Need Help on bushing replacement and monoball installation
 

Finally, I got time to start working on my car again since my baby boy arrived. With both the engine and tranny out (for quite some time), it's a good time to install the monoball on the control arm and replace the spring plate bushings at the same time. I've read both Chuck's and Bruce's articles before I tackle the task. Here are questions: I use polyurethane bushings for the spring plates. Instead of snug fit, it fits quite loosely on the spring plate. Is it normal? Secondly, I have some trouble fitting the monoball into the control arm. I heat it up a bit but no luck. It's still pretty far from sliding the cartridge in. Any clue? Please help!
Andy
'87 Carrera

As far as the spring plate bushings - yes, they slide freely on the spring plate. I think the inner bushing will continue to move freely even when installed in the torsion bar tube. However, if the outer bushing is pressed into the spring plate cover without some trimming, it will probably cause the inner diameter to deform and bind on the spring plate surface. Thus requiring turning down per Chuck's procedure.

Can't help you on the monoball fit. A word of caution though: there has been significant debate on the use of aftermarket bushings and monoballs in the rear control arms. Most people here seem to be of the school that says "use factory control arm bushings under almost all circumstances". The reasoning that has been given is that the control arm needs to be able to move slightly in three dimensions at the attachment point in order for the suspension to move properly. The monoballs and aftermarket bushings do not allow this 3D movement.

Note: Not sure if they're available yet (think they are) but Chuck was getting ready to sell spherical rear bearings which don't interfere with toe settings: http://www.elephantracing.com/suspension/frontmonoball/frontmonoball.htm

I installed both plastic bushings, and monoballs for the trailing arms/spring plates on my car. The plastic bushings fit pretty well, I just ended up chamfering the shoulder where the bushing fits onto the torsion tube and the outer holder.

To pursuade the monoball I just used a little grease a piece of threaded rod and some suitably sized sockets.

The suspension moves really freely and easily now, I can move the rear suspension through its full range of motion one handed!!

Pic of my high tech press!!

I am not sure of what you mean by "loose" fit of the polyurethane bushings. The ID will be correct from the factory. The OD must be ground away carefully to allow the bushing ro rest either in the cars body or the outer spring plate support passively with no play as to interfere with the ID. As far as the trailing arms monoball replacement, we just did this on a 87 and YOU MUST remove the inner steel reinforcements of the softer aluminum trailing arms for these to fits. You have two choices. One is to pry and hammer these out carefully as not to damage the soft aluminum. The second and better choice is to run a hacksaw blade through the opening, reconnect to the saw, and saw the steel reinforcements until cut through. Then squeeze them together and remove.

Thanks for you guys responses! As I found out this evening too, 89911, I need to get rid of those steel inner sleeves. I was about to ask how to take them out. I guess I'm going for the hacksaw method with a lot of patient. As for the bushings, should I shave the bushing itself or file the housing (for the inner one)? Thanks again!

Andy
'87 Carrera

Andy,
What housing are you referring to for the inner bushing? The torsion bar tube?! I think you'll find it significantly easier to shave a poly bushing than you will a steel tube! The outer bushing fits into the spring plate cover or "housing" but again, I'd not recommend shaving it. This wouldn't really be feasible. Shave the bushing, young Grasshopper.

Thanks Dave! Will post the result and ride quality as soon as it's done.
Andy
'87 Carrera

Dave,

The front suspension spherical bearings are available now. The rears are about two weeks away from shipping.

Chuck,
I'm aware of the benefits of monoballs on-track, but I'm concerned about impact on street driving. Can you outline and pros/cons for street driving? The rest of my suspension is going to be quite a bit stiffer than stock- adjustable sways, heavier t-bars, stiffer shocks, poly bushings all around, etc.

Andy,
What kind of rear monoballs have you got? Spherical (Chuck is anyone else making these or have you got the market cornered??)

Dave

Dave, I'm guessing you're asking about road vibration transmission.

The front spherical bearings really don't transmit much vibration because they are isolated from the suspension by the shocks.

The rear sphericals are connected directly to the trailing arm so you get a bit more vibration than you would with stock rubber bushes. However, I don't consider it objectionable for a street car. It's certainly less vibration than you get from front poly control arm bushings.

Sphericals eliminate the alignment wander caused by compression of rubber mounts under corner loads. But if the rest of your suspension components are flopping around, you can't really appreciate the improvement much. That's why sphericals are best used on cars that have other performance suspension mods like torsion bars, sticky tires, triangulated strut brace, and solid suspension bushings.

Sphericals also allow free suspension movement and eliminate the binding which can be a problem on the rears.

It's your future, I see it...I see...a..a sale...

Damn Chuck, You've been busy. I haven't been to your web page in a while, and now there is all kinds of new stuff.

Tom

Dave, I got a set of Smart Racing.

Andy
'87 Carrera

Just wait till next week. I've got something cool brewing!

Here's a hint - if you need suspension bushings, you might want to hold on ;)