18" Technology's on C2T
01-11-2002, 09:36 AM
#16
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Adrian - your warning is acknowledged and I confess I have not yet put this car on the track. As with any track event, it has always been my policy to take a few laps, then bring the car in to inspect it to ensure nothing unexpected is happening. So when this one goes out, I will pay particular attention to my tires and the inside wheel arches.
Farzaan - anxiously awaiting the photos. I like your goals.
Farzaan - anxiously awaiting the photos. I like your goals.
01-11-2002, 10:53 AM
#17
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Dear JBH,
Track work will certainly sort things out. My sole goal in life is to bring to peoples attention the possible problems. Not every one has them but when they do I do not want them coming back to me (us) saying why did we not tell them. Recently a guy installed exactly the same set up on his C4 as I have on mine (wheels and tyres that is) and guess what. They rubbed on one side. We still have not worked this out.
All I ever say is be sure before you part with your money. Be EXTRA careful when purchasing off ebay. Just helped a guy out there as well. Nearly bought a set of BBS wheels said to every Porsche made. In the nick of time managed to stop that one.
Ciao, and good shopping guys. Be careful out there,
Adrian
911C4
Track work will certainly sort things out. My sole goal in life is to bring to peoples attention the possible problems. Not every one has them but when they do I do not want them coming back to me (us) saying why did we not tell them. Recently a guy installed exactly the same set up on his C4 as I have on mine (wheels and tyres that is) and guess what. They rubbed on one side. We still have not worked this out.
All I ever say is be sure before you part with your money. Be EXTRA careful when purchasing off ebay. Just helped a guy out there as well. Nearly bought a set of BBS wheels said to every Porsche made. In the nick of time managed to stop that one.
Ciao, and good shopping guys. Be careful out there,
Adrian
911C4
01-11-2002, 10:56 AM
#18
Guest
Posts: n/a
Porsche has issued two technical service bulletins which raise questions about the retrofit of 18" wheels to certain Porsches.
The first technical service bulletin is entitled "Installation of 18" Wheels Not Approved" (15 April 1993, Group 4, Number 9305). The bulletin indicates that "retrofitting 18" wheels on Porsche vehicles which do not have 18" wheels as original equipment is NOT ALLOWED." In the original, the capitalized words "NOT ALLOWED" also appear in bold type. The bulletin also notes that "endurance tests have shown that equipping certain Porsche vehicles with 18" wheels in an application not already approved by Porsche Cars, N.A. may result in loosened bolts and/or threaded connections on the front wheel carriers. This, in turn, may cause fractures in these components. Fractures may also occur in the front strut mounts and in the body in the area of the rear suspension as a result of the installation of 18" wheels not already approved for installation for this specific application." The bulletin adds that "such damage can occur without warning and the vehicle may become very hard to control or steer as a result of this improper installation." Finally, the bulletin notifies Porsche dealers of two requirements: "Porsche dealer personel coming in contact with a vehicle that has been retrofitted with 18" wheels not approved by Porsche should inform the owner of the vehicle of the potential for damage to their [sic] vehicle and loss of steering control. Porsche Cars, N.A. should also be notified of any vehicles retrofitted with 18" wheels."
The second technical service bulletin--"Summer Tire/Wheel Rim Summary" (5 August 1993, Group 4, Number 9309)--provides specific information about the wheels used on the 1994 911 Turbo: the wheels and tires installed on that car "are not approved nor recommended to be installed on any Porsche other than the 1994 911 Turbo." The wheels and tires in question are identified.
Front wheel: 8Jx18
52 mm offset
part number 965 362 136 01
225/40 ZR18 tire size
Rear wheel: 10Jx18
61 mm offset
part number 965 362 140 01
265/35 ZR18 tire size
(The part numbers which I have identified are for polished--not painted--wheels.)
Similar bulletins dealing with the retrofit of 18" wheels to certain cars in the 993 series were issued but eventually superseded. However, the 15 April 1993 and the 5 August 1993 technical service bulletins have not been superseded.
The first technical service bulletin is entitled "Installation of 18" Wheels Not Approved" (15 April 1993, Group 4, Number 9305). The bulletin indicates that "retrofitting 18" wheels on Porsche vehicles which do not have 18" wheels as original equipment is NOT ALLOWED." In the original, the capitalized words "NOT ALLOWED" also appear in bold type. The bulletin also notes that "endurance tests have shown that equipping certain Porsche vehicles with 18" wheels in an application not already approved by Porsche Cars, N.A. may result in loosened bolts and/or threaded connections on the front wheel carriers. This, in turn, may cause fractures in these components. Fractures may also occur in the front strut mounts and in the body in the area of the rear suspension as a result of the installation of 18" wheels not already approved for installation for this specific application." The bulletin adds that "such damage can occur without warning and the vehicle may become very hard to control or steer as a result of this improper installation." Finally, the bulletin notifies Porsche dealers of two requirements: "Porsche dealer personel coming in contact with a vehicle that has been retrofitted with 18" wheels not approved by Porsche should inform the owner of the vehicle of the potential for damage to their [sic] vehicle and loss of steering control. Porsche Cars, N.A. should also be notified of any vehicles retrofitted with 18" wheels."
The second technical service bulletin--"Summer Tire/Wheel Rim Summary" (5 August 1993, Group 4, Number 9309)--provides specific information about the wheels used on the 1994 911 Turbo: the wheels and tires installed on that car "are not approved nor recommended to be installed on any Porsche other than the 1994 911 Turbo." The wheels and tires in question are identified.
Front wheel: 8Jx18
52 mm offset
part number 965 362 136 01
225/40 ZR18 tire size
Rear wheel: 10Jx18
61 mm offset
part number 965 362 140 01
265/35 ZR18 tire size
(The part numbers which I have identified are for polished--not painted--wheels.)
Similar bulletins dealing with the retrofit of 18" wheels to certain cars in the 993 series were issued but eventually superseded. However, the 15 April 1993 and the 5 August 1993 technical service bulletins have not been superseded.
01-11-2002, 02:31 PM
#19
Drifting
Thread Starter
Adrian, maybe we can all work together to make your information for your book even better. Let's look at what could be causing these problems rather than to outright say it won't work.
My personal opinion is that it is likely something to do with the alignment specs. Perhaps your C4 friend is using more negative camber than you, thus it rubs on the inside or maybe not enough camber and it's rubbing on the outside edge.
Even though Porsche was not the most consistent manufacturer in the late 80's, early 90's, I would have to think that the bodies would at least be very, very close to each other in tolerances. Perhaps we need to explore the reasons why things are rubbing, not fitting, etc.
Maybe we should post up our alignment settings and suspension settings to give you some more data to work with. I might be totally off here, but it's worth a shot considering how detailed your book sounds like it will be.
My car so far:
Suspension: RUF (front ROW springs w/progressive rear RUF springs, Bilstein coilovers front and rear)
Height: 24.75" front through centre of wheel to fender lip. 24.5" rear through centre of wheel to fender lip.
Alignment:
Front:
Camber: -1d30m
Caster: 3d15m
Toe: 0d
Rear:
Camber: -1d30m
Toe: 7m total toe-in
Tires: Bridgestone S-02 N1 225/40R18 & 265/35R18
Wheels: 18" Technology for narrow body 993, 18x8 +52mm and 18x10 +65mm
I will be autocrossing the car this sunday over a bumpy track so I can report back any rubbing problems. So far, on the street through some really rough roads, there has been no rubbing.
Farzaan
My personal opinion is that it is likely something to do with the alignment specs. Perhaps your C4 friend is using more negative camber than you, thus it rubs on the inside or maybe not enough camber and it's rubbing on the outside edge.
Even though Porsche was not the most consistent manufacturer in the late 80's, early 90's, I would have to think that the bodies would at least be very, very close to each other in tolerances. Perhaps we need to explore the reasons why things are rubbing, not fitting, etc.
Maybe we should post up our alignment settings and suspension settings to give you some more data to work with. I might be totally off here, but it's worth a shot considering how detailed your book sounds like it will be.
My car so far:
Suspension: RUF (front ROW springs w/progressive rear RUF springs, Bilstein coilovers front and rear)
Height: 24.75" front through centre of wheel to fender lip. 24.5" rear through centre of wheel to fender lip.
Alignment:
Front:
Camber: -1d30m
Caster: 3d15m
Toe: 0d
Rear:
Camber: -1d30m
Toe: 7m total toe-in
Tires: Bridgestone S-02 N1 225/40R18 & 265/35R18
Wheels: 18" Technology for narrow body 993, 18x8 +52mm and 18x10 +65mm
I will be autocrossing the car this sunday over a bumpy track so I can report back any rubbing problems. So far, on the street through some really rough roads, there has been no rubbing.
Farzaan
