1672 replies to this topic

[dattoman]

Rear bushes shouldn't be a problem

I think they come in 3 different duro (stiffness) ratings so need to decide on hard, soft or middle of the road

 

As far as a bush for the front.... will need some measurements ... should be able to work something out

[ls2lxhatch]

I think you will find that the SuperPro bushes can be turned down in a lathe. I have a couple of spares from an incomplete set to experiment with if you want. Personally I would just make a alloy bush for the top as well.

 

I am using this style of bush on the trailing arms. I have tubular trailing arms which I feel need either a soft bush or a bush that can pivot. I believe the factory arms will twist a bit under extremes of suspension movement whereas the tubular or boxed arms have no give at all and require either the bush or the mount to absorb the twisting movement.

[Toranamat69]

 I have tubular trailing arms which I feel need either a soft bush or a bush that can pivot. I believe the factory arms will twist a bit under extremes of suspension movement whereas the tubular or boxed arms have no give at all and require either the bush or the mount to absorb the twisting movement.

 

 

Spot on Andy.

Even if using a bush that can pivot, you then introduce a differnet ype of bind whereby 3 of the trailing arms are trying to change the length of the 4th one so you still need a compliant bushing in there somewhere or you will crack something.

 

I plan to replace the top diff bushes with rubber when I get the hatch home even though I have the soft poly in there now and those same type of pivoting bushes in the top front of the trailing arms.

[Uncle Chop Chop]

I am using this style of bush on the trailing arms. I have tubular trailing arms which I feel need either a soft bush or a bush that can pivot. I believe the factory arms will twist a bit under extremes of suspension movement whereas the tubular or boxed arms have no give at all and require either the bush or the mount to absorb the twisting movement.

 
 

Spot on Andy.
Even if using a bush that can pivot, you then introduce a differnet ype of bind whereby 3 of the trailing arms are trying to change the length of the 4th one so you still need a compliant bushing in there somewhere or you will crack something.

If the rear lower arm pivot points were moved so the lower rear arms became parrallel instead of diverging, would that help much?

[eyepeeler]

Thanks Neil, can you PM with cost of hard compound for everything rear end except the top control arms, will not need these.

I can get you the OD / ID and thickness early in the week for the sub-frame top bush.

Cheers mate.

 

Rear bushes shouldn't be a problem

I think they come in 3 different duro (stiffness) ratings so need to decide on hard, soft or middle of the road

 

As far as a bush for the front.... will need some measurements ... should be able to work something out

[eyepeeler]

I think you will find that the SuperPro bushes can be turned down in a lathe. I have a couple of spares from an incomplete set to experiment with if you want. Personally I would just make a alloy bush for the top as well.

 

I am using this style of bush on the trailing arms. I have tubular trailing arms which I feel need either a soft bush or a bush that can pivot. I believe the factory arms will twist a bit under extremes of suspension movement whereas the tubular or boxed arms have no give at all and require either the bush or the mount to absorb the twisting movement.

 

 

Spot on Andy.

Even if using a bush that can pivot, you then introduce a differnet ype of bind whereby 3 of the trailing arms are trying to change the length of the 4th one so you still need a compliant bushing in there somewhere or you will crack something.

 

I plan to replace the top diff bushes with rubber when I get the hatch home even though I have the soft poly in there now and those same type of pivoting bushes in the top front of the trailing arms.

 

 

Also imo its definitely best to run pivot rod ends on your torque arm set-up rather than a poly bush.

 

Tie/ Pivot Rod Ends are a great idea, but can't use them. I have to keep within the rules. For anyone interested, this is a link to the rules for Improved Production.

http://docs.cams.com...29_Group_3J.pdf

 

The ruling for this is:

9.3 Bushes: Elastomeric bushes used at suspension pivot points (which are not otherwise specified in these regulations) may be replaced by other elastomeric bushings.

&

9.10 Rear suspension components: Devices for the lateral location of the rear wheels on vehicles with a live axle, and any associated brackets on the body, are free. Brackets may be welded to the body. All other components which have any function in the location of the rear wheels must be retained unmodified except for bushings, which must comply with 9.3 above. Drive flanges, trunnions, hubs, stub axles and wheel bearings are free. It is permissible to add additional longitudinal rear suspension arms provided that all bushings are elastomeric and that the mounting points on the body only involve the addition of metal, save for a single hole per arm of maximum diameter 25mm.

 

I can replace all rubber bushes with Superpro or nolethane as they are considered elastomeric, rod ends are not. Another point to note is that where it says: All other components which have any function in the location of the rear wheels must be retained unmodified except for bushings, means I cannot replace or modify the 4 trailing arms off the diff.

 

What I will be doing is making the 2 top arm virtually redundant, and going for a 3 link set up with a Torque Arm as LXSS350 posted. Although the picture he put up whilst it might be a good bit of kit, I cant use because of the Pivot Rod ends.  

What I am considering using I what my mate who is building the Monaro I posted pictures of a few pages back suggested.

 Torque Arm.jpg   121.54K   9 downloads

 

I should note that in this picture it is only the torque arm and not the other gear in the photo I plan to copy/ use.

Good fun Huh, building a car within rules!!!!!!

Edited by eyepeeler, 03 August 2013 - 03:44 PM.

[eyepeeler]

I should also note that when you see me do the Watts link it will have rod ends , confused?? Well in the Rule 9.10 it says to use elastomeric bushes on Longitudinal arms (BLUE), lateral location devices are free (RED).

 

 

9.10 Rear suspension components: Devices for the lateral location of the rear wheels on vehicles with a live axle, and any associated brackets on the body, are free. Brackets may be welded to the body. All other components which have any function in the location of the rear wheels must be retained unmodified except for bushings, which must comply with 9.3 above.

It is permissible to add additional longitudinal rear suspension arms provided that all bushings are elastomeric

[eyepeeler]

For god sake do they want you to only wear pink jocks.   LOL.
 
You would think logic would mean that what's good for the non standard watts link would be good for the non standard torque arm. 
 
Dozens of ways to build a torque arm but a torrie certainly has not got an abundance of tunnel room (especially with a big tailshaft).

LOL Col, I'm hearing ya loud and clear. Fun isn't it. It's all good though, well it will be when I can get behind the wheel at Barbs and drive it.
Love your ideas though, you put some thought into things that you want to do.

[76lxhatch]

What I will be doing is making the 2 top arm virtually redundant

 

How are you going to do this in a manner that won't cause bind with the third arm if you still have to use bushes? Even with limited suspension travel isn't it going to be a problem?

[eyepeeler]

I read the rules but I must have selective reading comprehension (i.e. If I don't like it I skip that bit - LOL)

The way the rust is going with us I image come fire-up time Barbs will be a housing estate.

The standard torana LH/LX front air dam is very ineffective. I find running a deeper diffuser style like Clarkes with an undertray similar to the Germans (green taxi) works really well for stability when coming over the hill at 240kph and into the final corner. Pretty sure you can use similar as long as its no more than 125 forward and within the 100 ground level.

I have looked at the spoiler those boys use as it would be within rules as you say, haven't thought about the under tray idea.....hmmmm. Will look into that.

Edited by eyepeeler, 03 August 2013 - 09:00 PM.

[eyepeeler]

How are you going to do this in a manner that won't cause bind with the third arm if you still have to use bushes? Even with limited suspension travel isn't it going to be a problem?

This one will surprise and make you shake your head. Leanne Tander set the president from what I am told, she had the upper arms attached to the chassis in the original bracket but zip tied them up and out the way, not even connected to the diff, but the diff has to have the bracket to accept them. So that is how I plan to make them redundant. Either that or just a really spongey Wetex style bush. Lots of Elastomeric in that one.

[Toranamat69]

If the rear lower arm pivot points were moved so the lower rear arms became parrallel instead of diverging, would that help much?
 

 

Longer top arms and making them parallel to the bottom arms all helps but a 3 link is the only way to remove all the binding.  Packaging it in the car is then the fun bit.

 

The main point I was making was if using those pivotting bushes above does not mean you can then run everything else rock solid.

 

I have tried a few different setups over the years and have a few interresting things I can show.  I have a set of boxed upper arms here with poly bushes - I can show what happpened to the bushes after about 10K kms.

 

I then changed to edelbrock upper arms (which use pivotting front bushes) but didn't swap out the soft poly in the diff housing because it was too much effort at the time.  When I get my car back, I can show you some pics of the cracks in the UCA mounts - this was just from street driving and a few trips to willowbank down the 1/4. 

 

The force applied to the top arms on the diff under hard accelleration is in the opposite direction to where they cracked so I speculate the cracks are from the binding in the suspension bushes and not enought flex.

 

I will be changing the upper diff bushes for rubber and obviously welding up the cracks.

Edited by Toranamat69, 04 August 2013 - 11:08 AM.

[eyepeeler]

Any progress????

Not this week mate, have hurt my back and it's really slowed the movement up!
Caught up with OzyOzy on Sunday last, he has got the rotor hats done though his mate at HighSpeed Engineering, they look really good.
Should be able to pick them up soon,
Nice to see Mark from Race Product on here, looking forward to seeing the diff being built.
Will catch up with Neil (Datto) this week and get bushes sorted

Hoping my back sorts itself out soon as its bugging the hell out of me!

[eyepeeler]

That's the kit I'm looking at running Col.