Started winter suspension upgrade
#1
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Started winter suspension upgrade
Bought this set used last February, will be installing over the next several weeks, one corner mounted.
#3
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Nice one David. What rates are you going to run?
#4
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996TT calipers
750F/600R... (turns out to be 750F/900R) these came off a well sorted 968, hopefully I will like them as is.
750F/600R... (turns out to be 750F/900R) these came off a well sorted 968, hopefully I will like them as is.
Last edited by David Floyd; 02-03-2013 at 11:12 PM. Reason: spring rate correction
#5
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Is that leaving the Torsion bar in? I'd check with the previous seller on that David. If so, what size did T/B did he run. Otherwise I think that's going to be too much front spring for the rears or too little for the fronts. As is, that's going to be very roughly 700lb f 300 r effective without T/Bar.
#7
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Is that leaving the Torsion bar in? I'd check with the previous seller on that David. If so, what size did T/B did he run. Otherwise I think that's going to be too much front spring for the rears or too little for the fronts. As is, that's going to be very roughly 700lb f 300 r effective without T/Bar.
Ha... I don't expect miracles
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#8
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Machining t-bars is not unheard of. Done in order to comply w/ racing rules that require "stock" spring types to be retained. PCA club racing rules, for example, are written this way. Coilovers can be added as helper springs, but the torsion bars technically need to be installed. In order to be in compliance w/ the rules, some guys and shops have been known to turn down the t-bars to pencil diameter to nearly eliminate their spring rate, so the rear suspension will act as if its torsion bar delete.
Of course the other legal option is to run w/ full size t-bars intact w/ the helper coilover, but then indexing is important and changing spring rates and spring lengths may be considered somewhat more complicated. And some may feel that the two spring types acting together or against each other (at certain points in the suspension travel depending on how the t-bars are indexed) is not desirable.
Or just yank the t-bars altogether, and hope a scrutineer never checks...
David, I agree that 750 front and 600 rear (w/o T-bars or w/ 10mm T-bars) is not enough rear spring (it would generate a lot of push) for what most guys prefer. Although - I have seen a huge range of what different drivers/owners will consider an "optimal" setup.
Certainly running the other way, 600 front/750 rear, would be a more balanced setup. Or 750 front/600 rear w/ full torsion bars retained would also be a more neutral setup to start with.
Of course the other legal option is to run w/ full size t-bars intact w/ the helper coilover, but then indexing is important and changing spring rates and spring lengths may be considered somewhat more complicated. And some may feel that the two spring types acting together or against each other (at certain points in the suspension travel depending on how the t-bars are indexed) is not desirable.
Or just yank the t-bars altogether, and hope a scrutineer never checks...
David, I agree that 750 front and 600 rear (w/o T-bars or w/ 10mm T-bars) is not enough rear spring (it would generate a lot of push) for what most guys prefer. Although - I have seen a huge range of what different drivers/owners will consider an "optimal" setup.
Certainly running the other way, 600 front/750 rear, would be a more balanced setup. Or 750 front/600 rear w/ full torsion bars retained would also be a more neutral setup to start with.
#9
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David,
If you are not racing PCA, then pull the t-bars. This will make setting ride height and corner balancing much easier. If you pull them, up the rear spring rate. In contrast to what many run, I do not run heavy springs in the rear.
My setup is 650 front and rear running M030 sways (275's on all corners). For me this works well and has gotten me in the 36's at Barber (which is a handling, not HP track).
If you are not racing PCA, then pull the t-bars. This will make setting ride height and corner balancing much easier. If you pull them, up the rear spring rate. In contrast to what many run, I do not run heavy springs in the rear.
My setup is 650 front and rear running M030 sways (275's on all corners). For me this works well and has gotten me in the 36's at Barber (which is a handling, not HP track).
#10
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I will delete the t-bars, found some markings engraved on the rear springs 700-888 and have a Hyperco label (Hyperco site states this is the mean rate) front springs have no markings.
M030 sways on the car now.
Thanks for the advice everyone, all help appreciated
M030 sways on the car now.
Thanks for the advice everyone, all help appreciated
Last edited by David Floyd; 01-22-2013 at 11:33 AM. Reason: more info
#11
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I emailed Hyperco about the engraved numbers, their reply was to double check the numbers to be sure as they will wear when the top hat rubs, the 2nd number is definitely 888, the 1st number was rubbed looked to be 700 is actually 900 !! so I have 900 Lb rear springs that tested at 888 lbs.
The original owner just had the numbers mixed up, I do trust what he said about being a great setup, mainly because he has close ties with Racers Edge and we know they can setup a 944.
The original owner just had the numbers mixed up, I do trust what he said about being a great setup, mainly because he has close ties with Racers Edge and we know they can setup a 944.
#12
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Both fronts mounted, now for the rear.
New Lart fuel lines installed, I think all bolts are out and ready to drop and pull t-bars, the t-bar carrier still seems very firmly in place how much force should it take to pry down the carrier ?
Urethane trans mount mod
New Lart fuel lines installed, I think all bolts are out and ready to drop and pull t-bars, the t-bar carrier still seems very firmly in place how much force should it take to pry down the carrier ?
Urethane trans mount mod
#13
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What was the previous setup David? Think you're going to notice a BIG difference if it was stock!
#15
Race Car
David, if you are dropping the torsion tube, I'd highly recommend you go ahead and change to solid mounts and Delrin spring plate bushings. I don't know what your budget situation is, but pulling hte tube is NOT something you want to do twice, and 25 year old rubber is not something you want on the track much. If you can afford to, go ahead and put in the spherical bearings on the banana arms, too. Bt that can be done later if the budget doesn't allow.
If you disconnect the axles, you'll be able to get the banana arm dropped fully out of the way. If you don't, you'll make the job ten times harder. It is actualy easier to leave it connected to the torsion tube than to leave an axle attached. Of course, if you end up pulling the tube all of the way out of the car, you'll have to disconnect it, which sn't a big deal except for having to deal with the calipers (to avoid breaking into your hydraulics).
Trust me on this, I just went through tihs on the 968, and I tried to do it like you are doing it. Got much easie when the axle was undone,a nd te banana arm dropped out of the way.
If you disconnect the axles, you'll be able to get the banana arm dropped fully out of the way. If you don't, you'll make the job ten times harder. It is actualy easier to leave it connected to the torsion tube than to leave an axle attached. Of course, if you end up pulling the tube all of the way out of the car, you'll have to disconnect it, which sn't a big deal except for having to deal with the calipers (to avoid breaking into your hydraulics).
Trust me on this, I just went through tihs on the 968, and I tried to do it like you are doing it. Got much easie when the axle was undone,a nd te banana arm dropped out of the way.