Soarer cont'd from page 20 (12+8)
#152
Scooby Regular
Join Date: Sep 2000
Location: Notts, UK
Posts: 4,935
Likes: 0
Received 0 Likes
on
0 Posts
What efficiency are they talking about?
You are now questioning Levelten?
Basic Physics!
The percentage of torque tansmitted through the coupling.
100% means no loss.
95% means 5% lossed to heat and mechanical losses. Engine has to use more fuel/power for the same performance and maximum performance is reduced.
Lee
#153
Lee
point taken and accepted , but i am not a rally driver and never will be .
Mycroft , i have to agree here as i am a fan of the autobox WHEN modded in a performance fashion , you dont have to be on the ball all the time etc and it seems to work really well with the turbos , whats the weight of a diablo ????
point taken and accepted , but i am not a rally driver and never will be .
Mycroft , i have to agree here as i am a fan of the autobox WHEN modded in a performance fashion , you dont have to be on the ball all the time etc and it seems to work really well with the turbos , whats the weight of a diablo ????
#154
Oh My God, 8 pages to explain Automatic gearboxes when in fact you can explain them fairly quickly,
It works like this, if you are old, infirm, mentally incapable of driving a manual or a big fat Luxo Barge driver, you have an Auto,
On the other hand if you like driving cars you have an manual, I think the Soarer no matter how fast it is, is just a Fast Car, A Fiat 500 would be more fun to drive (I have had one, was great when it worked), if you get your driving kicks just by beating other cars you are missing the point, I have driven many Automatic cars, some good, some bad but none were great.
Sell it, get a MK1 Golf GTI, Capri 2.8i or a Mini and drive at half Soarer speed and I would expect you would enjoy it as much if not more, I had a Volvo T5 which was quite fast but it wasnt much fun as a Drivers machine, even with manual gears it just didnt do 'fun'.
It works like this, if you are old, infirm, mentally incapable of driving a manual or a big fat Luxo Barge driver, you have an Auto,
On the other hand if you like driving cars you have an manual, I think the Soarer no matter how fast it is, is just a Fast Car, A Fiat 500 would be more fun to drive (I have had one, was great when it worked), if you get your driving kicks just by beating other cars you are missing the point, I have driven many Automatic cars, some good, some bad but none were great.
Sell it, get a MK1 Golf GTI, Capri 2.8i or a Mini and drive at half Soarer speed and I would expect you would enjoy it as much if not more, I had a Volvo T5 which was quite fast but it wasnt much fun as a Drivers machine, even with manual gears it just didnt do 'fun'.
#155
Cool, back from the pub and off to the club at Midnight so we thought that I ought to test your knowledge.
Q1... a car travels down the road doing 40mph round a bend at a constant 40mph and out the other side at 40mph... is that car Decelerating or Accelerating?
Q1... a car travels down the road doing 40mph round a bend at a constant 40mph and out the other side at 40mph... is that car Decelerating or Accelerating?
#156
###
Cool, back from the pub and off to the club at Midnight so we thought that I ought to test your knowledge.
###
Hahaha, Mycroft with a life - funny concept
###
Q1... a car travels down the road doing 40mph round a bend at a constant 40mph and out the other side at 40mph... is that car Decelerating or Accelerating?
###
WTF has that got to do with this thread? Now who's off-topic! LOL
Cool, back from the pub and off to the club at Midnight so we thought that I ought to test your knowledge.
###
Hahaha, Mycroft with a life - funny concept
###
Q1... a car travels down the road doing 40mph round a bend at a constant 40mph and out the other side at 40mph... is that car Decelerating or Accelerating?
###
WTF has that got to do with this thread? Now who's off-topic! LOL
#159
Wacko.. correct answer but wrong reason... whenever an object travels in a curved path, there must be an unbalanced force acting upon it so to maintain the velocity it must accelerate...
Wacko 7/10
Wacko 7/10
#161
Scooby Regular
Join Date: Feb 2001
Location: Wiltshire
Posts: 2,583
Likes: 0
Received 0 Likes
on
0 Posts
bugger... Mycroft asked a question I knew the answer to and then answers it before I get a chance!
I thought I learn't nothing in A Level physics - the examiners certainly (Grade E!)
I thought I learn't nothing in A Level physics - the examiners certainly (Grade E!)
#166
Scooby Regular
Join Date: Sep 2000
Location: Notts, UK
Posts: 4,935
Likes: 0
Received 0 Likes
on
0 Posts
Mods - please don't close this thread - move it to Muppets where it belongs.....
Lee
#169
Turned the corner...
6 or 7 speeds (the ones I know about have 7) doesn't really matter the principals are the same, keep the revs as near to ideal as possible... just as an Auto does when asked...
Can you post a link to a site with a torque curve for any Diablo motor?
All those I have found show a very steep line...
6 or 7 speeds (the ones I know about have 7) doesn't really matter the principals are the same, keep the revs as near to ideal as possible... just as an Auto does when asked...
Can you post a link to a site with a torque curve for any Diablo motor?
All those I have found show a very steep line...
#171
Guys, just curious but I saw the electronic display of an early j reg soarer and I think it looks very similar to the display which is used in the earlier toyota yaris's but in the soarer the plastic/glass infront of the display seems to magnify the display.
anyone else noticed this ???
anyone else noticed this ???
#172
Scooby Regular
Join Date: Sep 2000
Location: Notts, UK
Posts: 4,935
Likes: 0
Received 0 Likes
on
0 Posts
Not found a graph yet but found this on a Lambo club site, I have had to type it as it was in pdf format...
Torque delivery is optimized across the entire engine operating band thanks to the Variable intake system and variale valve timing.
It goes on....
Particularly noteworthy is the fact that at just 2000rpm the V12 produces more torque than the maximum value attained by the majority of grandturismo cars in todays market.
Lee
Torque delivery is optimized across the entire engine operating band thanks to the Variable intake system and variale valve timing.
It goes on....
Particularly noteworthy is the fact that at just 2000rpm the V12 produces more torque than the maximum value attained by the majority of grandturismo cars in todays market.
Lee
#173
Scooby Regular
Join Date: Sep 2000
Location: Notts, UK
Posts: 4,935
Likes: 0
Received 0 Likes
on
0 Posts
The 206 WRC only uses 5 ratio's yet its dominating the WR championship.
Why is that?
Wide spread of torque means that once its on its torque curve it will accelerate the same at 3000rpm as 5000rpm in the same gear. It doesn't need a torque convertor to lift the revs in relation to the gearbox. There is no more torque to be had by revving the engine needlessly. There is no multiplication effect available only Torque Convertor losses.
There would only be a "multiplication" if the car was pulling off the line when the TC would spin the engine up to boost levels before moveing off.
The driver however has the clutch and can do it himself.
This is why they don't use auto boxes. There is no performance advantage only losses.
We wont even start on reliability issues of putting an auto in a race/rallycar
Lee
[Edited by logiclee - 5/4/2003 9:49:03 AM]
Why is that?
Wide spread of torque means that once its on its torque curve it will accelerate the same at 3000rpm as 5000rpm in the same gear. It doesn't need a torque convertor to lift the revs in relation to the gearbox. There is no more torque to be had by revving the engine needlessly. There is no multiplication effect available only Torque Convertor losses.
There would only be a "multiplication" if the car was pulling off the line when the TC would spin the engine up to boost levels before moveing off.
The driver however has the clutch and can do it himself.
This is why they don't use auto boxes. There is no performance advantage only losses.
We wont even start on reliability issues of putting an auto in a race/rallycar
Lee
[Edited by logiclee - 5/4/2003 9:49:03 AM]
#175
Scooby Regular
Join Date: Sep 2000
Location: Notts, UK
Posts: 4,935
Likes: 0
Received 0 Likes
on
0 Posts
Claudius,
Its all about Torque and where it is developed in the rev range combined with what top speed you are expecting to get.
Take a WRC engine to easy maths spec.
It produces 500lbft of torque at only 3000rpm and will rev to 7000rpm before the power drops away. It needs to reach 140mph max on the stage so we need to gear its top gear at 20mph/1000rpm.
We need to decide what ratio first gear is going to be to be able to get it off the line with the engine on boost and if there are any very tight first gear bends.
We now need to look at how many ratio's we need to keep the car in its boost zone between first and top. If we get maximum acceleration between 3000 and 7000rpm WRC Turbo probably 5 or 6.
A highly strung BTTC racer with only a N/A 2.0 but loads or Revs may have a band of 6500 to 9000rpm, the top gear gearing will be lower but it will need more ratio's to stay in the zone.
Back to the WRC car, we have chosen our ratio's carefully and our driver will be able to stay on full acceleration whenever he needs it up to his 140mph maximum.
Should we give him an auto?
Well we are saying that with 3000rpm dialled in we have maximum shove. The torque convertor may rev the engine up to 5000rpm so what, we don't need it to do that, if we did we would have changed down a gear. We are already at maximum shove and are heading for the redline. The torque converter would just reduce the maximum acceleration possible as a percentage of your engines output is lost in the coupling.
Dont forget both the manual and auto have distinct ratio's the conventional auto does allow slip but it is far from a constantly variable transmission.
Pepper,
Yes.
Auto boxes still have to change gear but the way they change gear is different to a manual, rather than just moving a cog they have brake bands which softens the change and the Torque Converter further cushions the change as its fluid coupling and not direct.
Good autoboxes change without you even knowing unless its a full redline change. You will have heard however that the boxes "Slurr" their changes. This means the box is good at disguising the change, there will still be a small delay in power transfer.
We are talking about 300 milliseconds on the best sports auto boxes. A full race sequential manual can change within a 100milliseconds. XTrac quote around 75 milliseconds for their customer boxes, the WRC ones will be faster.
The on road SMG electronic boxes Alfa, Aston, BMW etc are a little different. Although they are a sequential manual change the box is still a "H" pattern manual box which is ECU shifted sequentially. They do not have squential internals. Because of this the fast change is limited to around 150miiliseconds (M3BMW) to around 300milliseconds(Alfa)
Lee
Its all about Torque and where it is developed in the rev range combined with what top speed you are expecting to get.
Take a WRC engine to easy maths spec.
It produces 500lbft of torque at only 3000rpm and will rev to 7000rpm before the power drops away. It needs to reach 140mph max on the stage so we need to gear its top gear at 20mph/1000rpm.
We need to decide what ratio first gear is going to be to be able to get it off the line with the engine on boost and if there are any very tight first gear bends.
We now need to look at how many ratio's we need to keep the car in its boost zone between first and top. If we get maximum acceleration between 3000 and 7000rpm WRC Turbo probably 5 or 6.
A highly strung BTTC racer with only a N/A 2.0 but loads or Revs may have a band of 6500 to 9000rpm, the top gear gearing will be lower but it will need more ratio's to stay in the zone.
Back to the WRC car, we have chosen our ratio's carefully and our driver will be able to stay on full acceleration whenever he needs it up to his 140mph maximum.
Should we give him an auto?
Well we are saying that with 3000rpm dialled in we have maximum shove. The torque convertor may rev the engine up to 5000rpm so what, we don't need it to do that, if we did we would have changed down a gear. We are already at maximum shove and are heading for the redline. The torque converter would just reduce the maximum acceleration possible as a percentage of your engines output is lost in the coupling.
Dont forget both the manual and auto have distinct ratio's the conventional auto does allow slip but it is far from a constantly variable transmission.
Pepper,
Is that right then - do seq. boxes actually shift quicker than autos?
Auto boxes still have to change gear but the way they change gear is different to a manual, rather than just moving a cog they have brake bands which softens the change and the Torque Converter further cushions the change as its fluid coupling and not direct.
Good autoboxes change without you even knowing unless its a full redline change. You will have heard however that the boxes "Slurr" their changes. This means the box is good at disguising the change, there will still be a small delay in power transfer.
We are talking about 300 milliseconds on the best sports auto boxes. A full race sequential manual can change within a 100milliseconds. XTrac quote around 75 milliseconds for their customer boxes, the WRC ones will be faster.
The on road SMG electronic boxes Alfa, Aston, BMW etc are a little different. Although they are a sequential manual change the box is still a "H" pattern manual box which is ECU shifted sequentially. They do not have squential internals. Because of this the fast change is limited to around 150miiliseconds (M3BMW) to around 300milliseconds(Alfa)
Lee
#177
Autos actually shift quicker than any manual gearbox ever will, there is zero time between changes except the change UP from '3' to 'O/D', this is due solely to its design, going down from 'O/D' to '3' there is again a zero shift time.
#178
Scooby Regular
Join Date: Sep 2000
Location: Notts, UK
Posts: 4,935
Likes: 0
Received 0 Likes
on
0 Posts
Pepper.
Forgot to add.
The on road SMG boxes have a clutch so do not suffer torque converter losses.
Look at the Alfa 156. The 2.0l selespeed SMG has near identicle performance to the 2.5V6 Q system tiptronic Auto.
The manual 2.5V6 is however considerably quicker.
Lee
Forgot to add.
The on road SMG boxes have a clutch so do not suffer torque converter losses.
Look at the Alfa 156. The 2.0l selespeed SMG has near identicle performance to the 2.5V6 Q system tiptronic Auto.
The manual 2.5V6 is however considerably quicker.
Lee
#180
Scooby Regular
Join Date: Sep 2000
Location: Notts, UK
Posts: 4,935
Likes: 0
Received 0 Likes
on
0 Posts
Mycoft,
If you take changing gear as the gap in power transmission rather than just selecting a mechanical gear you will find an auto is slower than a sequential box. Most auto boxes in sport mode have a gap of about 300 milliseconds an SMG dog box changes gear at full throttle cog to cog in 75milliseconds.
I have some Jaguar info on this I'll see if I can find it.
There is also plenty of info on the net if you need to look further.
How stuff works site that Pepper has been reading for a start.
Lee
If you take changing gear as the gap in power transmission rather than just selecting a mechanical gear you will find an auto is slower than a sequential box. Most auto boxes in sport mode have a gap of about 300 milliseconds an SMG dog box changes gear at full throttle cog to cog in 75milliseconds.
I have some Jaguar info on this I'll see if I can find it.
There is also plenty of info on the net if you need to look further.
How stuff works site that Pepper has been reading for a start.
Lee