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Thread: 944 Rear Camber Adjustment

  1. #1
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    Default 944 Rear Camber Adjustment

    In Jon Milledge's 944 Organizer, he says that independent camber adjsutment can be achieved by "Late rear crossmember for adjustable eccentric system welded to pickup points." I am not sure what this means, anybody got any idea?

    I spent far too many hours recently setting and resetting toe and camber and it's still not dead-on.

    timo
    timo

  2. #2
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    Sounds like you need more practice!

    I don't know what this is talking about, unless he's referring to some possibly not-IT-Legal mods. Will have to take a look, believe I have that guide around here somewhere...

    For comparison, what tools are you using to set camber and toe? Do you have the magic P221 tool for rear toe adjustment? Do you have a camber gauge that will read with the car in the air??

    I always set the rear of the car on jackstands, wheels still on. I wait for the shock to settle - sometimes apply a bit of downward pressure on the tire to be sure - very important - then measure where the camber is at. Then make the incremental adjustment, drop and bounce the car, roll it out well, and we're usually good. Note also that camber can transfer a little bit side to side, and so you don't always get the same result as in the air. Sometimes it's better to go a little less than you think you need, if it's more than 1/4 of a degree to go.

    So, say the car's at 2.5 deg on the ground, and I want 2.75. I'll put it up on jackstands (rear only is fine), push the tire down. Then I'll measure something like, 1/4 neg camber in the air (typically). So I'll move it to 1/2 deg neg camber, drop, roll and remeasure. But if it's off 1 degree - I might only move it... say from 1/4 up to 1 deg even, adding only 3/4 deg neg camber - cause it might in fact overshoot a little.

    It is a PITA system, but once you get it set right, it does work very very well...
    Vaughan Scott
    Detroit Region #280052
    '79 924 #77 ITB
    #65 Hidari Firefly P2
    www.vaughanscott.com

  3. #3
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    Well, I have heard of that, in some posts in the past. If I understand correctly, it goes in the empty slot between the camber adjustment bolt (where the sway bar is mounted) and the two slotted bolts? At $35 from Paragon it might be a good idea.

    - Is this also used to stabilize the rear suspension while the camber is adjusted?

    As far as measuring camber, I generally only lift ine side of the car at a time, then do something similar to your method, albeit at abot 8 deg. I use an angled piexce of metal. The problem is, I loosen all three nuts (camber + 2 x toe) to adjust it and when it all goes back together it's a mystery! I think my methodology is in need of improvement.

    The other problem I encounter is that whenever I loosen the nuts enought to allow movement of the spring plate and control arm, everythign shifts in one big go and I've already lost my startong poing (even if I mark everything before hand). Maybe jacking the car on both sides would help that?

    - Do you jack by the transmission?
    - Do you care to share a good value for rear toe? I have been running about 1-2mm toe-in on each side (total of about 3mm, or 1/8" total). This is measured on the wheel rims on 15" wheels, level with the axle stub.
    timo

  4. #4
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    Yeah, if you don't have that tool, you're gonna have a HELLUVA time trying to set things. Not impossible, but so difficult as to not be worth saving the $35.

    Otherwise you have motion in two axes of freedom, and are only controlling one of those.

    I only loosen the 3 bolts BARELY enough to be able to move things. Best is to have a competent helper continuously monitoring the camber while you're under the car adjusting. Same deal with rear ride height adjustment (you ARE scaling/have scaled the car, aren't you???).

    I do jack by the trans, yes, and jackstands under the torsion bar ends while adjusting.

    Your toe-in is exactly what I use, 1/8" total. That with usually 2.75-3.0 deg rear camber (depending on how much grip I need vs. tire longevity - 2.75 is better for even tire wear, but 3 has a small advantage in cornering grip I think).
    Vaughan Scott
    Detroit Region #280052
    '79 924 #77 ITB
    #65 Hidari Firefly P2
    www.vaughanscott.com

  5. #5
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    Excellent. I'll call Paragon asap!

    Yes I am scaling, but my scales suck - it's a proportional (read: cheap) system, uses bathroom scales. I need to upgrade, I know. But I do scale the car first. It's pretty repeatable and I've tried moving the scales after to make sure I get the same result. I'm within 1% cross weight and about 51.5% up front.

    Thanks for the advice. Now all I need is a competent helper (I have an enthusiastic 2-year old, but enthusiasm and competence don't necessarily go hand-in-hand!)
    timo

  6. #6
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    Cheaper is way better than nothing!!! Sucks trying to drive a car when the cross-weight's 5% in the wrong direction!!!

    I'm surprised to see such a front weight bias... what's the story there? All the 924's/944's I've done tend to be 1-2% biased to the rear. Do you have no gas in it? Or too much rake?

    Feel free to shoot me more questions as needed... I've been racing and doing my own alignments and cornerbalancing on these cars for going on 10years now...
    Vaughan Scott
    Detroit Region #280052
    '79 924 #77 ITB
    #65 Hidari Firefly P2
    www.vaughanscott.com

  7. #7
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    This car has always had fron bias - in fact both of my cars have. The car is an '88 and the old one was '86. Maybe an '83 is different?

    The ride height is set to 5 inches at the rear and 5-1/4" at teh front, so there is ride-height bias to the back. It's a little more on the right...

    BTW had a good race at Road Atlanta last weekend. Finshed 3rd out of 12 cars from a 7th place start. The handling was excellent save a little too much understeer. I like the new R6 tires (new for me anyway).
    timo

  8. #8
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    Well, level that puppy out front/rear, that should help a little with the understeer! Your choice if you raise the front or lower the rear. I usually run about 5 1/4" front, 5.5" rear for a little rake for a little more downforce at speed.

    If it's understeering now, it's only gonna get worse with old tires! What're your bars and spring rates like??
    Vaughan Scott
    Detroit Region #280052
    '79 924 #77 ITB
    #65 Hidari Firefly P2
    www.vaughanscott.com

  9. #9
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    Well let me see if I can remember... 32mm torsion bars, I know that. I think the springs are 550 lb. or so.

    Sway bars are the (heavy) Kokeln, set to minimum on front and and 40% on rear. I inched up the rear bar a little and need to inch it more. I also have Advance Design shocks, all set to 50%.

    I'd like to make some nice NASCAR style bars - researched all the right bits, and it would be very light, but it is a matter of time...I have very little!!!

    I recently read that 50% front/rear bias is not good - a car should always be set up with at least 1% to the front or rear. I think this was in Skip Barbers book, or maybe somewhere else. 50% would make the car unstable.
    timo

  10. #10
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    Yeah, that's a bit too strong on the front spring, generally, for such rear bars. For reference, I run 34mm rear bars, and have been giving thought to 550's up front. 500's would probably be preferable for you; I'm running 600's currently and the car's had just a bit more understeer/lack of turn-in than optimal (though we're also really getting into the zone where we need more shock tuning).
    Vaughan Scott
    Detroit Region #280052
    '79 924 #77 ITB
    #65 Hidari Firefly P2
    www.vaughanscott.com

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