Torsion Bar Delete
05-06-2006, 07:20 AM
#31
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Originally Posted by J Chen
Hi Dar,
Yes I do have some of it but for street Spherical Bushings &
Solid Mounts are a no no for me as the road conditions here
is not really that good.
Yes I do have some of it but for street Spherical Bushings &
Solid Mounts are a no no for me as the road conditions here
is not really that good.
05-06-2006, 08:14 AM
#32
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Yeah this is a thread from the past! I second DAR951's suggestions for the nice to haves. I first upgraded the tbs to 28mms, then pulled them completely to replace with coilovers a year later. I have the rear coilover Konis from Paragon and very happy with the 325#front springs and 425# rears on my street-only car. I like the easy adjustability in ride hight and in double adjustability, and ability to swap the not-very-expensive springs to suit conditions. This setup works great with the 968 sways for a nice tight yet adjustable ride for a street car.
Dan
Dan
05-07-2006, 12:16 AM
#33
Originally Posted by 951_VAB
Yeah this is a thread from the past! I second DAR951's suggestions for the nice to haves. I first upgraded the tbs to 28mms, then pulled them completely to replace with coilovers a year later. I have the rear coilover Konis from Paragon and very happy with the 325#front springs and 425# rears on my street-only car. I like the easy adjustability in ride hight and in double adjustability, and ability to swap the not-very-expensive springs to suit conditions. This setup works great with the 968 sways for a nice tight yet adjustable ride for a street car.
Dan
Dan
http://www.paragon-products.com/prod...rearcupkit.htm
or these?
http://www.paragon-products.com/product_p/koni_3012.htm
If your running the first set I would be interested to know if you have had any problems as these are billed as "helper" coil overs and are supposedly not to be run with out the Torsion bar. personally I think they would be just fine but since I have not even seen a set in person I would not know.
IPSC
Last edited by IPSC; 05-07-2006 at 08:10 AM.
05-07-2006, 02:56 AM
#34
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Hi 951-VAB,
You're lucky over there as the road conditions are much better.
Try driving over B grade roads & you'll understand what I mean.
Don't know if you realiize that the rear end will twist more with
coilovers installed as the total load is now handled by the upper
shock mounts & is no longer partially handled by the T-Bar Tube.
You're lucky over there as the road conditions are much better.
Try driving over B grade roads & you'll understand what I mean.
Don't know if you realiize that the rear end will twist more with
coilovers installed as the total load is now handled by the upper
shock mounts & is no longer partially handled by the T-Bar Tube.
05-07-2006, 08:33 PM
#35
Originally Posted by J Chen
Hi 951-VAB,
You're lucky over there as the road conditions are much better.
Try driving over B grade roads & you'll understand what I mean.
Don't know if you realiize that the rear end will twist more with
coilovers installed as the total load is now handled by the upper
shock mounts & is no longer partially handled by the T-Bar Tube.
You're lucky over there as the road conditions are much better.
Try driving over B grade roads & you'll understand what I mean.
Don't know if you realiize that the rear end will twist more with
coilovers installed as the total load is now handled by the upper
shock mounts & is no longer partially handled by the T-Bar Tube.
05-07-2006, 10:24 PM
#36
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I have the set in the first link, not the 3012s in the second. For me they work fine (yes our local roads are decent.) While it does say designed for use with Tbars, this set is up Jason @ Paragon suggested and has worked very well (325 front/425 rear). Definitely not the ideal for the stress of track driving but it works great on the street.
Dan
Dan
05-08-2006, 12:15 AM
#37
Originally Posted by 951_VAB
I have the set in the first link, not the 3012s in the second. For me they work fine (yes our local roads are decent.) While it does say designed for use with Tbars, this set is up Jason @ Paragon suggested and has worked very well (325 front/425 rear). Definitely not the ideal for the stress of track driving but it works great on the street.
Dan
Dan
IPSC
05-08-2006, 06:42 AM
#38
Originally Posted by J Chen
Hi HoBoJoe,
Hey hows the going man ? If you leave the torsion bars
in then you'll be using helper springs but you would have
to re-index the torsion bar. A more serious problem
which I recall reading an article years ago is that if the
preloading of the T bars & coil spring are'nt adjusted
properly, it will cause excessive oscillation which is
difficult to damp out even with custom shock.
Maybe someone can shed some light on this. As for
me, I'm running coilovers but I think for daily driven,
T bars are better suited, less noise is being transmitted
into the cabin
Hey hows the going man ? If you leave the torsion bars
in then you'll be using helper springs but you would have
to re-index the torsion bar. A more serious problem
which I recall reading an article years ago is that if the
preloading of the T bars & coil spring are'nt adjusted
properly, it will cause excessive oscillation which is
difficult to damp out even with custom shock.
Maybe someone can shed some light on this. As for
me, I'm running coilovers but I think for daily driven,
T bars are better suited, less noise is being transmitted
into the cabin
So how does one know that the t bars and coil spring are adjusted properly?
As for a full coil over setup, I don’t know.. Take a look at the shock mounts and think full compression in 150mph.. There is a lot of stress and weight that should be taken by only two "small" bolts. And what would the consequence be if one of the shock mounts snaps in those speeds..
05-08-2006, 10:49 AM
#39
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Hi Shiner,
Look closer. The torsion bar tube is a solid tube that tighs
across the chassis rails & not two individual tubes.
As I mentioned if you've got a roll cage installed it's not
a problem but if there isn't one like mine, it will for sure
twist more & also it is noiser as you go over rough suface.
Look closer. The torsion bar tube is a solid tube that tighs
across the chassis rails & not two individual tubes.
As I mentioned if you've got a roll cage installed it's not
a problem but if there isn't one like mine, it will for sure
twist more & also it is noiser as you go over rough suface.
05-08-2006, 01:22 PM
#40
Originally Posted by J Chen
Hi Shiner,
Look closer. The torsion bar tube is a solid tube that tighs
across the chassis rails & not two individual tubes.
As I mentioned if you've got a roll cage installed it's not
a problem but if there isn't one like mine, it will for sure
twist more & also it is noiser as you go over rough suface.
Look closer. The torsion bar tube is a solid tube that tighs
across the chassis rails & not two individual tubes.
As I mentioned if you've got a roll cage installed it's not
a problem but if there isn't one like mine, it will for sure
twist more & also it is noiser as you go over rough suface.
My question regarding your reference to "the rear end will twist more", was what did you mean by "twist more", and what components you were referring to. I now see that you are referring to the body flex at the upper shock mounting point. Thanks.
05-09-2006, 01:39 AM
#41
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Originally Posted by Jeremy Himsel
Has anyone noticed any ill effects when deleting the rear torsion bars and still running on the street? When you deleted the bars, did you remove them completely or did you grind off the splines and essentially leave slugs in place? Has anyone noticed a benefit (other then weight reduction) to doing it either way? I'm switching to rear coilovers and will be deleting the torsion bars in a few weeks and would appreciate any opinions.
05-09-2006, 03:13 AM
#42
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Hi Shiners,
Sorry, should have explain in detail. When using torsion bars,
all the spring load is taken up by the Torsion Tube which means
no load is pass to the upper mounts accept shock loads.
Hence less chassis twist which equals better handling on the
limit.
Sorry, should have explain in detail. When using torsion bars,
all the spring load is taken up by the Torsion Tube which means
no load is pass to the upper mounts accept shock loads.
Hence less chassis twist which equals better handling on the
limit.
05-09-2006, 08:55 AM
#43
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Originally Posted by J Chen
Hi Shiners,
Sorry, should have explain in detail. When using torsion bars,
all the spring load is taken up by the Torsion Tube which means
no load is pass to the upper mounts accept shock loads.
Hence less chassis twist which equals better handling on the
limit.
Sorry, should have explain in detail. When using torsion bars,
all the spring load is taken up by the Torsion Tube which means
no load is pass to the upper mounts accept shock loads.
Hence less chassis twist which equals better handling on the
limit.
Chris White
05-09-2006, 09:07 AM
#44
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OK, seems I have posted on this many moons ago….but what the hell, lets go over it again!
If you are concerned about the failure of the upper mount when going full coil over keep in mind that the simplistic approach of static loading doesn’t have anything to do with the real world.
In the 150 mph scenario that was mentioned the shock mount sees almost the same momentary load in the coil over as the stock set up. The vast majority of any transient impulse (bump
) is absorbed via the shock and the load is transmitted to the upper mount.
The stock spring rate is fairly low – lets say 150 lb/inch for the sake of easy math – that means an impulse of 600 lbs of force would deflect the stock suspension by 4” – but in reality it will only deflect by 1” – the majority of the impulse was absorbed/transmitted by the shock to the upper mount.
I have been running full coil overs for 4 years or so for street/track use. I replaced the stock rubber Tbar bushing last year with a Delrin version as a precaution – the old rubber one was fine with no deformation.
Conclusion – if you are worried about the upper mount pay more attention to force transmitted by the shock compression setting than the spring loading.
Chris White
If you are concerned about the failure of the upper mount when going full coil over keep in mind that the simplistic approach of static loading doesn’t have anything to do with the real world.
In the 150 mph scenario that was mentioned the shock mount sees almost the same momentary load in the coil over as the stock set up. The vast majority of any transient impulse (bump
) is absorbed via the shock and the load is transmitted to the upper mount. The stock spring rate is fairly low – lets say 150 lb/inch for the sake of easy math – that means an impulse of 600 lbs of force would deflect the stock suspension by 4” – but in reality it will only deflect by 1” – the majority of the impulse was absorbed/transmitted by the shock to the upper mount.
I have been running full coil overs for 4 years or so for street/track use. I replaced the stock rubber Tbar bushing last year with a Delrin version as a precaution – the old rubber one was fine with no deformation.
Conclusion – if you are worried about the upper mount pay more attention to force transmitted by the shock compression setting than the spring loading.
Chris White
