Fury Suspension play
Discussion
Here goes nothing.
My Fury has a live axle and I have noticed that the car doesnt feel particularly tied to the road. Under hard acceleration it feels slightly alarming. Its much better on a track.
I think the dampers are set quite soft and I havnt been able to free them off yet to dial a bit more bump and rebound on. They'll be coming off next weekend to try and free them off.
However the main problem seems to be that if I stand in the car and jump up and down there is a knocking. If I grab the roll bar and pull the car from side to side again the knocking can be felt. Jacking it up the main pivot of the nearside trailing arm had lateral play of about 1/2 inch. I ordered a new metalastic bush for it and went to fit it. However the old one wasnt worn. It seems that the frame was too wide for the trailing arm. So I have packed it out with an additional washer making sure that it fits the bushing. The other side seems ok. I have eliminated the play there. But the knocking has barely got better. The pivot bolt was also smaller than the bushing but I wasnt sure how much difference that would make. I can't detect any play anywhere else. I thought the Panhard Rod would have some play, but the previous owner rebushed that already. I cant see any other play. It seemed like it might becomeing from the axle or wheel bearing but it isn't. I have been advised that it is nothing to worry about. But I cant help feeling that it is something to worry about.
I appreciate that it is quite hard to give any advice in the absense of any pictures so here are a few.
Thanks guys
My Fury has a live axle and I have noticed that the car doesnt feel particularly tied to the road. Under hard acceleration it feels slightly alarming. Its much better on a track.
I think the dampers are set quite soft and I havnt been able to free them off yet to dial a bit more bump and rebound on. They'll be coming off next weekend to try and free them off.
However the main problem seems to be that if I stand in the car and jump up and down there is a knocking. If I grab the roll bar and pull the car from side to side again the knocking can be felt. Jacking it up the main pivot of the nearside trailing arm had lateral play of about 1/2 inch. I ordered a new metalastic bush for it and went to fit it. However the old one wasnt worn. It seems that the frame was too wide for the trailing arm. So I have packed it out with an additional washer making sure that it fits the bushing. The other side seems ok. I have eliminated the play there. But the knocking has barely got better. The pivot bolt was also smaller than the bushing but I wasnt sure how much difference that would make. I can't detect any play anywhere else. I thought the Panhard Rod would have some play, but the previous owner rebushed that already. I cant see any other play. It seemed like it might becomeing from the axle or wheel bearing but it isn't. I have been advised that it is nothing to worry about. But I cant help feeling that it is something to worry about.
I appreciate that it is quite hard to give any advice in the absense of any pictures so here are a few.
Thanks guys
I had a few knocks from my live axle Furyblade. The length adjuster on the panhard rod would come loose and knock, likewise the bolt on the end behind the passenger seat would loosen and knock. And the differential / driveshafts would knock when you rocked the car. If in doubt take it to a Fisher specialist or an RGB racer to check it over. Also remember the metallastic bushes should only be fully tightened when the car is on the ground and fully weighted up. A friend who was a tasty wheelman and FFord racer could not explain why his Furyblade suddenly did not handle like it used to after some work was carried out. Nobody else could explain why or could tell the car was not perfect, but he knew and persisted. After lots of money was spent, he found out somebody had tightened all the metalastic bushes while the car was in the air on a 4-post ramp. Come to think of it, I think there was some clonking from that lot too! And check all the diff bolts are tight, and that there is no cracks on ALL the rear chassis mounts. If in doubt, do not drive it.
Furyblade_Lee said:
The length adjuster on the panhard rod would come loose and knock...
Lateral control of the axle is dealt with by the Panhard rod, so if there's enough sideways play (or incorrect clearance) to allow the trailing arms to knock against the chassis, the Panhard would be first suspect... either the bushes are shagged or it's the wrong length (or both...).eta... Whereabouts in the country are you? There maybe someone close enough to give you a second opinion (or at least to yank on your roll bar while you lie on the floor and try to decide where the noise is coming from
)Edited by Sam_68 on Monday 15th February 21:43
Roll under the car and grab all your trailing arms, Panhard rod etc, one by one, and give them a damn good push and pull, in all directions.
Any movement you feel is too much movement and will echo through the body. There should be no play in Metalastic bushes, as it means they are worn out, torn, or the clamping bolt is loose, and will break eventually.
The clamping bolt should securely lock the bush inner tube in place, if not, then it is pointless having Metalastic bushes in there in the first place.
Any movement you feel is too much movement and will echo through the body. There should be no play in Metalastic bushes, as it means they are worn out, torn, or the clamping bolt is loose, and will break eventually.
The clamping bolt should securely lock the bush inner tube in place, if not, then it is pointless having Metalastic bushes in there in the first place.
Thanks for the replies. I am based around the West Midlands area.
I have pulled and pushed everything there seems to be no additional play nopw that I've fixed the other trailing arm. Panhard rod seems fine. It does get close teh exhaust and I caught my fingers in there as my Father jumped up and down in the car...ouch.
I'm taking the Dampers off this weekend hopefully and I'll have another look then. I havnt seen any cracks anywhere.
I have a few track days lined up this year. First one is Silverstone on the 19th March. So want to get it sorted soonish
I have pulled and pushed everything there seems to be no additional play nopw that I've fixed the other trailing arm. Panhard rod seems fine. It does get close teh exhaust and I caught my fingers in there as my Father jumped up and down in the car...ouch.
I'm taking the Dampers off this weekend hopefully and I'll have another look then. I havnt seen any cracks anywhere.
I have a few track days lined up this year. First one is Silverstone on the 19th March. So want to get it sorted soonish
Edited by Crippo on Tuesday 16th February 12:01
What are peoples thoughts on poly bushes compared to metalastic bushes. On my Mojo one of the bushes has worn out quicker than the others. I am currently looking at modifying the suspension arm to stop this from happening again. Once modified I do not know if I should stick with metalastic bushes or change to poly bushes. Just wondered what peoples thoughts are? The car is mainly used for trackdays
Sorry for hijacking the thread....
Cheers
Andy
there is an artivcle written from Sam about metalastic bushes..try the "search" option.
your suspension play could be the following:
fisher produced a series of kits/cars where the hole in the fixing brackets for the trailing arms only "allowed" to use 3/8" bolts, whereas the inner sleeve of the metallastic bushes is made for a 1/2"bolt. ergo: play.
when the cars had been built the owners tightend the nuts and squeezed the u-shaped fixing brackets...ergo: no play. but this was the wrong method.
over the years the play returned.
thats your problem!!
www.antivibrationmethodsrubber.co.uk/html/torsion_...
ths is the type you need: BP636/2
you need to enlarge the holes in the chassis to allow using the correct 1/2" bolts.
your suspension play could be the following:
fisher produced a series of kits/cars where the hole in the fixing brackets for the trailing arms only "allowed" to use 3/8" bolts, whereas the inner sleeve of the metallastic bushes is made for a 1/2"bolt. ergo: play.
when the cars had been built the owners tightend the nuts and squeezed the u-shaped fixing brackets...ergo: no play. but this was the wrong method.
over the years the play returned.
thats your problem!!
www.antivibrationmethodsrubber.co.uk/html/torsion_...
ths is the type you need: BP636/2
you need to enlarge the holes in the chassis to allow using the correct 1/2" bolts.
Edited by Comadis on Wednesday 17th February 20:47
Comadis said:
there is an article written from Sam about metalastic bushes..
Who? Me? 
I'm damned if I can remember writing an article about that, but then the old memory is playing up, these days!
I've probably said at some stage that fully poly-bushing or Rose jointing a live axle Sylva is a bad idea, 'cos the longitudinal Watts linkages rely on some compliance from the rubber buses to work correctly (and indeed the bushes effectively work to increase roll resistance to some degree), but the Mojo uses a completely different arrangement so the same considerations don't apply.
Personally, I'm still not a huge fan of poly bushes; as a general rule I'd say that that if you want compliance use rubber and if you want precision use rose joints (but be ready to replace them regularly), 'cos polybushes can just sometimes just give you the worst of both worlds, but I guess that for some people (or in some situations), they might be the right compromise between the two.
Comadis said:
there is an artivcle written from Sam about metalastic bushes..try the "search" option.
your suspension play could be the following:
fisher produced a series of kits/cars where the hole in the fixing brackets for the trailing arms only "allowed" to use 3/8" bolts, whereas the inner sleeve of the metallastic bushes is made for a 1/2"bolt. ergo: play.
when the cars had been built the owners tightend the nuts and squeezed the u-shaped fixing brackets...ergo: no play. but this was the wrong method.
But you have to tighten down onto the compression tune in the middle of the bush, otherwise you will be pivoting on the loose steel tube, steel on steel. There will be clearance between the bolt diameter and the compression tube, and the clamping action is all that stops it moving. your suspension play could be the following:
fisher produced a series of kits/cars where the hole in the fixing brackets for the trailing arms only "allowed" to use 3/8" bolts, whereas the inner sleeve of the metallastic bushes is made for a 1/2"bolt. ergo: play.
when the cars had been built the owners tightend the nuts and squeezed the u-shaped fixing brackets...ergo: no play. but this was the wrong method.
Same with poly bushes, you need to torque down and clamp the compression tube.
metalastic bushes and polybushes work complete different. therefore the tightening process is also a bit different.
on the metalstic there should be not much play between the chassis brackets and the sleeve (only so much that you can insert the trailing arm,incl. bush between the brackets. also keep in mind that the inner sleeve is always a bit longer than the bush. if you have more play using spacers is a MUST!! if you clamp the chassis brackets by force to eliminate the play, the brackets will not stay parallel therefore dont clamp the inner sleeve properly.
you need to put the car back on the wheels (under its own load) b4 tightening the bolts with the requested torque.
once tightened the brackets clamp the inner of the bush to the chassis, allowing the rubber to flex under the weight of the car.
polybushes do not flex under load, they rotate on the bolt or the sleeve rotates in the bushes.
on the metalstic there should be not much play between the chassis brackets and the sleeve (only so much that you can insert the trailing arm,incl. bush between the brackets. also keep in mind that the inner sleeve is always a bit longer than the bush. if you have more play using spacers is a MUST!! if you clamp the chassis brackets by force to eliminate the play, the brackets will not stay parallel therefore dont clamp the inner sleeve properly.
you need to put the car back on the wheels (under its own load) b4 tightening the bolts with the requested torque.
once tightened the brackets clamp the inner of the bush to the chassis, allowing the rubber to flex under the weight of the car.
polybushes do not flex under load, they rotate on the bolt or the sleeve rotates in the bushes.
Edited by Comadis on Sunday 21st February 13:05
Edited by Comadis on Sunday 21st February 13:09
Comadis said:
polybushes do not flex under load, they rotate on the bolt or the sleeve rotates in the bushes.
NO! A polybush must NEVER rotate on the bolt. There is a "crush tube" just like a metalastic bush which must be firmly clamped in the suspension bracket. A bolt is a fixing, not a bearing surface.The problem with the mismatched hole sizes (and I'm almost certain it wasn't Sam that posted about this) shouldn't give excess play if the bolt has been sufficiently tightened, but what it would do is give very unrepeatable suspension geometry every time it was re-assembled.
as i said, the polybushes rotate on the sleeve OR the bolt.
so if the sleeve is firmly tightened between the chassis brackets it happens on most polybush constructions that the bush will rotate on the sleeve.
it shouldnt, but it does.
anyway: the wrong hole diamter in the chassis brackets on some furys is a factory mistake, which has been confirmed as a mistake by Fisher and BGH.
so if the sleeve is firmly tightened between the chassis brackets it happens on most polybush constructions that the bush will rotate on the sleeve.
it shouldnt, but it does.
anyway: the wrong hole diamter in the chassis brackets on some furys is a factory mistake, which has been confirmed as a mistake by Fisher and BGH.
i dont know a huge amount about this but i have a stylus and i have replaced most of my suspension components.
Just a quick question, is the car on the ground in the second photo above? if so the panhard looks at the wrong angle, i understood it needs to be as horizontal as possible. I moved the mounting point on my chassis for the p/hard rod so it was 30mm lower than stock. Being at that angle when the car is on its wheels would cause more lateral movement than it should have and possible knocks the trailing arms on the chassis or seat tub.
I also rose jointed the chassis end of my arms and my p/hard rod. The axle ends are poly bushed. I love the way the rear of mine behaves on the track or the road, its so predictatble, is the front i cant seem to get right and thats stock other than rose jointed wishbones but its no different to when it was bushed, although its great on track, its just a bit twitchy on uneven roads. !
Just a quick question, is the car on the ground in the second photo above? if so the panhard looks at the wrong angle, i understood it needs to be as horizontal as possible. I moved the mounting point on my chassis for the p/hard rod so it was 30mm lower than stock. Being at that angle when the car is on its wheels would cause more lateral movement than it should have and possible knocks the trailing arms on the chassis or seat tub.
I also rose jointed the chassis end of my arms and my p/hard rod. The axle ends are poly bushed. I love the way the rear of mine behaves on the track or the road, its so predictatble, is the front i cant seem to get right and thats stock other than rose jointed wishbones but its no different to when it was bushed, although its great on track, its just a bit twitchy on uneven roads. !
1.
.....the rear suspension on a live axle Sylva does not work if fully Rose jointed - the rubber bushes are necessary to give enough compliance for the axle to function correctly in roll. It's designed to add to roll stiffness. It does rely on being rubber bushed to work properly, though; the only failures I've heard of personally are where people have misunderstood how the system operates and have rose-jointed the links.
the Sylva rear linkages are capable of more than enough roll movement (the chassis would ground before the suspension ran out of roll compliance), provided you leave the rubber bushes in the suspension as it was designed to work.
2.
If it's a live axle car, make sure the rear suspensionhas been built correctly, using rubber bushes and big fail-safe washers between the bush and the retaining bolt. A lot of people mistakenly fit Rose joints or nylon bushes, failing to realise that the linkages put torsional loads into the axle under roll. These result in very high wear on nylon bushes, or potential cracking at the suspension mountings if Rose joints are used. You can get away with partial Rose jointing, so long as there's at least one rubber bush on each linkage arm, but I don't think there's much advantage in it, so I can't see the point. And even on fully rubber bushed cars, I've known the bolt pull through the bush on the Panhard rod (which gives interesting handling characteristics), hence the need for washers as a fail-safe.
some of this was woirtten by sam68 over here: http://www.pistonheads.com/GASSING/topic.asp?h=0&a...
and i must agree!!
.....the rear suspension on a live axle Sylva does not work if fully Rose jointed - the rubber bushes are necessary to give enough compliance for the axle to function correctly in roll. It's designed to add to roll stiffness. It does rely on being rubber bushed to work properly, though; the only failures I've heard of personally are where people have misunderstood how the system operates and have rose-jointed the links.
the Sylva rear linkages are capable of more than enough roll movement (the chassis would ground before the suspension ran out of roll compliance), provided you leave the rubber bushes in the suspension as it was designed to work.
2.
If it's a live axle car, make sure the rear suspensionhas been built correctly, using rubber bushes and big fail-safe washers between the bush and the retaining bolt. A lot of people mistakenly fit Rose joints or nylon bushes, failing to realise that the linkages put torsional loads into the axle under roll. These result in very high wear on nylon bushes, or potential cracking at the suspension mountings if Rose joints are used. You can get away with partial Rose jointing, so long as there's at least one rubber bush on each linkage arm, but I don't think there's much advantage in it, so I can't see the point. And even on fully rubber bushed cars, I've known the bolt pull through the bush on the Panhard rod (which gives interesting handling characteristics), hence the need for washers as a fail-safe.
some of this was woirtten by sam68 over here: http://www.pistonheads.com/GASSING/topic.asp?h=0&a...
and i must agree!!
Comadis said:
as i said, the polybushes rotate on the sleeve OR the bolt.
so if the sleeve is firmly tightened between the chassis brackets it happens on most polybush constructions that the bush will rotate on the sleeve.
it shouldnt, but it does.
The poly bush is meant to rotate on the inner sleeve, unlike the rubber Metalastic that flexes rather than slips.so if the sleeve is firmly tightened between the chassis brackets it happens on most polybush constructions that the bush will rotate on the sleeve.
it shouldnt, but it does.
The thing I have found with poly hush set-ups is that they are often too tight, and when installed and clamped down tight the poly compresses so much the joint is almost solid. They should be measured and given clearance of about 0.010" on the ends after assembly.
The set up on my hot rod four bar had the poly bushes about 020" too long, and lacking access to a lathe I rigged up this device for trimming a touch off the ends. I dot punched the outside of the sleeve to make the bush grip, used a fresh flap disc, and a couple hundred rpm on the drill, and all was well with the world.
Hi
First off just because it's a live axle dose not mean it will inherently be twitchy. Thats just a people who have no understanding of dampers and springs and unsprung weight. The common problem is that as the metalastic bushes reach a few years old there is just not enough compliance left in them to allow the poor desighn to work correctly. First step however is to check all suspension brackets for separation or cracking. It is usually the rear ones that depart company from the chassis first.
Virtually all of the Sylvia cars are equipped with 1/2" diameter bushes and then 12mm bolts. This dose lead to quite a bit of movement on the rear suspension. And as many owners have had to do replacing the bolts and enlarging of the chassis brackets is necessary. Also in 99% of scenarios the dampers simply are not valved to work with a live axle setup so having the dampers checked on a dyno is also one of the biggest areas where improvements are found.
First off just because it's a live axle dose not mean it will inherently be twitchy. Thats just a people who have no understanding of dampers and springs and unsprung weight. The common problem is that as the metalastic bushes reach a few years old there is just not enough compliance left in them to allow the poor desighn to work correctly. First step however is to check all suspension brackets for separation or cracking. It is usually the rear ones that depart company from the chassis first.
Virtually all of the Sylvia cars are equipped with 1/2" diameter bushes and then 12mm bolts. This dose lead to quite a bit of movement on the rear suspension. And as many owners have had to do replacing the bolts and enlarging of the chassis brackets is necessary. Also in 99% of scenarios the dampers simply are not valved to work with a live axle setup so having the dampers checked on a dyno is also one of the biggest areas where improvements are found.
procomp said:
Hi
First off just because it's a live axle dose not mean it will inherently be twitchy. Thats just a people who have no understanding of dampers and springs and unsprung weight.
They probably have no understanding of basic physics either! First off just because it's a live axle dose not mean it will inherently be twitchy. Thats just a people who have no understanding of dampers and springs and unsprung weight.
Edited by singlecoil on Monday 1st March 16:51
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