Go Back   986 Forum - for Porsche Boxster & Cayman Owners > Porsche Boxster & Cayman Forums > Boxster General Discussions

Reply
 
LinkBack Thread Tools Display Modes
Old 12-07-2011, 06:04 AM   #1
Registered User
 
Join Date: Dec 2010
Location: Hot Springs Village, Arkansas
Posts: 245
I want to stand my wheels straight up

I'm putting on new rear tires for my 2000 S. The old one are worn out on the inside because of the heavy negative camber. My main use for the car is scenic driving at moderate speeds and I'll never use the car on a track. Ultimate grip is irrelevant to how I use the car but I definitely enjoy the nimble feeling and responsiveness of the car even though I don't drive very fast.

So my question is does it hurt anything to stand the rear tires straight up? Will it make the car less nimble or responsive?

Dale_K is offline   Reply With Quote
Old 12-07-2011, 06:38 AM   #2
Ex Esso kid
 
Join Date: Dec 2005
Location: NY
Posts: 1,605
Are you asking whether you should change the suspension settings to chase some better tire wear? If so, I vote NO.
Ghostrider 310 is offline   Reply With Quote
Old 12-07-2011, 06:39 AM   #3
Registered User
 
husker boxster's Avatar
 
Join Date: Sep 2006
Location: Omaha
Posts: 2,233
When was the last time you had an alignment and how did you get the heavy negative camber? Based on your description of how you drive, normal specs would be fine. Some people have shops adjust for track use, but that shouldn't be necessary for you. Boxsters are very easy to knock out of alignment.
__________________
PCA National HPDE Instructor
2008 Boxster S Limited Edition #005
2007 Cayman S - SOLD on Valentine's Day 2013
2008 Cayman S Sport - Signal Green
husker boxster is offline   Reply With Quote
Old 12-07-2011, 07:33 AM   #4
Registered User
 
Join Date: May 2008
Location: Toronto
Posts: 2,655
You can adjust the rear camber to as neutral as it can get but the nature of the suspension geometry is designed to provide maximum grip which also means tire wear. Unfortunately you can't do much about that.
ekam is offline   Reply With Quote
Old 12-07-2011, 08:24 AM   #5
Registered Boxster abuser
 
healthservices's Avatar
 
Join Date: Oct 2011
Location: socal
Posts: 1,014
Yes you can and of course you know the compromises. There are adjustments just ask to be as close to Zero camber as possible. also check for worn out bushings
healthservices is offline   Reply With Quote
Old 12-07-2011, 08:46 AM   #6
Registered User
 
jaykay's Avatar
 
Join Date: Sep 2009
Location: toronto
Posts: 2,297
Yes you can go less negative for less tire wear on the street. I have no idea how affects your handling as its dependent upon the cornering loads you get with your type of driving. You have to feel it or get some test data or go with someone's set-up

I am trying to figure out the same thing: how to get the optimum tire contact patch for the driving I do. For me this likely means more negative camber to deal with track. cornering loads...especially on the front tires
__________________
00 986 S....with a few tweaks
jaykay is offline   Reply With Quote
Old 12-07-2011, 10:46 AM   #7
Certified Boxster Addict
 
Join Date: Nov 2010
Location: Los Angeles
Posts: 7,516
This is easy. Ask your alignment shop to set the camber as close to zero as possible. The shop will likely say that this is not within Porsche spec. Tell the shop that you understand that this is not within spec but that you want it set up this way. This will "stand up" the tire on the street and give you more even tire wear across the tire in day-to-day driving.

The downside is now when cornering hard, most of the cornering force will be placed onto the outside 1/3 of the tire rather than onto the center of the tire. This will reduce your cornering grip but won't otherwise affect the handling or ride - turn in will still be responsive, you just won't be able to corner as hard as with the stock alignment setup.

For anyone tracking their car, they want to do the exact opposite and set up the alignment with as much negative camber as possible. This will place the force on the inside of the tire during street driving but will keep the force on the center of the tire when cornering extrememly hard on the track. It is also important to set air pressures in conjuction to the alignment on the track to keep force on the center of the tire and not on the outisde 1/3 of the tire.

If you track a lot and get pretty good, you may find that you are still running more on the outside portion of the tire despite having max negative camber and proper tire pressures. The next step at this point is to either lower the car which will alter the suspension geometry in a way that increases the negative camber or install adjustable (GT-3) control arms which allow additional camber adjustment than the stock solid control arms.
__________________
1999 996 C2 - sold - bought back - sold for more
1997 Spec Boxster BSR #254
1979 911 SC
POC Licensed DE/TT Instructor
thstone is offline   Reply With Quote
Old 12-07-2011, 11:02 AM   #8
Porscheectomy
 
Join Date: Mar 2006
Location: Seattle Area
Posts: 3,011
Quote:
Originally Posted by thstone View Post
This is easy. Ask your alignment shop to set the camber as close to zero as possible. The shop will likely say that this is not within Porsche spec. Tell the shop that you understand that this is not within spec but that you want it set up this way. This will "stand up" the tire on the street and give you more even tire wear across the tire in day-to-day driving.

The downside is now when cornering hard, most of the cornering force will be placed onto the outside 1/3 of the tire rather than onto the center of the tire. This will reduce your cornering grip but won't otherwise affect the handling or ride - turn in will still be responsive, you just won't be able to corner as hard as with the stock alignment setup.

For anyone tracking their car, they want to do the exact opposite and set up the alignment with as much negative camber as possible. This will place the force on the inside of the tire during street driving but will keep the force on the center of the tire when cornering extrememly hard on the track. It is also important to set air pressures in conjuction to the alignment on the track to keep force on the center of the tire and not on the outisde 1/3 of the tire.

If you track a lot and get pretty good, you may find that you are still running more on the outside portion of the tire despite having max negative camber and proper tire pressures. The next step at this point is to either lower the car which will alter the suspension geometry in a way that increases the negative camber or install adjustable (GT-3) control arms which allow additional camber adjustment than the stock solid control arms.
There will be an added tendancy to snap oversteer.
blue2000s is offline   Reply With Quote
Old 12-07-2011, 11:43 AM   #9
Opposed to Subie Burble
 
Overdrive's Avatar
 
Join Date: Mar 2007
Location: Central CT
Posts: 1,197
Garage
The original poster specifically said he does not track the car, nor does he drive it aggressively.

If you're just going out for Sunday drives, I can't see any general everyday issues with doing what you're considering. The tires will wear more evenly but your handling will be affected. I think the only time this may be of major concern to you is when making emergency maneuvers (swerving and such) on the road.
__________________
-O/D

1997 Arctic Silver Boxster, 5-spd
IMSR + RMS
Robbins glass window top
Overdrive is offline   Reply With Quote
Old 12-07-2011, 12:30 PM   #10
Porscheectomy
 
Join Date: Mar 2006
Location: Seattle Area
Posts: 3,011
Quote:
Originally Posted by Overdrive View Post
The original poster specifically said he does not track the car, nor does he drive it aggressively.

If you're just going out for Sunday drives, I can't see any general everyday issues with doing what you're considering. The tires will wear more evenly but your handling will be affected. I think the only time this may be of major concern to you is when making emergency maneuvers (swerving and such) on the road.
Agreed, the times when you most need a warning, it won't be there
blue2000s is offline   Reply With Quote
Old 12-07-2011, 03:01 PM   #11
Registered User
 
Join Date: Jun 2005
Location: Toronto
Posts: 157
I have pretty even wear on my rear tires. I'm not sure what my alignment specs are though. I don't track the car, but do drive it as hard as I can get away with on the street and don't even begin to push the limits of the car.
I'd recommend you take it to someone who knows and is experienced with Boxster alignments and let them know your driving style and tread wear concerns and see whatthey recommend.
__________________
1997 Boxster
http://i40.tinypic.com/ax1qhz.jpg
Aron in Toronto is offline   Reply With Quote
Old 12-07-2011, 03:27 PM   #12
Registered User
 
Brucelee's Avatar
 
Join Date: Jun 2004
Location: Des Moines, IA
Posts: 8,083
I would leave it alone.
__________________
Rich Belloff

Brucelee is offline   Reply With Quote
Old 12-07-2011, 07:00 PM   #13
Registered User
 
Join Date: Dec 2009
Location: Orange County, CA
Posts: 1,269
Quote:
Originally Posted by Brucelee View Post
I would leave it alone.
+ 1...

however, if you lower the tire pressure perhaps by 2 or 3 psi, the rear tire will wear more evenly

.
Gilles is offline   Reply With Quote
Old 12-08-2011, 05:47 AM   #14
Registered User
 
Join Date: Dec 2010
Location: Hot Springs Village, Arkansas
Posts: 245
Thanks for the replies. I think I'm going to make the change to zero camber and see how it feels. I can always put it back if I don't like it. BTW, the new Kumho rear tires are very smooth & quiet.
Dale_K is offline   Reply With Quote
Old 12-08-2011, 07:17 AM   #15
Opposed to Subie Burble
 
Overdrive's Avatar
 
Join Date: Mar 2007
Location: Central CT
Posts: 1,197
Garage
Quote:
Originally Posted by blue2000s View Post
Agreed, the times when you most need a warning, it won't be there
Exactly my thinking, sir. I can appreciate the setup of the car, and the brakes, when it comes time to dodge the road-going idiots and random debris that shows up on the road. Dodging exploded semi-truck tire chunks at 70mph is never fun, and would be even less fun if the car feels like spinning and sliding.

To Dale_K, if I can make a suggestion: Though it's more involved, you can have the tires swapped from left rim to right rim for more even wear. Since our tires tend to be directional and can't be rotated by just swapping the wheels from one side to the other, this is a (more cumbersome but effective) way of accomplishing that even wear. You're still doing the same thing, getting the tire on the other side of the car, but you're doing so by removing it from one wheel and replacing in on the other.

Depending on how often you drive the car, say 5000 miles/yr or less, you could just have this done once every year and the tires will wear very evenly across the whole of the tread.
__________________
-O/D

1997 Arctic Silver Boxster, 5-spd
IMSR + RMS
Robbins glass window top
Overdrive is offline   Reply With Quote
Old 12-08-2011, 07:18 AM   #16
Ex Esso kid
 
Join Date: Dec 2005
Location: NY
Posts: 1,605
Kumho was the only tire I could find in 13" for the Fiat. Granted it is the solus, a passenger tire, but it squeals like a pig at a rodeo if you press it in as corner. The old xzx michelins didn't do that.
Ghostrider 310 is offline   Reply With Quote
Old 12-08-2011, 07:24 AM   #17
Opposed to Subie Burble
 
Overdrive's Avatar
 
Join Date: Mar 2007
Location: Central CT
Posts: 1,197
Garage
The UHP all-seasons that Kumho makes that fit the 17s on a 986 are a great deal, and I imagine their summers are even better. I wouldn't compare them to a passenger car tire. The ones I'm referring to have a great, quiet, smooth ride, and put the OEM Pirelli summers to shame in everything but grip being an all-season. The car that they're on is slowly becoming a fair weather garage queen (a shame IMO), but those tires rang in at $300 or so less, installed, than my Michelin Pilot Sports that get driven much more often, and I consider the Kumhos a very close alternative in terms of bang for buck.
__________________
-O/D

1997 Arctic Silver Boxster, 5-spd
IMSR + RMS
Robbins glass window top
Overdrive is offline   Reply With Quote
Old 12-08-2011, 07:43 AM   #18
Ex Esso kid
 
Join Date: Dec 2005
Location: NY
Posts: 1,605
They ride like bedroom slippers on the highway, I'll give them that.

Ghostrider 310 is offline   Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -8. The time now is 05:11 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page