|
|
|
|
| Author |
|
|
Registered
Join Date: Feb 2006
Location: Hong Kong -
Posts: 527
|
3.2 Tire Pressure
Just checked the PSi in my Bridgestone SO2 tires on the rear of my 89 3.2 coupe. Have driven just over 100 miles since buying the car swith 36 PSi so still getting a feel for them.
When having the pressure checked today at the garage had the rear tires filled to 44 psi per the manual, although a check of the PSI in the rear tires then revealed they were at 36 Psi. The car seems to float a bit now in the rear, of course the ride is a bit harsher (which would be expected). Might play with the rear pressure a bit and was wondering what others have found regarding this. Do only recreational spirited driving in dry conditions only. Thanks. Front remains the same at 29 PSI 
__________________
Euro 1989 Carrera 3.2 Paint Code L 693 Stone Grey 45,000 kms logged Last edited by Rad Hatter; 03-25-2006 at 06:51 AM.. |
||
03-25-2006, 05:05 AM
|
|
|
Recreational User
Join Date: Mar 2004
Location: A Mile High
Posts: 4,159
|
Disregard the manual's specification of 44 psi for the rear. It's a typo! 36 psi is correct for the rear, which you can also find on one of the metal decals in the engine compartment.
 
Last edited by porschenut; 03-25-2006 at 07:29 AM.. |
||
|
03-25-2006, 07:25 AM
|
|
|
Registered
Join Date: Feb 2006
Location: Hong Kong -
Posts: 527
|
wow great stuff ...many thanks Dave
__________________
Euro 1989 Carrera 3.2 Paint Code L 693 Stone Grey 45,000 kms logged |
||
|
03-25-2006, 07:30 AM
|
|
|
Registered
Join Date: Dec 2005
Location: Austin TX USA
Posts: 167
|
36
Yep, 36 psi rear is correct, 44 is a typo. The PO of my car did not read that and ran the rear tires at 44. I guess it didn't hurt anything. Great looking car by the way.
__________________
'86 911 Sunroof Coupe '91 Miata '77 BMW R75/7 |
||
|
03-25-2006, 07:30 AM
|
|
|
Registered
|
What is your Tire size??
29/36 is for 6/7 Front and 7/8 rear (15" or 16") I think the Turbo or Turbolook with 7" front and 9"/16 rear has 29/44 so it depends on your tire size... jo |
||
|
03-26-2006, 03:07 AM
|
|
|
Registered
Join Date: Aug 2002
Location: Galivants Ferry, SC
Posts: 10,550
|
44 is absurd for any Porsche...especially since these are "cold" pressures and will increase 6 psi when "hot" ..... might as well be running bicycle tires for all the contact patch you'll have...
Wil
__________________
Wil Ferch 85 Carrera ( gone, but not forgotten ) |
||
|
03-26-2006, 05:13 AM
|
|
|
|
Registered
Join Date: Mar 2005
Location: Melbourne, Australia
Posts: 546
|
I would suggest you play around a little. The 6-7 pound difference in the manual is designed to build in understeer for "safety".
2-4 psi difference is worth checking out. Simon
__________________
85' Carrera 3.2 02' Mazda MX5 |
||
|
03-27-2006, 01:31 AM
|
|
|
Registered
|
Quote:
Hi Wil, maybe its absurd..i use a bit less anyway, but its definitly what Porsche said.  911 6J / 7J / 8J x 15 or 16 and all the old ones 29 front 36 rear but for 930 and Turbolook models with 7J x16 and 9J x16 rear its 29 front and 44 rear. For the 930 Turbo S - 36PSI front!! I dont know if it only depends on the higher weight or in the tire size: But its a fact and no typo error: 2,0 bar = 29 PSI 2,5 bar = 36PSI 3,0 bar = 44PSI Vorderachse= front Hinterachse=rear its also on the decal (engine bay), take a look on a 930. (or here: http://www.carclassic.biz/picturepages/porsche23.htm ) I runs definitly better with less than 44PSI on 9J X 16 and 36PSI is never totaly wrong  Jo Last edited by exponence; 03-27-2006 at 01:47 PM.. |
||
|
03-27-2006, 01:33 PM
|
|
|
Back in the saddle again
Join Date: Oct 2001
Location: Central TX west of Houston
Posts: 56,219
|
Lots of people have good luck with 32/34
__________________
Steve '08 Boxster RS60 Spyder #0099/1960 - never named a car before, but this is Charlotte. '88 targa  SOLD 2004 - gone but not forgotten
|
||
|
03-27-2006, 01:40 PM
|
|
|
Registered
Join Date: Feb 2006
Posts: 9
|
My mechanic has suggested 34/40 front/rear for my 85 Carrera. I have 205/50/17 and 255/40/17.
|
||
|
03-27-2006, 01:53 PM
|
|
|
Registered
|
I run 36 for the rear and 32 for the front
__________________
Howard 2003 996tt 1997 911 Coupe Artic Silver (sold) 1988 Black 911 Coupe (gone but not forgetten) |
||
|
03-28-2006, 08:24 AM
|
|
|
Registered
Join Date: Mar 2004
Location: S.E. Pennsylvania
Posts: 1,967
|
While the "recommended" tire pressues for my Carrera is 29 F, 36 R, I've got to believe that pressure was relevant to the tire technology at the time.
My car was delivered with Dunlop D40M2's on 6J/7J's on 16's, that was 19 - 20 years ago. Every service shop I've ever been to, recommended a higher pressures in front tires but still maintained that 36 R was adequate.
__________________
The Fox Carrera |
||
|
03-28-2006, 08:51 AM
|
|
|
coolcavaracing.com
|
So, 2,5bar/36PSI front & 3,0bar/44PSI rear??
__________________
Pål (Paul) - The Norwegian lost in Finland... 1978 911SC 3.6 | 2001 Boxster S Racing Car | 1966 912 based 911 RSR replica racing car (for sale!) come and follow the Porsche Sports Cup racing fun and me at www.facebook.com/coolcavaracing 
|
||
|
03-28-2006, 10:43 AM
|
|
|
Friend of Warren
Join Date: Oct 2000
Location: Lincoln, NE
Posts: 16,496
|
For anyone I would suggest you start with the recommended pressures of 29 front/36 rear and see how the car feels. After that move up and down a couple of pounds at a time and see if the car steers better or worse. Don't rely on what others are doing or have done. Each car/tire set up is different.
__________________
Kurt V No more Porsches, but a revolving number of motorcycles. |
||
|
03-28-2006, 10:49 AM
|
|
|
Registered
|
Quote:
The 930 is also different, but what Kurt said is correct... 29 front / 36 rear...that is never totaly wrong.. the rest is............ Jo |
||
|
04-06-2006, 01:19 PM
|
|
|
Registered
Join Date: Aug 2002
Location: Galivants Ferry, SC
Posts: 10,550
|
Or maybe Kroggers is obliquely asking the bar vs psi relationship...
In that case...yes, since 1 bar = 14.5 psi - Wil
__________________
Wil Ferch 85 Carrera ( gone, but not forgotten ) |
||
|
04-07-2006, 06:19 AM
|
|
|
coolcavaracing.com
|
Yes, thank you Wil
__________________
Pål (Paul) - The Norwegian lost in Finland... 1978 911SC 3.6 | 2001 Boxster S Racing Car | 1966 912 based 911 RSR replica racing car (for sale!) come and follow the Porsche Sports Cup racing fun and me at www.facebook.com/coolcavaracing
|
||
|
04-07-2006, 06:55 AM
|
|
|
Registered
Join Date: Feb 2006
Location: Hong Kong -
Posts: 527
|
29-36 wow what a change
Quote:
22-26 36 32 So I went 29-36 and wow what a marked difference. Much lighter and although a bit floaty I got used to it and really like this set up. 17 inch Bridgestone SO2"s 205/50/17 and 255/40/17. Thanks Kurt mate
__________________
Euro 1989 Carrera 3.2 Paint Code L 693 Stone Grey 45,000 kms logged Last edited by Rad Hatter; 04-07-2006 at 08:58 AM.. |
||
|
04-07-2006, 08:53 AM
|
|
|
Registered
|
Quote:
Jo Last edited by exponence; 04-07-2006 at 09:33 AM.. |
||
|
04-07-2006, 09:31 AM
|
|
1987 Porsche 911 CE CAB TL 930/20
