Stock GT4 setup
05-12-2016, 07:08 PM
#16
Burning Brakes
05-12-2016, 09:55 PM
#17
Instructor
05-12-2016, 10:18 PM
#18
To build on what KJ's saying (he's being very polite): Reversing the strut tops to gain more camber is a trick that works on many cars (not just Porsches). I'm not aware of it being factory documented and thus legal for any of them, though.
For that reason, if you run competitively at any big event with your strut tops reversed, you'd be risking a protest even if it's legal, because your competitors may not know. Given that, you'll definitely want to have your service manual with you.
For that reason, if you run competitively at any big event with your strut tops reversed, you'd be risking a protest even if it's legal, because your competitors may not know. Given that, you'll definitely want to have your service manual with you.
05-14-2016, 07:51 AM
#19
The GT4 (and 991 GT3) does not allow reversal of the strut top mounts. You can just loosen the bolts and slide the mount inwards within the available range.
The lower control arms in the front and back have spacers in them from the factory, and Porsche sells spacers for them. This may be the area of grayness on the GT4 (and all GT3s since first). I believe there was resolution on the GT3s at some point that it was OK to change the spacers to achieve more track and camber. Maybe someone with knowledge of that can chime in?
No longer a GT4 owner, but still interested.
The lower control arms in the front and back have spacers in them from the factory, and Porsche sells spacers for them. This may be the area of grayness on the GT4 (and all GT3s since first). I believe there was resolution on the GT3s at some point that it was OK to change the spacers to achieve more track and camber. Maybe someone with knowledge of that can chime in?
No longer a GT4 owner, but still interested.
05-14-2016, 07:34 PM
#21
Bought a Viper ACR Extreme. The car is the last of an era in my opinion and I could not resist.
GT4 was a great car. Not sure it can take out the 997 GT3s. Likely close and course dependent.
GT4 was a great car. Not sure it can take out the 997 GT3s. Likely close and course dependent.
06-10-2016, 11:53 PM
#22
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Had an alignment done by dealer. They found positive camber (!) in the left rear due to a subframe issue that, from what I gather, has a known fix from Porsche. They "adjusted subframe" to reach factory settings, then did an alignment to max camber.
-1.3 front, -1.3 rear was the max they could get (that's -1 degrees, 30 minutes), before running out of toe bolt, so the car completely maxed out camber at the factory settings.
Toe is stock (+2)' front, rear toe is +5' each wheel, which looks like half the stock setting if I read the manual right (it gives front as overall, rear as per-wheel). I could be missing this though.
-1.3 front, -1.3 rear was the max they could get (that's -1 degrees, 30 minutes), before running out of toe bolt, so the car completely maxed out camber at the factory settings.
Toe is stock (+2)' front, rear toe is +5' each wheel, which looks like half the stock setting if I read the manual right (it gives front as overall, rear as per-wheel). I could be missing this though.
06-14-2016, 02:15 PM
#23
Rennlist Member
Had an alignment done by dealer. They found positive camber (!) in the left rear due to a subframe issue that, from what I gather, has a known fix from Porsche. They "adjusted subframe" to reach factory settings, then did an alignment to max camber.
-1.3 front, -1.3 rear was the max they could get (that's -1 degrees, 30 minutes), before running out of toe bolt, so the car completely maxed out camber at the factory settings.
Toe is stock (+2)' front, rear toe is +5' each wheel, which looks like half the stock setting if I read the manual right (it gives front as overall, rear as per-wheel). I could be missing this though.
-1.3 front, -1.3 rear was the max they could get (that's -1 degrees, 30 minutes), before running out of toe bolt, so the car completely maxed out camber at the factory settings.
Toe is stock (+2)' front, rear toe is +5' each wheel, which looks like half the stock setting if I read the manual right (it gives front as overall, rear as per-wheel). I could be missing this though.
06-15-2016, 03:50 PM
#25
Had an alignment done by dealer. They found positive camber (!) in the left rear due to a subframe issue that, from what I gather, has a known fix from Porsche. They "adjusted subframe" to reach factory settings, then did an alignment to max camber.
-1.3 front, -1.3 rear was the max they could get (that's -1 degrees, 30 minutes), before running out of toe bolt, so the car completely maxed out camber at the factory settings.
Toe is stock (+2)' front, rear toe is +5' each wheel, which looks like half the stock setting if I read the manual right (it gives front as overall, rear as per-wheel). I could be missing this though.
-1.3 front, -1.3 rear was the max they could get (that's -1 degrees, 30 minutes), before running out of toe bolt, so the car completely maxed out camber at the factory settings.
Toe is stock (+2)' front, rear toe is +5' each wheel, which looks like half the stock setting if I read the manual right (it gives front as overall, rear as per-wheel). I could be missing this though.
06-15-2016, 10:39 PM
#26
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06-16-2016, 12:55 AM
#27
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The lower control arms in the front and back have spacers in them from the factory, and Porsche sells spacers for them. This may be the area of grayness on the GT4 (and all GT3s since first). I believe there was resolution on the GT3s at some point that it was OK to change the spacers to achieve more track and camber. Maybe someone with knowledge of that can chime in?
13.8 SUSPENSION
A. Standard, as defined herein, suspension springs must be used. They may not be cut, shortened, or collapsed. Spring perches may not vary from the OE shape within the working part of the perch.
B. Both the front and rear suspension may be adjusted through their designed range of adjustment by use of factory adjustment arrangements or by taking advantage of inherent manufacturing tolerances. This encompasses both alignment and ride height parameters if such adjustments are provided by the standard components and specified by the factory as normal methods of adjustment. However, no suspension part may be modified for the purpose of adjustment unless such modification is specifically authorized by the factory shop manual.
C. Suspension bushings, including but not limited to those which carry the weight of the vehicle and determine ride height, may not be replaced with bushings of a different material or dimension.
D. Replacement control arms for vehicles having integral bushing/arm assemblies must be standard manufacturer parts as per Sections 12 and 13.
E. If offered by the manufacturer for a particular model and year, the use of shims, special bolts, removal of material to enlarge mounting holes, and similar methods are allowed and the resulting alignment settings are permitted even if outside the normal specification or range of specifications recommended by the manufacturer. If enlarging mounting holes is specifically authorized but no material removal limits are specified, material removal is restricted to the amount necessary to achieve the maximum factory alignment specification.
A. Standard, as defined herein, suspension springs must be used. They may not be cut, shortened, or collapsed. Spring perches may not vary from the OE shape within the working part of the perch.
B. Both the front and rear suspension may be adjusted through their designed range of adjustment by use of factory adjustment arrangements or by taking advantage of inherent manufacturing tolerances. This encompasses both alignment and ride height parameters if such adjustments are provided by the standard components and specified by the factory as normal methods of adjustment. However, no suspension part may be modified for the purpose of adjustment unless such modification is specifically authorized by the factory shop manual.
C. Suspension bushings, including but not limited to those which carry the weight of the vehicle and determine ride height, may not be replaced with bushings of a different material or dimension.
D. Replacement control arms for vehicles having integral bushing/arm assemblies must be standard manufacturer parts as per Sections 12 and 13.
E. If offered by the manufacturer for a particular model and year, the use of shims, special bolts, removal of material to enlarge mounting holes, and similar methods are allowed and the resulting alignment settings are permitted even if outside the normal specification or range of specifications recommended by the manufacturer. If enlarging mounting holes is specifically authorized but no material removal limits are specified, material removal is restricted to the amount necessary to achieve the maximum factory alignment specification.
06-16-2016, 12:26 PM
#28
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Yes, covered under warranty, though I had to pay $$$ for them to do another alignment to try to max camber.
Stock ride height. I scrape the front on our driveway, so I really can't lower it without turning it into a trailered car.
I asked about shims at least twice. They stated that shims and all other factory changes would not result in more camber without something (e.g. aftermarket or cup part) to allow more toe adjustment. I'm not an expert, and the dealer certainly could be wrong, but this seems to be what others have said with regard to camber -- at some point you hit the limit of the threads and more camber = toe changes in addition. E.g. "For aggressive camber the stock toe bars are to short." from another thread. I just seem to have hit the limit earlier than those who can get 2 degrees or more before shims.
Stock ride height. I scrape the front on our driveway, so I really can't lower it without turning it into a trailered car.
I asked about shims at least twice. They stated that shims and all other factory changes would not result in more camber without something (e.g. aftermarket or cup part) to allow more toe adjustment. I'm not an expert, and the dealer certainly could be wrong, but this seems to be what others have said with regard to camber -- at some point you hit the limit of the threads and more camber = toe changes in addition. E.g. "For aggressive camber the stock toe bars are to short." from another thread. I just seem to have hit the limit earlier than those who can get 2 degrees or more before shims.
06-16-2016, 12:50 PM
#29
The rules on this front are rather ambiguous. The text above can be read as allowing any/all alternate shims, bolts, etc., but typically I'd expect these other rules to also apply:
From 12:
From 13:
Note that I'm not making any claim on the legality of the GT3 shims specifically, as I haven't done any research on them. My only point is that I wouldn't solely depend on the rule quoted above as proof of legality.
From 12:
standard part An item of standard or optional equipment that could have
been ordered with the car, installed on the factory production line, and
delivered through a dealer in the United States. Port-installed options
provided by the manufacturer are considered to be the same as those
installed on the factory production line. Dealer-installed options or deletions
(except as required by factory directives), no matter how common
or what their origin, are not included in this definition. This definition
does not allow the updating or backdating of parts.
been ordered with the car, installed on the factory production line, and
delivered through a dealer in the United States. Port-installed options
provided by the manufacturer are considered to be the same as those
installed on the factory production line. Dealer-installed options or deletions
(except as required by factory directives), no matter how common
or what their origin, are not included in this definition. This definition
does not allow the updating or backdating of parts.
Alternate parts listed in a factory parts manual are not authorized unless
their use is specifically referenced in the factory service manual or in a service
bulletin for the specific model.
their use is specifically referenced in the factory service manual or in a service
bulletin for the specific model.
Hardware items (nuts, bolts, etc.) may be replaced by similar items of unrestricted
origin. [...] These allowances are strictly to allow components to be replaced
from alternate sources other than the original manufacturer. They should not
be construed as an allowance to replace components with those which could
be considered a “higher performance” alternative. Parts available as replacements
through the dealers parts department, the factory, or any other source
which do not meet standard part specifications (e.g., hardness, size, etc.) are
non-compliant in Street Category, except as specifically provided elsewhere
in these rules.
origin. [...] These allowances are strictly to allow components to be replaced
from alternate sources other than the original manufacturer. They should not
be construed as an allowance to replace components with those which could
be considered a “higher performance” alternative. Parts available as replacements
through the dealers parts department, the factory, or any other source
which do not meet standard part specifications (e.g., hardness, size, etc.) are
non-compliant in Street Category, except as specifically provided elsewhere
in these rules.
06-16-2016, 10:28 PM
#30
Originally Posted by Yomi
Yes, covered under warranty, though I had to pay $$$ for them to do another alignment to try to max camber.
Stock ride height. I scrape the front on our driveway, so I really can't lower it without turning it into a trailered car.
I asked about shims at least twice. They stated that shims and all other factory changes would not result in more camber without something (e.g. aftermarket or cup part) to allow more toe adjustment. I'm not an expert, and the dealer certainly could be wrong, but this seems to be what others have said with regard to camber -- at some point you hit the limit of the threads and more camber = toe changes in addition. E.g. "For aggressive camber the stock toe bars are to short." from another thread. I just seem to have hit the limit earlier than those who can get 2 degrees or more before shims.
Stock ride height. I scrape the front on our driveway, so I really can't lower it without turning it into a trailered car.
I asked about shims at least twice. They stated that shims and all other factory changes would not result in more camber without something (e.g. aftermarket or cup part) to allow more toe adjustment. I'm not an expert, and the dealer certainly could be wrong, but this seems to be what others have said with regard to camber -- at some point you hit the limit of the threads and more camber = toe changes in addition. E.g. "For aggressive camber the stock toe bars are to short." from another thread. I just seem to have hit the limit earlier than those who can get 2 degrees or more before shims.