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OK. I finally took the plunge and picked up a couple of real 7Rs.
What tyres can I fit to them, considering that they need to fit a '68 SWB with a 7mm spacer (as per original homolgation papers) and no flare on the rear arches?
Edmund Harris, who knows a thing or two about this, suggested fitting the same tyre on the rear as on the front - that being 185/70/15. However, Longstone were concerned because the recommended fitting for the tyre is 5.5" to 6". They were happier in that I said I'd fit tubes.
Any help gratefully appreciated, as I want to get them on the car asap...
"Racing is life. Everything before or after is just waiting."
Thanks. So, do you think that 215/60 (say Avon 6RZZ) will fit underneath a SWB without hacking the arches? What would they have had in period, assuming they did not change the arches?
"Racing is life. Everything before or after is just waiting."
Clearance varies to some degree from car to car & from one brand of tyre to another since not all tyres of a given size are actually the same width !
A 7mm spacer is very small - where did that figure come from ?
To quote the Factory's 1968 'Sports Purposes ' Manual :
"For the 911 T, 911 S and 911 L (in Group 5) the 7" rim has been homologated and approved for use on the rear wheels. With this equipment the vehicles have a rear track of 1365 mm (53.74").
For the 7" rim, 27 mm (1.063") spacers and longer wheel bolts must be used.
As for tyres, since they were used in competition, they were usually fitted with 5.50 M-15 tyres.
Andy
“Adding power makes you faster on the straights; - subtracting weight makes you faster everywhere”
Yup. Sorry. Stand corrected. I read the 7mm spacer as being for the 7R, but it is for the 6" deep six (page 35/36 of the same book you referred to).
Good job I bought a pair of 7mm and a pair of 27mm spacers from Type-911 recently
When they say 'vehicles starting with the '68 model have a hub 7mm wider at the front than the previous 911 models and a 7mm spacer at the rear....' does that mean '68 SWB, or '68 LWB - or is the LWB always referred to as '69 models onwards?
"Racing is life. Everything before or after is just waiting."
Lightweight_911 wrote:I'm fairly sure that the hubs were changed for the '68 swb models - the same part number was then used up to the '73 models (& later).
Charlotte's 68 swb has 7mm spacers at the rear and before I read this I thought they were aftermarket, but I guess not? It has 15x5.5 wheels btw.
2006 RHD 997 Carrera (but DDK remains in my heart - also now no longer)
1972 LHD 2.4T with '73 2.4T CIS motor - gone to a new DDK home
1994 RHD 993 Carrera - gone!
1968 LHD 911L - was the Wife's but now in new hands
As it happens, I found out that my SWB has 7mm spacers on the rear as well. On Sunday I finally put the 7Rs on the back. I'll post photos tomorrow...
So, does a 7R with a 215/60/15 Avon CR6ZZ tyre fit on the back of a stock '68 SWB? Well, not with a 7mm spacer it doesn't. Fit a 27mm spacer on top of the 7mm spacer, and yes it does. It also clears the swing arm nuts or whatever they are as well. There is now plenty of space and clearance.
Problem is, it (sort of) looks wrong but I can't put my finger on it. I think it's the tyres, not the wheel or the spacers.
The other problem is that the main alternative was to fit 185/70/60 Avons, which I am fitting to the front on some Deep sixes. When I was down at Vintage Tyre Services, it looked a bit of a stretch on a 7R, and Vintage Tyres were unhappy about fitting the 185 Avons to the 7Rs. But, this route does have two advantages:
1. No need to have a 34mm spacer on the back, and wondering when, not if, the half shaft is going to break.
2. You can fit tubes, which Vintage Tyres said could not be done to a 60 profile tyres as you can't get them.
The only other alternative was the Avon 205/70/15 tyres which looks fantastic and very period, but is really tall and would make it look like a funny car, so that's probably a non-starter. However, I could probably fit the 205s to both the front and back, and then lower the car. Hmm, that's an idea.
So, has anyone tried to fit 7Rs on the back with 215/60/15s on an SWB - with no rear flare? I've looked at the Pelican board with the comments there about fitting the tyres, but sorry, I have now tried what they have suggested and I think they are writing fiction to say 'they fit underneath with no trouble' to quote someone on the board.
"Racing is life. Everything before or after is just waiting."
Photos of the 7Rs fitted - please note that the suspension hadn't settled, even with my weight leaning on the back of the car and the paint isn;t as good as it looks here :
"Racing is life. Everything before or after is just waiting."
Julian - it's difficult to tell since, as you say, the suspension hasn't 'settled'.
Is your car running with the standard ride height ?
I would say that the wheels/tyres would look (& perform) fine but the car would benefit from a slight lowering all round with a touch of increased negative camber at the rear.
Andy
“Adding power makes you faster on the straights; - subtracting weight makes you faster everywhere”
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