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Old Jul 19, 2006 | 10:53 AM
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From: Behind the wheel of a Time Attack R33 GTR
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can anybody explain whats involved with this?
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Old Jul 19, 2006 | 11:43 AM
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briefly you put all 4 wheels onto some scales then using some calculations you adjust the ride height slightly at each corner which redistributes the weight until you get a more balanced car (weight wise)
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Old Jul 19, 2006 | 11:52 AM
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gotcha....anyone know where this can be done in the herts area?
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Old Jul 19, 2006 | 12:36 PM
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Done properly this is a good adjustment to have done.
If you intend to race the car on your own then the technicial should ask you for your weight so he can compensate in the corner weights.
Quite a time consuming job to do properly.

Transformed my 911, but havn't bothered on my hill climb Impreza.

David at www.apiengines.com does it in south Warwickshire.

Graham.
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Old Jul 19, 2006 | 12:38 PM
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Graham:

Would this be a worthwhile mod at all for what you do?
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Old Jul 19, 2006 | 12:56 PM
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ill pay david a visit next month then, ill leave it for elvington as its a bloody bumpy course anyway!!
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Old Jul 19, 2006 | 07:54 PM
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I feel not really.
The Impreza shell is very accuratly made as are all modern cars. My old 911 is very very inaccurate in comparison.

I think you can set a decent set of struts to the same height on the bench and fit them to the car and align the whole chassis and the car will be pretty good.
This is what PowerStation did to mine and the way the car corners/accellerates and brakes is 'symetrical', ie a left turn feels like a right turn. It is this even feeling that cornerweighting gives you.

Cornerweighting will not dial-in a twisted chassis!

Just my opinion over 14 years of competing!

Graham
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Old Jul 19, 2006 | 08:55 PM
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that makes perfect sense actually graham, thanks for your input on this one.

I think what i may do is set the right side front 2 or 3 mm higher than the left front and the rear right 1 or 2mm higher than the left....not overly scientific....but i guess it will be more balanced that having all 4 set at the same height with a 100kg mass on the right hand side of the car.
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Old Jul 19, 2006 | 10:10 PM
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Sounds about right to me.
Graham
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Old Jul 21, 2006 | 10:20 AM
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Hiya,

A related issue is the difficulty in setting height accurately enough. On my D2 coilovers at least it takes more than a couple of bounces to find a consistent level. Not sure why this is. After a brief run, and thereafter, it's consistent. So, it takes a few iterations to get the height accurate to 1mm or thereabouts.

I suppose it's a stiction effect, but I would have thought a bounce or two would sort that?

Also, with 50/40 springs, my ability to bounce the car is a bit limited!

Andy
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Old Jul 21, 2006 | 01:44 PM
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Yes, that is all dead right Andy.
I'm not sure if hunting-down to the last 1 mm is worth it and where do you measure from?
The front wing arch on the left is possibly in a different position to the right one (manufacturing tolerances) so you need to find a spot that is true on the chassis.

This is why it is the weight on each corner that is used as body feature positions are irrellavant using weight.
The truth of the floor/scale height is also critical.

In the lte 1970 I actually designed a set of digital corner weghing platforms that were portable for McLaren!! (my only claim to 'fame')


For sure the changes it made to my 1973 911 were dramatic but those shells are everywhere which is why there are so many adjustment points on an early 911!

Graham

Last edited by 911; Jul 21, 2006 at 01:47 PM.
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Old Jul 21, 2006 | 04:21 PM
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From: Behind the wheel of a Time Attack R33 GTR
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i geuss the best course of action is simply to fit them (all the saem ride height...) drive it around for a few miles to make them settle, then find the flattest bit of road possible and wind out the drivers side a little....

Im sure ill see a massive improvement when they are all the same tbh!!
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Old Jul 21, 2006 | 05:17 PM
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Powerstation set mine on the bench to a position Curtis thought was right (from experience) and it sat flat and true straight away!
Graham
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Old Jul 21, 2006 | 09:25 PM
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Originally Posted by Neilo
i geuss the best course of action is simply to fit them (all the saem ride height...) drive it around for a few miles to make them settle, then find the flattest bit of road possible and wind out the drivers side a little....

Im sure ill see a massive improvement when they are all the same tbh!!
If you increase the height on the driver's side you will increase the weight on that corner as well as the diagonally opposite corner (depending how stiff the shell is).

Allthough impossible to guess the settings, I would expect the n/s/f to need to come up initially. Then fiddle around for ages on the scales to get it really right.

Better to set to correct ride height and forget about the scales unless you are looking for the last few tenths on a circuit or stage.

I own a set of Longacres and they only tend to come out for serious competition cars. The amount of time it takes to do it properly makes no sense for a road/semi-competition car. Especially as budget suspension (less than a grand a corner) has a lot of stiction that clouds any readings and by the time you have hit a few bumps/potholes/kerbstones, all the weights will be out again anyway.

Just my opinion............
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Old Jul 21, 2006 | 10:00 PM
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Agree!
Graham.

Last thing on your mind is cornerweights:

http://www.dropshots.com/daymainfram...0030101&cimg=0
http://www.dropshots.com/daymainfram...0030101&cimg=2

Last edited by 911; Jul 21, 2006 at 10:04 PM.
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Old Jul 21, 2006 | 10:06 PM
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From: Behind the wheel of a Time Attack R33 GTR
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that stays so flat, thats awesome

thats what i need. I think for now i will just get the car riding level and see what the guys at Mocom say when i take it for the tracking and alignment on friday.
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Old Jul 21, 2006 | 10:19 PM
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It's all in the Whiteline stuff complimenting the AST's and the Powerstation alignment.

The sum of all the parts ......(masks a crap driver too)
Bet Job is laughing at those vids!

It really is a great chassis/car just so easy to thrash!

Graham
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Old Jul 22, 2006 | 08:07 AM
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Looking good Graham.

Nice to see that you can alter the line after committing, without the car trying to send you in the scenery.

The second vid does show that it might need for some extra rebound at the front, maybe some extra low speed bump at the back, or slightly stiffer springs at the back (2 or 3 N/mm or so extra).

Cheers
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Old Jul 22, 2006 | 01:09 PM
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I'll give that a try Job, yhpm too!
Graham

Should also say sorry to the thread originator, Neilo for screwing the thread a bit, but i hope the chat is relavant...

Last edited by 911; Jul 22, 2006 at 01:55 PM.
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Old Jul 22, 2006 | 02:21 PM
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From: Behind the wheel of a Time Attack R33 GTR
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it is dont worry,...

ive just finished fitting my D2s, havent put the strut bars back on yet though as its just started to rain.

May post a few pictures later so that you can help me do a very quick set up as im not overly sure what im looking at in truth.
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Old Jul 22, 2006 | 02:37 PM
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Yes, sorry Neilo, for hijacking your thread. Can't seem to help myself :-)

In your case, set the car to your desired ride height, run the car for a week or so, to let the dampers wear in and the springs to settle. Then get a professional geometry set up done to get the wheels pointing in the right direction.

Good luck
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Old Jul 22, 2006 | 02:48 PM
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thankfully thats exactly whats happening, so im glad im doing the right thing. Its getting the geometry and alignment done this coming friday, so it will have had at least 100 miles of varied roads by then.
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Old Jul 28, 2006 | 08:57 AM
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Powerstation is now able to offer cornerweighting for £70+vat.


Andy
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Old Jul 28, 2006 | 04:57 PM
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That's good news Andy!
Graham
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