspension upgrades for all kinds of GMs. maybe check with them.
 
#12 · (Edited)
I personally hate poly for any bushing that moves or rotates. Anti-roll bar end link poly bushings normally don't squeak and will make it a bit stiffer in roll. They have no rotation so they don't bind up the suspension. Sub-frame bushings I'm sure would be fine. Poly trans mounts tend to bring vibrations into the cab so even though there is no movement I tend to not like them there.

For A-arms I would rather use steel-on-steel with no lube than poly. Delrin makes for good bushings (as long as they are fitted well) but transmits vibrations like stated before. For the street I think the best compromise is High-Durometer Rubber bushings like those in Moog's "Problem Solver" line. If they are available for your application use them! I got my last set from www.rockauto.com for a good price (to replace poly bushings that bound up the suspension, squeaked, and wore out after 4 years).

Check out Edelbrock's IAS shocks. They have a patented valve in them that "knows" if the wheel is moving or the body. They aren't cheap but it sounds like ride and handling are what you are looking for.http://www.edelbrock.com/automotive_new/mc/shocks/shocks_main.shtml
 
#13 · (Edited)
Urethane bushings getting bad rap?

I agree with Jim, body bushings should not squeak, they are usually blamed for a body noise that is something else entirely, and as far as suspension, it is 9 times out of 10 the installer. Let me elaborate, heres where almost EVERYONE fails and of course the poor bushings get blamed, leave all suspension bolts LOOSE until vehicle is on the ground, then if you wanna get real tech like, try and simulate your body weight in the drivers seat, ie, bags of concrete/ barbell weight plates, whatever, and the amount of fuel you will generally be running, whether you are a drag-racer, or autocrosser, or in general a half tank---THEN, and only then, tighten all of your suspension fasteners, and YES you should torque them. Yes also spend the $6 and use the recommended lube specically for the poly bushings. Unfortunately, most people tighten everything down while the car is on the lift, jack stands whatever, putting your new bushings in a bind, and ultimately to their premature demise. Good luck with your project!!! :thumbup:
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top