The RS America Spare Wheel.

Part# 965 362 130 00

Size.

Despite one of the major selling points of the RS America being the 17” diameter wheels from the 965 (the correct factory designation for the 964 Turbo), the spare wheel that came stock was only 16” diameter and was only 5 1/2” wide.

Fitted to this miniscule rim was a hefty 165/70-16 collapsible tire. It is really no wonder that it is limited to “short time use” with a maximum speed of 50 mph.

It bears a “965” part number because it is the same spare that came with the 1993/1994 Turbo.

Usage limitations.

It is obvious that the spare wheel is really intended just to get you to the nearest garage or tire shop - or at the very most to get you home (assuming your puncture occurs near home).

A 5 1/2” rim with a 165mm tire composed of very soft compound rubber in order to expand after being collapsed for an indeterminate length of time - is not going to last very long transmitting 125 horsepower to the road.

This is why the label on the tire itself states in bold print “For short time use only. Max. 50 mph/80 kph. Replace by standard wheel as soon as possible.” The owners handbook has the same precautionary notes.

Where to put it the spare and supplement WKD 964 221 92.

Interestingly enough, there is an anomaly in the owners manual regarding the instructions for use of the spare wheel.

Specifically the issue is whether the spare should be placed on the front or the rear of the car. It is not as simple as replacing whichever wheel has the flat tire on it, it becomes an issue of car control after fitting the spare - which of course is a safety issue, and leads to the owners manual instructions requiring legal counsel due to Porsche's potential liability when instructing owners where to fit the spare.

If you look at page 92 of your owners manual, you will see a paragraph stating that the spare must be fitted to the front of the car only. In fact there is a section stating words to the effect that if you have a flat in the rear, you should fit the spare to the front of the car on the side of the car that has the flat, and then replace the rear wheel (which has the flat) with the front rim you just removed to fit the spare.

The logic here is that you do not put the wider 255 tire on the front and limit steering travel .......... However!

If fitment of the spare significantly reduces the tires contact patch with the road, and adds a significantly softer compound to whichever end of the vehicle that you fit it to, it therefore compromises the performance.

If I had a choice where I would like to lose tire performance, and the options were:

I think I'm pretty sure I know where I would put the spare!

I believe Porsche considered this and that this is the reason behind the revision to page 92 of the owners manual. This revision consists of a one page supplement (Part# WKD 964 221 92) inserted into the clear sleeve at the very back of the owners manual - which incidentally, is also where the RS America owners manual supplement was intended to be located.

The owners manual revision basically removes the instruction to fit the spare to the front of the car under all circumstances, and softens the message to say that the car has “improved handling and less wear on the tires” with the spare fitted to the front.

NOTE: a few copies of supplement WKD 964 221 92 are now available to registry members [Show me]

The later? version of the 964 spare wheel.

The debate arises because both types bear the same part number, but as you can clearly see from above, they are two distinctly differing configurations - i.e. the “spoke” configuration and the hole configuration. If you have data on which was first - please e-mail me.