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Welcome to the board :byee55amg

723Nm torque is very impressive as well.
 

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Ashok Arora said:
Welcome to the board :byee55amg

723Nm torque is very impressive as well.
I drove the base 535D last week and I have to say it is quite a car. I would have to work hard to lose it in my E39 m5 on the straight. It doesn't have the cornering balance or surefootedness of the M car though, so cornering is a different matter. It's quite a nose-heavy car. I was however quite disappointed with the ride. Compared to a 520i loaner it was quite rough. I blame the run-flats, they suck!

Rob
 

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dont worry.. the meatiness of the diesel is only at lower gears... in 4th and 5th it runs out of gear and the e39 m5 will gain ;) but in a light-to-light race i imagine this engine is a tough opponent...
 

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Welcome @ the board! - That sounds great. that means the strongest pcar diesel, vw V-10 TDI isnt the strongest anymore (@313iHP)
 

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AJ said:
dont worry.. the meatiness of the diesel is only at lower gears... in 4th and 5th it runs out of gear and the e39 m5 will gain ;) but in a light-to-light race i imagine this engine is a tough opponent...
I think you might be wrong on this one. Since the car has 2 turbos one works in low rpm and the second one in high. So this diesel unlike others has the power all the time. That is whats so special about this diesel. My dad owns a E60 545i M/paket and I know that E60 535d has a better acceleration from 80 - 120km/h than the E60 545i. AND THATS IMPRESSIVE:M5launch: :M5launch: :M5launch: :M5launch:
 

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Leon82 said:
I think you might be wrong on this one. Since the car has 2 turbos one works in low rpm and the second one in high. So this diesel unlike others has the power all the time. That is whats so special about this diesel. My dad owns a E60 545i M/paket and I know that E60 535d has a better acceleration from 80 - 120km/h than the E60 545i. AND THATS IMPRESSIVE:M5launch: :M5launch: :M5launch: :M5launch:
the fact that the m5 has more power means that puts more torque to the ground than the diesel when operating in high engine rpms, the extra rpms of SI over CI allow it to be geared to provide more tractive effort (force). Look at the power! this tells the m5 has more top end torque to the ground which is most noticeable in a 4th and 5th gear race. The diesel would have good bottom end and midrange grunt though.
 

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in so many words- what digger said.

or to put it differently- the diesel has more tq, but fewer revs (lower redline). this forces the gearbox to be geared very long so the diesel will not run out of revs at higher speeds. well, it just happens so that even with its monstrous torque, at higher speeds the gearing is so steep that it actually puts less tq to the wheels thus providing weaker acceleration.

on the same token, at lower and midrange, where roadspeeds are lower and allow shorter gears, the diesel shines.

a rule of the thumb is that diesels are superior to 100ish mph (more torque, ok gearing) and petrol engines- above that (less torque but much more favorable gearing resulting in more tq to the wheels)...

alex
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It would interesting to see a tuner setup the turbos to run parallel. I wonder what that would do to the power output? I know its popular on the Supra's and RX-7's.
 

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alibo70 said:
It would interesting to see a tuner setup the turbos to run parallel. I wonder what that would do to the power output? I know its popular on the Supra's and RX-7's.
actually both cars in question have sequential turbos. parallel turbos are typical for V-engines so one turbo can feed one bank. however, on the rx7 there are two sequential smaller turbos running all the time (if i remember correctly) and on the supra the 2 sequential turbos have different housings and are controlled electronically for one to provide boost below 4500 rpms and the other to join in above that..

alex
few cars
 

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romeara said:
I drove the base 535D last week and I have to say it is quite a car. I would have to work hard to lose it in my E39 m5 on the straight. It doesn't have the cornering balance or surefootedness of the M car though, so cornering is a different matter. It's quite a nose-heavy car. I was however quite disappointed with the ride. Compared to a 520i loaner it was quite rough. I blame the run-flats, they suck!

Rob
I have a 545i with sports suspension and it too rides hard. I have changed the run-flats to regular tires and it has made the ride a little better. Not enough to justify the expense..... I wish I had skipped the sports package (no Active steering, SMG or ARS)......... I am hoping the M5 will have a better ride (probably not)......
 

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AJ said:
actually both cars in question have sequential turbos. parallel turbos are typical for V-engines so one turbo can feed one bank. however, on the rx7 there are two sequential smaller turbos running all the time (if i remember correctly) and on the supra the 2 sequential turbos have different housings and are controlled electronically for one to provide boost below 4500 rpms and the other to join in above that..

alex
few cars
My literature research project for my degree was with respect to the recent introduction of sequential turbochargers into the diesel passenger car market in particular the 535 in question.
It doesnt suffer from the small power band that most high power turbodiesels have due (as has already been stated) to the inline use of a low pressure and high pressure turbocharger. The small high pressure turbo allows for the large low pressure high mass flow rate turbo to be matched to higher RPM preformance with no loss of low end torque (as this is where the small tubo opperates). It doesnt come in one big lump like a lot of tubo diesels, its over a much wider range.
Very impressive IMO and one of the best systems out there, the old RX7 ran a similar set up, but ive read that it was plagued with problems in the turbocharger change over region (like when overtaking, if you went out of the range of the primary charger, then lifted a little and then on it again you wouldnt drop into the primary turbo range so would be left with hideous lag untill the larger secondary stage spooled up).
I dont think any supras ran a sequential set up, mearly a twin set up, so that both turbo's could be matched to the lower and mid range RPM pressure ratio requirements, but with there being two, would also stay within the compressor map in the high RPM high mass flow rate region. (ie less 'lag' and broader torque curve).

I would like to drive one of these E60 535's one of the salesmen at the BMW garage we deal with said that does go like **** off of the proverbial teflon shovel! :wroom: :D
 

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coombsie66 said:
I would like to drive one of these E60 535's one of the salesmen at the BMW garage we deal with said that does go like **** off of the proverbial teflon shovel! :wroom: :D
Coombsie, thanks for the explanation - I can tell you this car is really quite something. I drove one for about an hour and gave it a real good thrashing. Its traffic light performance is amazing. I'm sitting there behind a hard-driven sports bike at the lights, then just dump the accelerator and hold on. The bike had to work really hard to lose us. Incredible.

My 993 twin turbo also had the sequential turbo tech. Amazing thump in the back power.

At the end of the drive I checked the 535D consumption: it stood at around 23mpg. Not great in my opinion. I was driving it pretty hard, but that's the way I drive. Apart from the terrible ride that's the only downside . It's a bit of a bonfire of the vanities in my opinion. People buy diesels for long range and fuel economy. That's the reason I test drove it - I'm sick and tired of filling up my m5 every 2-3 days. I drove my wife's V70 to Brussels and back last week, using *less* than a tank. Even doing 110mph average on the E40 the car was returning 38mpg. Not filling up saves you 20-30 minutes per leg!

Rob
 

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romeara said:
My 993 twin turbo also had the sequential turbo tech. Amazing thump in the back power.
Who fitted the custom manifolds, turbos, ecu and intake set-up to your 993TT?

It's just that the 993TT and 996TT are both parallel turbos, not sequential as stock. Only the 959 had sequential turbos.

Guy
 

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Makes one wonder....


... E90 335D "speed-factor" ?? Possible ? what do you guys think ? This Speed-Factor model would have more hp than currtent M3 and pretty much twice as much Torque. That would be a GOer indeed, M3 -> D3 ;)

Or why not Cabrio 635D ?? :confused: :confused: "D6" (yeah, sound odd doesn't it)
 

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GuyGT2 said:
Who fitted the custom manifolds, turbos, ecu and intake set-up to your 993TT?

It's just that the 993TT and 996TT are both parallel turbos, not sequential as stock. Only the 959 had sequential turbos.

Guy
Really Guy? :confused2 I was labouring under the misapprehension they were sequential. When you read the reviews of the time they describe how the turbos are set up to cover different stages in the power curve. They used this to explain the lack of turbo lag. Well it was and still is a beast to drive. Thanks, I learn something new every day. :1:

Rob
 

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digger said:
the fact that the m5 has more power means that puts more torque to the ground than the diesel when operating in high engine rpms, the extra rpms of SI over CI allow it to be geared to provide more tractive effort (force). Look at the power! this tells the m5 has more top end torque to the ground which is most noticeable in a 4th and 5th gear race. The diesel would have good bottom end and midrange grunt though.
ofcourse i would never compare it to the m5cherrsagai
 

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coombsie66 said:
I dont think any supras ran a sequential set up, mearly a twin set up, so that both turbo's could be matched to the lower and mid range RPM pressure ratio requirements, but with there being two, would also stay within the compressor map in the high RPM high mass flow rate region. (ie less 'lag' and broader torque curve)
two turbos running one after another = sequential setup. two turbos running next to each other - parallel.

stock mkiv supras = sequential setup

mkiv sequential turbos = one kicks in at around 2000 rpms and dies of at 4500 rpms, the other spinning up at 4500 to redline- hence the camel "hump" on the dyno graph typical for the stock mkiv.

most people think that the mkivs have a small and a large turbo, in reality they have 2 identical turbines, with different housings and a/r

now the rx-7 has also a sequential setup, but there both small identical turbos spool up at the same time thus striking balance between boost and lag

alex
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Well, ok, now, i know that the torque/power curve (it's basically the "same" thing) is important, but ultimatly I have to go with something I read when I started "knowing about" ICEs:

"It's better to make torque at high rpms than low rpms because you can advantage of gearing."

That 35d is amazing, yes, but it only revs to 5000rpms. The M5 gets 8000rpms.

This means that provided the gearing is set for the same max speed (this being, max speed in each gear), the M5 can have a 1.6x advantage from gearing (8000/5000). Let's say the 35d has a 1:1 ratio all the way to the wheels (fiction, it's never like this, but keep with me for now...).
AT the torque peak:
35d has 723Nm at the wheels. M5 would has 832Nm (520 * 1.6)

Outside the torque peak the values would be different, but the M5 would always have a more favourable gearing.

Two aditional things:
1. When you increase the rpm of a diesel it starts to be less like a diesel and closer to a gasoline engine. The fact is that diesel burns SLOWLY and thus it's hard to make high rpms because the fuel doesn't have enough time to burn (if you don't burn it, no power). Also, the high eficiency is reduced by the use of higher rpms because of frictional losses and because the p*v diagram get's further away from an ideal compression ignition cycle.

2. Although i never tested a 35d so can't say for sure, it probably suffers from the same as all diesels. 1st gear is useless! why? well, it's generally put there so you can start the car and let go of the clutch at 5km/h (auto equivalent is not to have the torque converter sliding for a lot of time from a dead stop). This means it makes way more wheel torque than the tires can handle. In fact, for a decently powered, manual turbodiesel, you can acelerate quickly (speed wise, not distance wise, and yes, there is a diference!) by starting from 2nd gear.

About speed wise vs distance wise, i think for now it's enough stuff, but if you want I'll write a post about it.
 

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AJ said:
two turbos running one after another = sequential setup. two turbos running next to each other - parallel.

stock mkiv supras = sequential setup

mkiv sequential turbos = one kicks in at around 2000 rpms and dies of at 4500 rpms, the other spinning up at 4500 to redline- hence the camel "hump" on the dyno graph typical for the stock mkiv.

most people think that the mkivs have a small and a large turbo, in reality they have 2 identical turbines, with different housings and a/r

now the rx-7 has also a sequential setup, but there both small identical turbos spool up at the same time thus striking balance between boost and lag

alex

few cars
Ah, i apologise, i wasn't aware of the supra running a sequential set up. I didnt think it had it after seing that the turbo's looked a similar size.
****, if id have know that i would have had more to research for my paper. :crying:

Sorry to drag this off topic, did they use a similar sequential set up in the R34 GTR skyline? Also was the sequential setup reserved for japanese or american spec supras? I'd never heard of it on any supras in england. It could be difficult to spot with the similar sized turbo's i spose.
 
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