In Love

[davidsl500]

Today one of my clients turned up in his new love - an 05 Bentley Continental GT. I sat in it but alas thats all. What an absolutely superb piece of equipment. I offered him my SL and a tenner - he said no (actually not quite what he said but I am keeping it clean).

I want one, I need one !! Give me it now !

 

[television]

Today one of my clients turned up in his new love - an 05 Bentley Continental GT. I sat in it but alas thats all. What an absolutely superb piece of equipment. I offered him my SL and a tenner - he said no (actually not quite what he said but I am keeping it clean).

I want one, I need one !! Give me it now !

When I was deputy technical secretary for the RREC I used to get to drive all of these things. When the Mulsane first came out around 82, that was the start of these 2 ton machines that could get to 60 in 5-6 sec. It was always said that 20% of all of these cars were off the road at any one time through being vandalized.

Malcolm

 

[SLinKyjoe]

a guy at my gym has one and let a retired gentleman drive it round the car park. he was absloutley full of it. he was telling me about it. I mentioned i had the SLK, and if he wanted a passenger ride in that he could. he was delighted to be.

before i drive it hard, i explained that it was very powerful and that i had no intention of trying to frigthen him. he said it takes alot for him to be scared. so i asked if he was ready and holding on. he was. we went.

he went quiet. i accelerated up to 100 and back twice. then stopped. he said he was wrong, he was scared and that this car was the fastest thing he had ever been in by a long way. i then said i will put it in sport mode then!!!*

when he got his breath back, he said if he wins the lottery, he is buying it off me. so i guess he liked it!

he asks me everytime, if i have brought the black beauty to the gym.

personaly the new bentley doesnt quite hit the spot for me. i do like it but not enough to want one. the Aston DB9 volante, on the other hand......

anyhow, my car has been accepted for the London to Silverstone supercar tour, and a few SLR's and maybe a Buggatti Veyron should be there. i shall take some piccies for those who want to see.

suprisingly, Bentley isnt on the list, but a BMW M6 is? strange.

* Tuesday next, it gets an ECU remap to 400BHP and the speed delimiting. am just doing some calculations to estimate its top speed. the one i have done at the mo, says its theoretical max speed is 214. think the caluclator is duff. mind you, taking wind etc in to consideration, 400 may power it beyond 180.

thats abit boy racer isnt it?

 

[SLinKyjoe]

When I was deputy technical secretary for the RREC I used to get to drive all of these things. When the Mulsane first came out around 82, that was the start of these 2 ton machines that could get to 60 in 5-6 sec. It was always said that 20% of all of these cars were off the road at any one time through being vandalized.

Malcolm

that first bentley turbo was my dream car, alongside the bentley speed 6 of 1929. WO knew how to build real cars.

they still knock up the arnage red label, or is it black? (£175,000) in crewe, which is just an evolution of the turbo from the 80's. when BMW owned them, they stuffed in the 5.4V12 and sales plummetted, so they did the red label and shoved in the 6.75ltr v8 again. It was that which made BMW flog it to VW. and the fact they wanted Rolls-Royce! there was a point around 1989 when 51% of all RR and Bentley sales were attributed to the Turbo! so the Mulsanne, the eight and the shadow picked up the rest. they sold about 1500 cars that year.

and remember the flying spur. the turbo stuffed into the roller. Micheal Jackson bought one. they only made 50 and it was so popular they re-did as the flying spur 2 a few years later. if you wanted to buy one, Rolls sent you to a hotel in the Lakes for the weekend and one was delivered to you for approval during your stay! Class!!

what i like about the new Bentley continental, is its a VW pheaton underneath. At least a Mercedes is a mercedes underneath!

 

[Blobcat]

* Tuesday next, it gets an ECU remap to 400BHP and the speed delimiting. am just doing some calculations to estimate its top speed. the one i have done at the mo, says its theoretical max speed is 214. think the caluclator is duff. mind you, taking wind etc in to consideration, 400 may power it beyond 180.

thats abit boy racer isnt it?

The limiters can be there in name only on quite a few cars, have you tested that it does not go past 155?
On the M5 BMW the limiter is only on 6th, if you go past 155 in 5th then change up the limiter does not halt play. Audi S4 on TV went up to an indicated 175 before the limiter. However I find at intergalactic speeds the speedo is so far out as to be useless. I generally have 2 GPS based devices sat on the dash and trust them.

 

[SLinKyjoe]

there is more than one electornic limiter on the car. in 5th, 6th and 7th the car will stop accelerating at 156mph. this limited is set in the gerabox brain.

if you remove that, it stops accelerating again at 173. however AMG software can remove that limiter as well which is found in the ECU. you are ment to have a different rear lower spolier and front end something or other before you do that, as the standard AMG aero package is only type rated to 174. so AMG say.

with 360bhp i doubt it would get higher than that anyway, but with 400 it should pass 180 ish. according to a ratio calculator, it theoretically can do 188 with the bhp and wheels and gears this car has.

but as it is rated at 32MPH in 7th, for every 1000rpm and red lines at 6700, then that suggests 214. or in 6th at 28.5mph it may do 190. With 400 that may be possible.

 

[Blobcat]

Is the 7g gearbox up to the additional power? I notice that the E, CLS & S all have the 5 speed auto in the AMG55. Do you need any modifications to the brakes / susspension?

 

[davidsl500]

The Bentley has 552bhp, 0-60 4.7 and tops out at 198mph - mind you it weighs almost 2.4 tonnes... I did see the video of the Flying Spur which is the 4 seater version doing 212mph -verified by gps.

 

[SLinKyjoe]

Is the 7g gearbox up to the additional power? I notice that the E, CLS & S all have the 5 speed auto in the AMG55. Do you need any modifications to the brakes / susspension?

yep. the 7GT accpets upto 700nm. the car will only be producing 560nm after the remap.

and the latest CLK63 has 486BHP with a 7Gtronic.

so no worries on that front.

not sure if the tyres will cope tho.

the brakes are more than capable. AMG up the power and dont recommend that the brakes need upgrading, unless you want them upgrading of course.

 

[davidsl500]

not sure if the tyres will cope tho.

I run "Y" rated tyres which are good for 186mph. Cant find anything better than this on a quick search - but there must be something.

I have seen an indicated 158mph in the SL - not in this country obviously, and at that speed things happen very quickly. It is frightening to think that if you pass a vehicle doing, say 70mph, you pass him at 88mph as though he was standing still. If you look down at the speedo and then look up at the road again you will have missed 230 feet of road! Oh, and by the way, the car is impeccable at that speed.

So after the remap will one be attempting a flat out run?

 

[SLinKyjoe]

yep.

the car apparently indicates 160 ish at 155mph. just checking for tyre figures at the mo. i shall be doing one lap of silverstone, but it may have speed restrictions so am not sure what it will allow.

the other way to find out is to go to one of the V-Max events and get the chance to have a go down the 2 mile runway.

did think about the nordschlief but cant get the time off this year for it.

could also go to a track day, but need to hold back on the idea of using the car as a track car. didnt get it for that reason. still, we shall see.

had a look at the tyres, they are ZR-Y rated. which means 186+MPH. they have some figures on that bit too.

 

[davidsl500]

Always been confused by the "ZR" Rating - I thought it meant 149+mph. Tyre manufacturers seem to be a bit vague on it. Some (like Goodyear) say the ZR rating may appear in the code and when you look at the coding its says something like 255ZR18-Y and lists it as 186mph max.

If it is 149mph+ then can I do 600mph on it please ? (see what I mean?)

Is there a Tyre Specialist in the house please !! (if there is, what are you doing in my house?)

I think your lap at Silverstone will be a procession/parade and you will probably be briefed on the speed of that prior to the event !

Even a 2 mile runway is tight to do speed runs - you need a good braking zone - I am trying to remember what the Aston's terminal speed was when they tried to do a maximum speed run on a runway (5th gear TV Program I think it was). I dont think they got anywhere near it.

Track days wont get you close either - If you had a 30 second start on an F1 car it would still nail you on one lap and it wouldnt hit 200mph on the straight. So needs to be a nice straight German Road I reckon - or a banked oval.

 

[SLinKyjoe]

The tyre ratings have additons. ZR's come in different ratings as they have different top speed allowances. the 186+ tyres normally have an ultimate of 208. to go beyond that you have to have tyres made for higher speeds which are often made to suit a particular vehicle. this is one reason why the real fast cars like SLR's Enzo's and Carrara GT's have speeds just over 200 and in the case of the SLR, and restricor at 207. this then allows buyers to purchase tyres from any tyre manufacturer that produces the correct tyre type and size.

The Ford GT however does 212, and the buggati veyron does 252. both however are limited number cars like the McLaren F1. all use Bridgestone tyres. Altho Michelin do produce a suitable tyre. but you have to order it.

Now, the SLK has 7 gears. the MPH for 7th/per 1000 rpm is 32mph and in 6th/per 1000 rpm is 28.5mph. so the following can be used as reference for theortical top speed.

The max power peak is 5750rpm, the car will no doubt peak 500rpm or so either side of that. It changes up at 6400rpm and redlines at 6700rpm

so in 7th you have 3 related top speeds.
184, 204.8 & 214.4
In 6th you have
163.8,182.4 & 190.95

as the cars max power will peak around 5750rpm then the 184 (7th) or 182.4 (6th) areas should prove about right. its this area where the car is at its best for top speed.

So all we need now is the power actually needed to power the car against the wind and overcome the friction on the tyres. http://www.pumaracing.co.uk/topspeed.htm

now that suggests a power of 307 at the fly wheel to get to 170MPH. The SLK produces 360BHP, if you estimate tranny losses of about 17% this works out at about 299BHP. In standard tune the SLK will make 173-174. so thats about right. with 400bhp and the same calculation we end up at the wheels with 332. again that would possibly allow the car to get to around 180 or so. One BHP-Ratio calculator suggested 188. so looking at the gears and peak powers I have, and the evidence i have got so far, i would expect around 185ish to be the cars true potential.

Right, the interesting bit now is the parade lap. We assume (We being me and 2 others) that there will be a pace car at the front, one in the middle and one at the back. we know we have a convey of 50 supercars to do this lap with. they hope a Buggatti Veyron is one of them, and several SLR's are already lined up. Enzo's Ultima's Astons and TVR's are also possibly going to be there. so this leads to an interesing problem for the organisers. which car will become the pace car! you see, if we as a group decide to power past the front pace car, its gonna have to be some car to catch up, pass us and slow us down again! and as its only one lap, the penalty of being asked to leave the circuit doesnt really apply, as we will have done the lap we wanted. so thats gonna be a problem.

that would suggest they have taken that into question. i would expect we would have some speed control requirement, and i would expect them to give the hangar straight as the bit were we could, shall we say, boot it. you could safely provide a braking point to slow people. so we could give it a bit as it were. now if they did that, we would follow the instructions to the letter, as going outside that could be dangerous. but if they fully control the speed, they may risk it.

now if that were the case, i would expect that the 800metres of hangar straight should allow for around 165mph. and maybes 180 for the buggati. bear in mind that you could safley enter the straight at around 100mph.

At bruntinghtorpe, they estimate around 210mph as the potential top speed. 204 has been acheived on it. and the santa pod raceway could produce similar. so thats what i will look at just to satisfy the curiosity. Elvington do RWYB days 2.

I am aware that autobahns can have derestricted zones, but to be honest, public roads are not the place for that kind of speed.

Which leads to the last question everyone will be thinking, Why bother having it remapped in the first place?

Because i can, is the answer. and my defence here is, i dont wish to die with some fun still left in the bank.

 

[SLinKyjoe]

and something i just remembered. the speed rating is the tyre rating that the car can safely stand all day. IE it is built to run at 208 for a long periods without blowing up or shredding. the allowance will be within tolerances, so you could probably get well beyond that for a short period. as long as you dont go daft. the SLR at full speed will run out of fuel in 19minutes.

and then you would actually have to be able to do that!

bear in mind that some Corsa's come with H rated tyres. this provides a 130mph rating. what corsa could do that?

 

[SLinKyjoe]

some other stuff

http://www.tyres-online.co.uk/techinfo/speed.asp
http://www.blackcircles.com/general/speedrating
http://www.performancealloys.com/tyre_tech.asp
http://www.pirelli.co.uk/en_GB/tyre...8_gb.jhtml;jsessionid=ON3ARB3M21JXHFYKJOPCFEY
http://www.yokohama.co.nz/understand.htm#speed

its not very clear tho is it?

 

[television]

and something i just remembered. the speed rating is the tyre rating that the car can safely stand all day. IE it is built to run at 208 for a long periods without blowing up or shredding. the allowance will be within tolerances, so you could probably get well beyond that for a short period. as long as you dont go daft. the SLR at full speed will run out of fuel in 19minutes.

and then you would actually have to be able to do that!

bear in mind that some Corsa's come with H rated tyres. this provides a 130mph rating. what corsa could do that?

On the bit about run all day at 208 mph, does that really come into it, FI tyres are finished after a few hours.If you were to drop the speed to say to 175 you could get the tyres changed while you were in Mc Donalds having lunch

Malcolm

 

[davidsl500]

and something i just remembered. the speed rating is the tyre rating that the car can safely stand all day. ?

Not So SlinkyJoe ! The ECE30 regulations cover the speed ratings/markings and the tests are suprisingly little ( well relatively speaking). i.e

For a Y rated tyre : fit tyre to the manufacturers reccomended rim size, inflate to manufacturers recommended level (or ECE Table if not specified), acclimatise in the testing room for 3 hours (20-30 degrees C), recheck tyre pressure. Set up on testing rig - 2m diameter smooth steel drum, apply load to tyre equivalent to manufacturers maximum recommended load, run tyre up to max speed less 30kph for 20 mins, then max speed less 20kph for 10 mins, 10kph for 10 mins and finally max speed for 10mins (all consecutive tests). The tyre is deemed to have passed the speed rating if there is no cord/ply damage, tread seperation/chunking - and after 6 hours rest the diameter has not varied by more than +/- 3.5%. So in reality it is only tested for 10 mins at max speed and on the manufacturers reccomended rim size and pressure - deviate from that and you could be in the Twilight Zone!!

 

[SLinKyjoe]

good find. but looking at that, it was run pretty close to maximum limits for 30mins. and as the cars have been fitted with tyres that exceed your speed limit by some margin, then you are reasonably secure with your tyre choice, should you have your car upgraded a bit.

we have speed limits on our vehicle tyres here, It says not to exceed 45mph. so we asked Michelin, who supply the tyres, if we have to exceed 105kph every month to meet regulations. why is the tyre only 45mph rated. they said, if you drive up and down the motorway, the tyre is rated to drive at a maximum of 45mph all day. exceed that and it may start to fail. however the tyre itself will take the full load at speeds of up to 70mph. they did some checking when we said we get up to 83mph!!!!

they got back to us and said how long for. about 300yards we said. they laughed and said not to worry. they wont burst. they said we could exceed its design limits by some margin for small amounts of time. its the permenant rotation that causes them problems.

For Malcolms benefit. they last 800miles and cost between£800 and £1500 each.

mind, we only do 8miles a day. which at 0.8mpg is about enough really.

 

[SLinKyjoe]

get out of the way!!!!

 

[Myros]

Joe, the nordschliefe

has claimed the cars and lives of more people than it ought to have done. I wouldn't recommend it for a full bore trial of you lovely SLK unless you were prepared to have it trailered home or sent back in boxes, possibly with you joining it in a similar state.
You would be able to get up to some hairy speeds and gs, but probably nowhere near the theoretical top whack of your newly upgraded motor.
You would get the chance to meet Sabine Ringmeister though. Is there an ulterior motive to your prospective trip to Nurnburg?