Having recently spoken to an expert, concensus is Cup Cams, with the power delivery from 5,500 RPM surging any Cup Drivers (or anyone else) here share this?
Cup Cams?
- Thread starter carreraboy
- Start date
Deary me .... little low down torque .... But the power comes on with a surge once I hit about 5,500 Revs per minute and is progresive to 6,700 Rev per minute, my old lightweight had a much different power delivery band as other RS Carpets, was told probably have 3.8 or Cup Car Camshafts, they are those long irregular things that go round and round on top of the engine[
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Any other or Cup Car drivers have a similar power delivery?
]Any other or Cup Car drivers have a similar power delivery?
interesting. So the Carrera cup cars had different cam ? can you elaborate as I always thought the cams for both RS and cup were the same ? Only difference being the intake filter and exhaust ? (oh and maybe sintered clutch plate)
As far as I was aware, the cup car engines are mechanically identical to the RS except for the items Laurence mentioned plus no rear blower (bypass pipe instead) and a different DME (also mapped for the cup car exhaust or lack thereof). One upgrade mentioned by Colin Belton is to use 993 Cup cams - maybe that is what is being referred to.
Yes Ian sorry forgot about the other stuff.
Hacki
Active member
AFAIK there´s no mechanical difference. The Cup engines are indeed specially built - so the have special numbers, too - with selected parts, but not with special cams. The difference is the DME, mapped for some extra 25 horsepower in the higher rev region as I was told by a Porsche engineer many years ago. (and of course the details the other guys mentioned above)
The power delivery is friendly on mine, it hasn´t got that two stroke race engine character that you mentioned.
Rgds
Hacki
The power delivery is friendly on mine, it hasn´t got that two stroke race engine character that you mentioned.
Rgds
Hacki
My RHD car is one long pull from 3,000 right through to 6,500 ? Standard I'm sure. And as smooth as silk.
The Motec car equally has a wide but an even more full torque curve which is fantastic for bringing the tail into play even from quite low revs. But before the Dissies were done, although the Motec sounded stronger, you couldn't squeeze a cigarette paper between the actual performance of the two. 9m reckoned -50bhp ... now found of course.
The 993RS has a noticeable lift at around 4400 rpm ? I assume the Varioram ? But still a very wide power band.
Lift above 5,000 ? Only felt this on the GT3 ... and a rally prepared Peugeot 205 GTi ! Sounds like cams --- as diagnosed, but which ?
The Motec car equally has a wide but an even more full torque curve which is fantastic for bringing the tail into play even from quite low revs. But before the Dissies were done, although the Motec sounded stronger, you couldn't squeeze a cigarette paper between the actual performance of the two. 9m reckoned -50bhp ... now found of course.
The 993RS has a noticeable lift at around 4400 rpm ? I assume the Varioram ? But still a very wide power band.
Lift above 5,000 ? Only felt this on the GT3 ... and a rally prepared Peugeot 205 GTi ! Sounds like cams --- as diagnosed, but which ?
SpeedService at Spa said 3.8 Cams .....
But what is the overall power situation ?
A lot of the Revo maps on naturally aspirated cars seem to boost the top end, but at a cost to the mid range ?
I tried a free trial on my GT3 and really didn't think the net gain was worth much --- the slightly hollow mid balancing the richer top end --- and losing around 3 mpg on the computer ?
Maybe a stop watch would have told a rather different story ...
A lot of the Revo maps on naturally aspirated cars seem to boost the top end, but at a cost to the mid range ?
I tried a free trial on my GT3 and really didn't think the net gain was worth much --- the slightly hollow mid balancing the richer top end --- and losing around 3 mpg on the computer ?
Maybe a stop watch would have told a rather different story ...
Just dug out the dyno charts on mine and it shows peak power at 6200rpm and peak torque at 5240rpm with a flattish curve from 4850-5600rpm, if that makes any sense!!
There is a definite 'switch' that one can feel about 5200-5500 where the push and the sound changes....nice!
There is a definite 'switch' that one can feel about 5200-5500 where the push and the sound changes....nice!
As an ex-endurance racer it would make sense if the last engine rebuild was geared for carrying hi=revs ... little workable power down low but Comes on at 5,500 ...
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