A picture a day... Porsche
Discussion
Digga said:
Aesthetically, I'd agree, but IIRC the wheel sizings were as much to do with function - allowing larger brakes - as they are of fashion and, in that regard, are perhaps not a bad compromise.
Little known fact. Gen 1 (350mm) PCCBs will fit within 17" wheels.I'd suggest Singer went with 18s for tyre choice.
olly22n said:
Slippydiff said:
olly22n said:
I know. I interpreted the previous poster impling that the new 'r' wasn't really an 'r', when it is, iyswim?
That depends, does the 991 R have a plethora of paper thin lightweight panels and a bonnet made our of fibreglass strengthened with strips of balsa wood to ensure it's competitive ? Nope.Does it weigh close to 800kgs ? Nope.
Have a delightful gutteral sounding MF injected and durable (see below) engine ? Nope.
Is it devoid of ANY driver aids ? Nope.
Will the 991 ever win the Tour De Corse or indeed any competition event ? (show and shine events don't count I'm afraid) Nope.
Will 991 R production numbers be limited to just 19 cars ? Nope.
And then there's this small matter :
"In the fall of 1967, a 911 R attracted a lot of attention for its unusual record setting drive. Four Swiss race car drivers, Jo Siffert, Dieter Spoerry, Rico Steinemann and Charles Vögele, set out to break several endurance world records in Monza. When their Porsche 606 Carrera 6 proved to be unsuitable for the very steep drives, the Porsche factory quickly sent a 911 R as a substitute vehicle. Not only was the car driven from Zuffenhausen to Monza on its own wheels. The engine already had 100 hours on the dynomometer by then as well. The only preparation necessary was to change the gear ratios. To preserve the gear wheel of the highest gear for 96 hours at full throttle, the 4th and 5th gears were equipped with an identical high-speed gear ratio. The record drive took place in early November 1967, and it lasted three days and three nights. After 20,000 km at full throttle, five new world records and 14 international class records had been set – all at an average speed of more than 200 km/h."
Porsche AG can't make their latest, greatest GT3 engine last what ? 10,000 miles under normal driving conditions let alone at full throttle for 20,000kms/96hrs.
Whilst the latest 991 pimpmobile may be an R in name, in essence that's all it is. In reality it's just another instance of Porsche using its hard won competition and engineering heritage to sell a range of contemporary products to an ever increasing queue of badge jockeys
even when those products have absolutely NOTHING in common with their illustrious forebears, IYSWIM ? 
Porsche sale executive to potential R purchaser : "Of course being the lightweight focused model, the car has a mechanical limited slip device, this maximises traction and improves stability under braking".
Potential purchaser : "Yeees, quite, can I have the contrast stitching, a heated steering wheel and electric cup holders ? best order it with comfort seats and PDK too please"
anonymous said:
[redacted]
My point entirely dear fellow, you can get 380mm discs inside an 18" wheel. Hence my suggestion that the 18" wheels gave them the choice of modern tyres they required, and the look they sought. Wheels big enough to accommodate large brakes wouldn't have been high on their agenda.The ST weighs what 1000kgs max ? and had what 250-270hp ? from its short stroke 2.5 L engine. The Singer no doubt weighs more despite it's stunning lightweight bodywork, and packs a bigger punch, ergo it needed more rubber and brakes capable of providing retardation commensurate with said rubber.
Slippydiff said:
anonymous said:
[redacted]
My point entirely dear fellow, you can get 380mm discs inside an 18" wheel. Hence my suggestion that the 18" wheels gave them the choice of modern tyres they required, and the look they sought. Wheels big enough to accommodate large brakes wouldn't have been high on their agenda.The ST weighs what 1000kgs max ? and had what 250-270hp ? from its short stroke 2.5 L engine. The Singer no doubt weighs more despite it's stunning lightweight bodywork, and packs a bigger punch, ergo it needed more rubber and brakes capable of providing retardation commensurate with said rubber.
I stupidly bought 18" fuch for my 964 thinking that the brakes were too big to accommodate smaller wheels - which with a nice high profile period tyre look so much better. High profile tyres also give lots more feel at the relatively low speeds attained on the road. They are also much more forgiving. I have never been a lover of low profile tyres on road cars. In my opinion an Unnecessary hindrance.
Steve Rance said:
I stupidly bought 18" fuch for my 964 thinking that the brakes were too big to accommodate smaller wheels - which with a nice high profile period tyre look so much better. High profile tyres also give lots more feel at the relatively low speeds attained on the road. They are also much more forgiving. I have never been a lover of low profile tyres on road cars. In my opinion an Unnecessary hindrance.
Steve glad you brought this up. I need a little help before I invest heavily in custom wheels. Basically my 996 has the following as stock fitted:-Fronts 225/40 18 on a 7.5x18 ET50
-Rears 265/35 18 on a 10x18 ET65
Now I have also added 15mm spacers all round, to make them sit right.
So that's the starting point clarified, basically I have some Ohlins R&T which I am about to fit and I predict a drop of around 20mm from current (OEM M030 sport sus).
Now that I have removed the PAS system, I want to strike the right balance with the car; I am trying to create the best 'driver's car' and not necessarily the best 'track weapon'.
My initial thoughts are basically to stick with stock tyre sizes but eliminate the spacers with custom made wheels with custom ET's like this:
7.5x18 ET35
9x18 ET37 (can get away with dropping 1" wheel width as the 265 tyre still fits; added benefit of 0.5kg loss)
But the last few days I am really at a loss with it all. Basically there is an OEM option of 17" tyres:
205/50 17 and 255/40 17 using 7J and 9J 17's
So if I dropped down to a 205 front section this would reduce the physical effort required to manually steer the car (No PAS). My concern's are:
-Potential loss of grip
-Look pants on 17's
-Understeer
Benefits are lighter steering and lower weight. Now bearing in mind the target weight for the car is 1120kg and the idea of it being the ultimate road car rather than track-car, just wondering what your advice would be and also what GEO settings you would recommend for when I have fitted the Ohlins R&T with custom adjustable pillowball top mounts.
I have a motorsport company in the process of providing me a quote for custom forged wheels in my chosen Fuchs style or Oz ALLEGGERITA style.
Just to clarify, if running 17's I would have the ET as such that they stick out in the arches to the same degree the 18's would i.e 7x17 ET 29 front and then 9x17 ET37 rears.
Not to open up another whole can of worms but to lighten the steering again I have considered reducing the front track by 5mm each side (from the ET mentioned above) and I could also drop the castor angle. So many variables to consider and I don't want to make any expensive mistakes as I am having to produce 5 sets at a time as a minimum order, and custom forged wheels don't come cheap (i.e when I spoke to Fuchs, they have an 18month production run currently and for custom wheels I would need to be shifting 100 wheels a month min with likely €60K tooling costs to offset).
ETA my apologies guys, nearly forgot to add some pics:
My work on all things pork today:
Edited by CarreraLightweightRacing on Sunday 16th October 06:58
Gassing Station | Porsche General | Top of Page | What's New | My Stuff