What's going on here then... - Page 2 - 911/Carrera GT - PistonHeads UK

I am fairly new to the world of RS Porsches and thought it best to start a thread to contain all my questions in one place rather than the on-going sporadic questions here and there. The car is basically a 7.1GT3RS but has been upgraded to affectively become a 7.2GT3RS extreme if you will. Today I had a look at a few areas: the gearshift seems incredibly short. I measured the throw between neutral position and then 3rd, which was 44mm (measured from the upper surface of the gear knob as per pic below. Question is, is this shorter than standard? The car has been upgraded to 3.8l as per the GenII and also has the CUP/GenII airbox fitted. The car is around 100kg lighter than stock due to various carbon-Kevlar components/Ti exhaust/light carpets.... I removed the airbox today to get a closer look at the engine. To me it seems that 1-2 ancillaries have been removed and thus contribute to the diet plan. From the pictures below do you know if this is the case? Is this filter in the CUP/GenII airbox standard (seems to be a paper element with a foam outer layer). Throttle assembly measures around 90⌀ is this stock? Some other engine shots just in-case you spot something else non standard To be continued...

There is no ac-compressor nor power steering pump in your engine bay. That saves quite a lot of weight. You might sweat some on hot summer days though..

JarmoL said: There is no ac-compressor nor power steering pump in your engine bay. That saves quite a lot of weight. You might sweat some on hot summer days though.. Many thanks JarmoL I'm hoping the sweating is a small price to pay for the permanent grin to be had from dropping all that weight

nice spec your auxiliary belt is routed wrong (common mistake). it should go over the alternator then feed to the right of the larger pulley below. Edited by keep it lit on Monday 12th January 11:08

keep it lit said: nice spec your auxiliary belt is routed wrong (common mistake). it should go over the alternator then feed to the right of the larger pulley below. Edited by keep it lit on Monday 12th January 11:08 Keep it lit glad you like what's left of it With the 2x ancillaries missing my guess is a completely different belt length is used and is obviously re-routed to suit new configuration. It looks about the most logical placement to me as it currently sits (good contact on all pulleys with ribbed side correctly contacting the ribbed pulleys).

VGS is Ansgar Weissen who (apart from being a very experienced builder/tuner himself) did/does the ECU programming for Manthey, that is pretty encouraging for you. I'd love to see the actual measured DIN weight (full tank) - 100kg is a lot to shed on one of these ?

TB993tt said: VGS is Ansgar Weissen who (apart from being a very experienced builder/tuner himself) did/does the ECU programming for Manthey, that is pretty encouraging for you. I'd love to see the actual measured DIN weight (full tank) - 100kg is a lot to shed on one of these ? Weight loss comes from the following mainly: -Delete A/C system. -Replace PAS system with CUP system. - Akrapovic Titanium exhaust system including Manifolds, 100cell cats, silencers, rear box, tail pipes Minus 17.5kg - Cargraphic Carbon door cards - Cargraphic Carbon doors - Carbon Kevlar bonnet - Carbon front wings +1” wider - Lightweight carpet set -17.5kg -Rear spoiler Gen II 3.8l in carbon - 19” BBS Lightweight wheels - CUP OMP steering wheel I will weigh the car myself when I get a chance. The front cage extension may also have been fitted at the time of last being weighed along with some fuel and the tyre inflation pump so it might be lighter still. But even from the list above I have no reason to doubt that minus ~100kg would be the outcome, the corner weight printout figures also confirm this. I was also told that VGS are about the best in the business, so it is good to hear from an outsider that they are a reputable company The Engine and gearbox upgrades were carried out by a specialist Porsche engine builder called Michael Kessels would also does a lot of work with VGS motorsport. VGS then did all the dyno work and ECU mapping. Here is the dyno printout: Edited by Richie200 on Monday 12th January 15:22

please excuse the phone pics and my car is in storage thus difficult to access but you'll work it out. your aux belt length is correct, it's just yours is routed wrong. my RS also has no a/c etc. your RS is very similar spec (panel) wise to mine, which on the scales with a 1/4 tank of fuel weighed 1240kgs.

Many thanks for the info Ade and for taking the trouble to go and take a picture I'll have another look at mine and sort the belt. 1240kg sounds great, was your car this weight when you bought it or was it reduced under your stewardship? If the latter, was the 100kg drop really noticeable?

My 6RS was bought modified, I've only since added a Cup gearbox and a big f k off rear view mirror Carbon; bumpers, doors, bonnet, decklid, spoiler, wheels (Dymag). All Poly windows (glass screen) No carpet, no a/c, no radio, no airbags. Full RS cage, Recaro SPG's & Schroth harnesses. Lightweight custom Cup headers & backbox. I also run a 6.1CS which although has a modified 3.9 engine, low ratio gearbox & solid suspension, hasn't been lightened in a dramatic fashion and weights a fairly standard 1395kgs (full CS cage). The 150kgs difference between the two is mind blowing on track, most noticeable is cornering speed, acceleration and braking. Losing weight is the most effective and crucial mod out there!

That looks an absolute weapon, and such a unique car. Thanks for sharing Ade What kind of geo setup?

Hi Rich, geo as follows.. Front: -4.5*neg camber & 1/2mm toe in. Rear: -3.5*neg camber & 2mm toe in. Slicks: F 250/650/18 & R 300/650/18.

Forgive my ignorance, but aren't carbon doors without any sort of side-impact protection a little sketchy?

keep it lit said: Hi Rich, geo as follows.. Front: -4.5*neg camber & 1/2mm toe in. Rear: -3.5*neg camber & 2mm toe in. Slicks: F 250/650/18 & R 300/650/18. I thought it looked very aggressive in the picture must be absolute riot

utgjon said: Forgive my ignorance, but aren't carbon doors without any sort of side-impact protection a little sketchy? It you go for a bare door you are right. If you look at the second door picture above you can see a Kevlar brace built into the door. I also have the full cage in mine.

Richie200 said: It you go for a bare door you are right. If you look at the second door picture above you can see a Kevlar brace built into the door. I also have the full cage in mine. Ahh ok - didn't spot the bracing certainly an interesting car, thanks for sharing

Guys, on the weight thing you really need to fill the tank up before weighing, without doing so it is hard to compare like for like. If you start from factory weight numbers (ie you don't actually weigh yours pre weight loss program) then they are supposed to be DIN ie with 90% fuel load, if you weigh yours with "1/4" tank that could be 50kg out for a 65l car and nearly 70kg out for the 90l option. Maybe a bit pedantic but after being stung buying a Ruf CTR quoted as 1060kg (back in the day) only to find out it weighed 1228kg DIN I strated taking an obsessive interest in the subject. Great cars, enjoying the thread

Fantastic thread. And no mention of contrast stitching as in the 991GT3 one

Dr S said: Fantastic thread. And no mention of contrast stitching as in the 991GT3 one Lol

TB993tt said: Guys, on the weight thing you really need to fill the tank up before weighing, without doing so it is hard to compare like for like. If you start from factory weight numbers (ie you don't actually weigh yours pre weight loss program) then they are supposed to be DIN ie with 90% fuel load, if you weigh yours with "1/4" tank that could be 50kg out for a 65l car and nearly 70kg out for the 90l option. Maybe a bit pedantic but after being stung buying a Ruf CTR quoted as 1060kg (back in the day) only to find out it weighed 1228kg DIN I strated taking an obsessive interest in the subject. Great cars, enjoying the thread Fuel weighs 0,7 kg per litre. So full 65 l tank weighs 45 kg or so..

SG is generally considered about 0.78 so 65lt would equal 50.7kg; atmospheric conditions will obviously alter the Specific Gravity but generally not by a great deal say between 0.74 -0.82

TB993tt said: Guys, on the weight thing you really need to fill the tank up before weighing, without doing so it is hard to compare like for like. If you start from factory weight numbers (ie you don't actually weigh yours pre weight loss program) then they are supposed to be DIN ie with 90% fuel load, if you weigh yours with "1/4" tank that could be 50kg out for a 65l car and nearly 70kg out for the 90l option. Maybe a bit pedantic but after being stung buying a Ruf CTR quoted as 1060kg (back in the day) only to find out it weighed 1228kg DIN I strated taking an obsessive interest in the subject. Great cars, enjoying the thread Thanks for your input TB993tt Lovely car the RUF! DIN is 90% fuel + driver + 7kg luggage, oh and the car: so in your car it would be (assuming 90l fuel tank) 1060+70+75+7=1212kg. In the case of 997GT3RS I think they are 1375kg stock with no fuel/driver etc. It is this that I base my 100kg weight loss on as it now weights 1274.5kg. At this point though I do not know if this includes the front cage extension/some fuel...

Dr S said: Fantastic thread. And no mention of contrast stitching as in the 991GT3 one I wouldn't dare stray into such an obviously emotive subject area (380 pages and counting) This thread is just for the boring stuff

JarmoL said: Fuel weighs 0,7 kg per litre. So full 65 l tank weighs 45 kg or so.. It's nearer to 0.75 (0.737), making 65litres c48kgs so to the nearest 5kgs it is closer to 50 than 45 /pedantmode

I am giving the car a rather thorough check over before unleashing her in the spring. Anyone know if these top mounts are stock? Just the way they sit inside the wheel arch seems a little odd to me? Could be completely normal though as the top mount mating surface as stock is a very unusual asymmetrical shape. NOTE:I am aware that the mounting holes have been elongated, I am not questioning this aspect