GT3 vs CSL - few questions
Discussion
ABS itself is an interesting topic. My CSL doesn't have it any more as part of the departure to Motec management. I did contemplate fitting one of the motorsport ABS systems, but provided the car is setup well in terms of weight transfer (and driven properly) along with properly setup brake bias, it should be possible to brake to the limit without Abs and still avoid lockup. One thing we have done is lose the servo, and this would allow enough feel to avoid sudden lockups. The obvious benefit of ABS is that you can just bury the pedal and let the car sort it out, in theory. In reality, I found problems on certain circuits or with poor surfaces. Bumpy circuits like Oulton, and braking on the "marbles" caused huge problems. There were many times I wanted to remove the ABS, but couldn't without the standard ECU sending me into limp home! I think on balance, a race car is better without ABS if you have balance and good traction (i.e. slicks)
DoctorD said:
Paul, I agree with the logic of your argument but I've been in the passenger seat with Steve R and watched him do as he describes. It certainly works with the RS although it's a more aggresive style than I used to use when racing a 964 RS (in the dim and distant past). To be fair, I can brake to the limit of the tyres grip in my CSL and still not activate the ABS (on track) and yet on the road on loose surfaces I know it still works. Perhaps the RS is similar. ABS systems are so finely tuned these days that on the best cars they are really unobtrusive.
Yes I agree with Paul. Both cars are driven slightly differently to get the most out of them. The 964 is reletively low on power and torque compared to the GT3 and can be run stiffer at the rear so you can drive it more on the throttle than the RS. It is like a big go kart. Great car
Steve R
madou said:
... I think on balance, a race car is better without ABS if you have balance and good traction (i.e. slicks)
Why was it used in Formula 1 when the regulations allowed ? Were they using systems which did not suffer the limitations of road car ABS ?
I comes down to the software basically, the ABS on my GT3 is a nightmare, I hate it and have to adjust my style to drive around it. That is because it is very agressive and is set up for relatively inexperienced drivers so it cuts in at the merest hint of slip. Once it cuts in you loose 50% of your front braking. On the cup cars and RSR's there is a motorsport abs unit which is much less agressive and consiquently cuts in a lot later giving the driver far more scope to modulate his braking.
Evoblade clearly has the same problem with his CSL. Formula one cars are completely different, the have much less weight, much more grip, little weight transfer so once the grip runs out there is little the driver can do about it. The ABS software in these cars was triggered by slightly different criteria, However F1 cars do have fully adjustable brake bias so the driver can switch his brakes towards the rear of the car on low grip or wet surfaces which is more beneficial than triggering the ABS.
Steve R
I would guess most good drivers beat(threshold break) the abs in the dry anyhow. In the wet maybe another story and hence the switch in the cup car! The 964RS abs is in any case maximised for retardation NOT steerability unlike the standard 911's.I would guess this is the same for later RS versions and GT3's
And Steve you mean to say you actually looked at the speedo going into eau Rouge!!!
>> Edited by lemon yella rs on Thursday 10th March 20:10
And Steve you mean to say you actually looked at the speedo going into eau Rouge!!!
>> Edited by lemon yella rs on Thursday 10th March 20:10
Fantastic thread guys - really good info!
For my part I reckon ABS is undesirable on track but worthwhile on road...it's not for the occasions when you're focused and in the groove (with no pedestrians/drivers that lack any sort of spatial awareness around), it's for the times when you're late en-route home from work, or encounter a diesel spill/muddy road right in a braking zone...
Saying that, I had no ABS on my 911 G50 Carrera and I never missed it despite giving the car serious stick on quite a few occasions...I recall using engine braking (with heel/toe) on entry to balance the car back then...so I reckon Steve's spot on.
Still interested to have any thoughts on the Manthey conversion. I'm thinking that (despite some posts advocating the standard setup) that a Mk1 with Manthey suspension will out-perform a Mk2 pretty much everywhere. Thoughts?
Leaning (heavily) towards a Mk1 car in the wake of all this info...and yes, I agree that the GT3 is 'more special' than the CSL.
One thing that most people seem to ignore is that (despite the likely fact that the CSL IS almost certainly easier to drive close to the limit than a GT3) the GT3 has way more grunt. In the real world (fast road driving), having substantially better acceleration has got to be a major advantage...especially with Manthey K400, suspension, and brakes fitted
For my part I reckon ABS is undesirable on track but worthwhile on road...it's not for the occasions when you're focused and in the groove (with no pedestrians/drivers that lack any sort of spatial awareness around), it's for the times when you're late en-route home from work, or encounter a diesel spill/muddy road right in a braking zone...
Saying that, I had no ABS on my 911 G50 Carrera and I never missed it despite giving the car serious stick on quite a few occasions...I recall using engine braking (with heel/toe) on entry to balance the car back then...so I reckon Steve's spot on.
Still interested to have any thoughts on the Manthey conversion. I'm thinking that (despite some posts advocating the standard setup) that a Mk1 with Manthey suspension will out-perform a Mk2 pretty much everywhere. Thoughts?
Leaning (heavily) towards a Mk1 car in the wake of all this info...and yes, I agree that the GT3 is 'more special' than the CSL.
One thing that most people seem to ignore is that (despite the likely fact that the CSL IS almost certainly easier to drive close to the limit than a GT3) the GT3 has way more grunt. In the real world (fast road driving), having substantially better acceleration has got to be a major advantage...especially with Manthey K400, suspension, and brakes fitted
But that's the point, the GT3 Mk1 'doesn't' have way more grunt, not unless you spend money on tuning it up. In standard form the CSL has 'identical' power and even 'identical' peak torque to the GT3. Using manufacturer published figures the CSL even weighs slightly less. So it's not surprising that on a track such as Bedford with GT3 and CSL accelerating along the same stretch of 1km straight neither will pull out a gap. It then comes down to braking, traction and balance and the competence of the driver to extract the maximum from each. The GT3 Mk2 has more power but then it weighs more also and from a drivers eye view the standard GT3 Mk2 certainly doesn't pull as strongly as a GT3 RS.
Tuning wise the GT3 Mk1 seems to be capable of 410-420 bhp in the capable hands of guys such as Manthey, but the CSL is about done for road use at 380 bhp although 400-420 bhp is achieveable if intended for track use only. Apart from Ferrari's 3.6 litre engine, nothing comes close to the grunt these engines deliver from such modest capacities.
>> Edited by DoctorD on Thursday 10th March 23:33
Tuning wise the GT3 Mk1 seems to be capable of 410-420 bhp in the capable hands of guys such as Manthey, but the CSL is about done for road use at 380 bhp although 400-420 bhp is achieveable if intended for track use only. Apart from Ferrari's 3.6 litre engine, nothing comes close to the grunt these engines deliver from such modest capacities.
>> Edited by DoctorD on Thursday 10th March 23:33
The Manthey suspension is sublime I doubt if there is a better upgrade out there for the MK1, the K400 is a bit mad it corrupts the power delivery basically loads more and I mean loads more mid range grunt/ torque: the power comes on like a turbo it pulls very hard and quickly to 7800rpm & then just falls away. Its very hard to describe as standard the car has a very liner delivery: with the K400 it just blasts quickly to its max bhp. Out of the two upgrades the suspension wins for me and the extra power is the icing on the cake. Oh and don't forget to change the 4 pot to 6 pot calipers,larger discs & SRF brake fluid that makes a massive difference on track.
Russell
Russell
phatgixer said:
I'm at Spa on April 5/6 with the CSL if anyone wants a passenger lap to see just how good it really is...
*cough* Is this offer open to Pug drivers too?
Might just pop by for this. Have been in a CSL as a passenger around the Ring countless times, but around Spa would be very nice!
ABS a bad thing on a race car ? Hmmmm I wonder how many of you would be able to outbrake a GT3 cup car were you relying on "the force". The great thing about the ABS is the confidence it gives, especially in less than perfect conditions. You don`t have to allow that little room for error every time you come into a braking zone. You can pick your mark and hit it with pinpoint accuracy every time. It also helps when conditions change and your car is not set up accordingly. The ABS helps to overcome any set up errors in braking. And as for bumpy tracks like Combe or Croft - no contest!
The reason the GT3 R/S doesn`t have ABS is because the FIA banned it in one of their "making racing affordable" moments.
Henry
The reason the GT3 R/S doesn`t have ABS is because the FIA banned it in one of their "making racing affordable" moments.
Henry
Henry, I was really referring to road car ABS systems on cars converted to race or for trackday use. But it does really depend on how well the braking and suspension set up is.
The whole point about being a good race car driver is being able to detect grip and traction from the seat of your pants and hence modulating when threshold braking, and when trail braking. No need for the force
It is true that ABS will correct issues such as problematic brake balance on variable circuits, avoiding lockup and possibly a shagged tyre or two, particularly where a single braking setup won't work across all corners, but it is just masking the problem and I dislike the resultant elongation in braking distance.
At least without ABS you can decide what happens under problematic conditions on a track. A good driver will have plenty of spare brain capacity to deal with this, and infact will deal with it automatically without thinking.
ABS is a useful safety feature though, when the unexpected happens. I always strive to reduce the weight of a race car, so it is a balancing act. One one side, the safety or reduced complexity a driver aid provides. On the other, more weight.
There is nothing a driver aid can do that a driver can't. I can hear the argument that "we are only human" - but I would argue that a really good racing driver has his abilities thoroughly programmed, and driving is simply repetition of unconcious abilities. That brings them alot closer to a machine in ability.
Obviously not mny people are that good though!
The whole point about being a good race car driver is being able to detect grip and traction from the seat of your pants and hence modulating when threshold braking, and when trail braking. No need for the force
It is true that ABS will correct issues such as problematic brake balance on variable circuits, avoiding lockup and possibly a shagged tyre or two, particularly where a single braking setup won't work across all corners, but it is just masking the problem and I dislike the resultant elongation in braking distance.
At least without ABS you can decide what happens under problematic conditions on a track. A good driver will have plenty of spare brain capacity to deal with this, and infact will deal with it automatically without thinking.
ABS is a useful safety feature though, when the unexpected happens. I always strive to reduce the weight of a race car, so it is a balancing act. One one side, the safety or reduced complexity a driver aid provides. On the other, more weight.
There is nothing a driver aid can do that a driver can't. I can hear the argument that "we are only human" - but I would argue that a really good racing driver has his abilities thoroughly programmed, and driving is simply repetition of unconcious abilities. That brings them alot closer to a machine in ability.
Obviously not mny people are that good though!
evoblade said:
Henry, I was really referring to road car ABS systems on cars converted to race or for trackday use. But it does really depend on how well the braking and suspension set up is.
The whole point about being a good race car driver is being able to detect grip and traction from the seat of your pants and hence modulating when threshold braking, and when trail braking. No need for the force
It is true that ABS will correct issues such as problematic brake balance on variable circuits, avoiding lockup and possibly a shagged tyre or two, particularly where a single braking setup won't work across all corners, but it is just masking the problem and I dislike the resultant elongation in braking distance.
At least without ABS you can decide what happens under problematic conditions on a track. A good driver will have plenty of spare brain capacity to deal with this, and infact will deal with it automatically without thinking.
ABS is a useful safety feature though, when the unexpected happens. I always strive to reduce the weight of a race car, so it is a balancing act. One one side, the safety or reduced complexity a driver aid provides. On the other, more weight.
There is nothing a driver aid can do that a driver can't. I can hear the argument that "we are only human" - but I would argue that a really good racing driver has his abilities thoroughly programmed, and driving is simply repetition of unconcious abilities. That brings them alot closer to a machine in ability.
Obviously not mny people are that good though!
I agree entirely.
My braking points simply do not allow ABS to deploy. The resultant loss of grip would put me off on every corner. ABS, is an extemely ineficient for of braking. I love racing againt drivers that rely on it.
But imagine racing against a driver who has good brake pedal feel and lifts pressure just before the wheels lock but still has abs there just to help sort out any individual wheel issues ! Having cut my teeth on SC`s, 3.2`s and the dreaded 930`s you either learn fast or crash, but I still wouldn`t give up the cup car`s ABS !
If you fancy your chances the first round of the Britcar is March 25th / 26th at Silverstone. I`m sure they could squeeze you in somewhere and there looks to be some very strong competition so it`ll be a steep learning curve !
Keep smiling
Henry
If you fancy your chances the first round of the Britcar is March 25th / 26th at Silverstone. I`m sure they could squeeze you in somewhere and there looks to be some very strong competition so it`ll be a steep learning curve !
Keep smiling
Henry
Henry-F said:
But imagine racing against a driver who has good brake pedal feel and lifts pressure just before the wheels lock but still has abs there just to help sort out any individual wheel issues ! Having cut my teeth on SC`s, 3.2`s and the dreaded 930`s you either learn fast or crash, but I still wouldn`t give up the cup car`s ABS !
If you fancy your chances the first round of the Britcar is March 25th / 26th at Silverstone. I`m sure they could squeeze you in somewhere and there looks to be some very strong competition so it`ll be a steep learning curve !
Keep smiling
Henry
Good point Henry
I hadn't considered any other ABS involvment other than on the fronts since they get most of the bias. It would be interesting to establish whether the ABS is being triggered more often than I thought. I will ask Porsche if they can get that data from the ECU. Does anyone know if they can? They won't turn off the ABS unit for me and a motorsport unit - like the one fitted to a cup car is 2.5K plus vat.
Would love to join you in Britcar this year Henry but its GT's next year for me - on saying that it could well be Britcar because I think it is a better series.
Henry, I would be inerested to hear your thoughts on driving GT3's comming out of SC's. I know a few drivers who hate GT3's because they say the bump steer is too disconserting. The RS doesn't have a lot but earlier cars suffered from it at the rear.
Steve R
Have any of you guys seen the DVD called 'Bending the Rules' available at the www.carlimits.com website. It's not the best driving video but it does very clearly demonstrate the effects of different braking techniques including no-ABS, threshold braking and then full-ABS.
What's interesting is that it shows the best technique to be threshold braking mixed with ABS, which has the shortest braking distance. I cannot remember how simple non-ABS threshold braking compared with ABS asssited threshold braking, but the key message that they demonstrate (supporting steve rances comment) is that a purely ABS stop (i.e. just slamming on the brakes and relying on the electronics) is vastly inferior to what a skilled driver can do with the same equipment.
Worth a look if you can borrow a copy.
What's interesting is that it shows the best technique to be threshold braking mixed with ABS, which has the shortest braking distance. I cannot remember how simple non-ABS threshold braking compared with ABS asssited threshold braking, but the key message that they demonstrate (supporting steve rances comment) is that a purely ABS stop (i.e. just slamming on the brakes and relying on the electronics) is vastly inferior to what a skilled driver can do with the same equipment.
Worth a look if you can borrow a copy.
DoctorD said:
Have any of you guys seen the DVD called 'Bending the Rules'............ is that a purely ABS stop (i.e. just slamming on the brakes and relying on the electronics) is vastly inferior to what a skilled driver can do with the same equipment.
I wouldn't say the ABS full on stop was vastly inferior as there was only a cars length difference between that and the threshold braking.
An example; we ran 2 964s at N.Weald in the wet, one with ABS and one without. Even with practice I couldn't better 2 car lengths longer on the ABS equipped car with my non ABS car. The ABS car was consistant in it's braking distances whereas my car was more variable which means on track I would need margin for error but the ABS car could pick a known braking point shorter.
FWIW Andrew easily beat my best distance but not the ABS car ( although we were on different tyres which would influence the braking distance0
The difference in braking distances between perfecr threshold braking and incompetant all locked up clutch in braking in a non ABS car is enormous though.
Which brings the point of the driver skill factor in racing into focus. If an ABS equipped car with a novice can brake within 1 cars length of an F1 driver in the same car does it not remove the driver involvement?
Well-done Henry, some good comments.I hear you let the morris loose in your car!
What is all this about abs being inferior? When we are talking track lap times,or safer driving,or racing against other like cars and drivers, be it racing, sprinting or just friendly rivalry ,who gives a what ever, if its got abs or not, If they are all alike, you get the best you can out of what ever style of driver and car.
But you can be shore, in a cup car, if your are not deploying the abs at some points of the circuit, you are not driving fast enough or hard enough for those 100ths of a second or more ,of course that’s if you want the times ,but if you are just having a fun track day out ,who gives a monkeys any way ,just have fun.
If some of the cars abs ,is not working that well, and you want to get your times down, get the motor sport abs units, which can be tuned to the car.
Some sample best times on the day,at spa.
968 cs with standard abs on mich pilot cups 2.53(this car did actually qualify a 2.51) I thought this was impressive.
911 3.2 carrera on mpcups 2.53 non abs
993 cup car 320bhp on mpcups 2.50 race abs, probably a 2.48 in the car.
996 cup on mich slicks 2.34 race abs.
Modified 993 rs on Dunlop do1j 2.46 (370bhp)and 1130kg.Standard abs.
Your best qualifying times can very often come from getting on the ragged edge of grip! If you try and stay super smooth and totally balanced all of the time, and not use your abs, i would doubt that you would be on pole position for your class, or even 2nd or 3rd!
If you want driver involvement ,drive a cup car /race car or any other car, and try and get pole for your class or match the times! I think you would then agree that you will have enough driver involvement!
Its a interesting thread with different views and perspectives, on what’s quickest!!
What is all this about abs being inferior? When we are talking track lap times,or safer driving,or racing against other like cars and drivers, be it racing, sprinting or just friendly rivalry ,who gives a what ever, if its got abs or not, If they are all alike, you get the best you can out of what ever style of driver and car.
But you can be shore, in a cup car, if your are not deploying the abs at some points of the circuit, you are not driving fast enough or hard enough for those 100ths of a second or more ,of course that’s if you want the times ,but if you are just having a fun track day out ,who gives a monkeys any way ,just have fun.
If some of the cars abs ,is not working that well, and you want to get your times down, get the motor sport abs units, which can be tuned to the car.
Some sample best times on the day,at spa.
968 cs with standard abs on mich pilot cups 2.53(this car did actually qualify a 2.51) I thought this was impressive.
911 3.2 carrera on mpcups 2.53 non abs
993 cup car 320bhp on mpcups 2.50 race abs, probably a 2.48 in the car.
996 cup on mich slicks 2.34 race abs.
Modified 993 rs on Dunlop do1j 2.46 (370bhp)and 1130kg.Standard abs.
Your best qualifying times can very often come from getting on the ragged edge of grip! If you try and stay super smooth and totally balanced all of the time, and not use your abs, i would doubt that you would be on pole position for your class, or even 2nd or 3rd!
If you want driver involvement ,drive a cup car /race car or any other car, and try and get pole for your class or match the times! I think you would then agree that you will have enough driver involvement!
Its a interesting thread with different views and perspectives, on what’s quickest!!
burzel said:
Modified 993 rs on Dunlop do1j 2.46 (370bhp)and 1130kg.Standard abs.
Hi Paul,
I don't want to totally hijack this (very interesting) thread, but I take it this car is your red sprint/hillclimb car?
It is very light. Isn't it a "Comfort" spec 993 RS originally? (I notice the rear wing is the smallr "Comfort" type. How did you lose so much weight from the car? Standard weight is 1270 kg is it not?
I'll have to weigh my car one of these days.
Hi johnny
The car is light,ali doors and bonnet,minimal roll cage,fikse wheels,ali under floor panels,light weight exaust & headers,no heater,no air con,light weight seats,no vario ram,carbon rear lid and standard rs rear spoiler,which is lighter than the club sport version,plastic door windows,no window openers or mech in doors.The car did start out at 1290kg,i could possibly get the car below 1100,but do not want to spoil the look of the car.It looks pretty standard when its just parked up. But it has been built as a focused hillclimb and sprint car.
The car is light,ali doors and bonnet,minimal roll cage,fikse wheels,ali under floor panels,light weight exaust & headers,no heater,no air con,light weight seats,no vario ram,carbon rear lid and standard rs rear spoiler,which is lighter than the club sport version,plastic door windows,no window openers or mech in doors.The car did start out at 1290kg,i could possibly get the car below 1100,but do not want to spoil the look of the car.It looks pretty standard when its just parked up. But it has been built as a focused hillclimb and sprint car.
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