Modern Turbo Diesel Power - Some might be interested.
19-06-2014, 08:25 PM
#81
Happily retired
. We need Graphs of these engine taken to the limits against a YB at the same.
You are comparing similar Power figures Stu why not try similar Torque figure where the YB will have 400+ more horses than that BMW at that torque level.
19-06-2014, 09:31 PM
#82
i think stu was talking about how far diseasal tech has progressed from when we all had dreams of a 400 brake cossie and would cream our pants at the thoughts of owning one 20 years ago 
ok, so you'd need to plough some serious wedge into getting a diseasal beemer in the first place with that engine, similar to what you'd probably have to pay for a nice saph, but 20-30 years of progress means you now get all the mod cons and several times the fuel economy for similar performance
30,000 psi is still boggling my mind
ok, so you'd need to plough some serious wedge into getting a diseasal beemer in the first place with that engine, similar to what you'd probably have to pay for a nice saph, but 20-30 years of progress means you now get all the mod cons and several times the fuel economy for similar performance
30,000 psi is still boggling my mind
19-06-2014, 09:43 PM
#83
Not all YB's are low Torque piles of shite Stu, that Escort graph is so bad i can name the Tuner .
We need Graphs of these engine taken to the limits against a YB at the same.
You are comparing similar Power figures Stu why not try similar Torque figure where the YB will have 400+ more horses than that BMW at that torque level.
. We need Graphs of these engine taken to the limits against a YB at the same.
You are comparing similar Power figures Stu why not try similar Torque figure where the YB will have 400+ more horses than that BMW at that torque level.
There is no real comparison simply because both platforms are so different and literally from different eras, but it's hard to argue at how impressive modern diesels can be.
Modern petrols can be good too, but there has been nowhere near the same improvements made with the two fuels.
20-06-2014, 08:26 AM
#85
The topic isnt really about "comparing" anything. It was just a topic intended to highlight the progress of turbo diesels to those members who still think of bomber taxis and mondeo 1.8 diesels. The Cosworth was used as the vast majority of people on here can associate with a T34 powered Cosworth but I could offer graphs from any number of cars you like as we don't do many cosworths on the Dyno compared to audis, BMW's etc but the majority of non ford stuff we do is diesel as that's where the market is nowadays.
Last edited by Stu @ M Developments; 20-06-2014 at 08:37 AM.
20-06-2014, 08:34 AM
#87
i think stu was talking about how far diseasal tech has progressed from when we all had dreams of a 400 brake cossie and would cream our pants at the thoughts of owning one 20 years ago ok, so you'd need to plough some serious wedge into getting a diseasal beemer in the first place with that engine, similar to what you'd probably have to pay for a nice saph, but 20-30 years of progress means you now get all the mod cons and several times the fuel economy for similar performance 30,000 psi is still boggling my mind
ok, so you'd need to plough some serious wedge into getting a diseasal beemer in the first place with that engine, similar to what you'd probably have to pay for a nice saph, but 20-30 years of progress means you now get all the mod cons and several times the fuel economy for similar performance 30,000 psi is still boggling my mindYou can buy a modern BMW with this engine installed for about Ł12k and it will perform like this everyday for 150'000 miles or more without any mechanical intervention bar an oil change every 12'000 miles. And it's USEABLE as the chassis was designed for it, no wheelspin and dangerous instability, just good reliable safe progress.
20-06-2014, 09:31 AM
#90
But thats just you showing off
What gains are made beyond certain paramiters though? There must come a point where the cost outweighs any potential saving?
And what about the risks involved should a pipe split? What sort of mechanicals need to be used to harness THAT much pressure? You could probably use it to forge diamonds!!!!
What gains are made beyond certain paramiters though? There must come a point where the cost outweighs any potential saving?
And what about the risks involved should a pipe split? What sort of mechanicals need to be used to harness THAT much pressure? You could probably use it to forge diamonds!!!!
20-06-2014, 10:20 AM
#94
Still not fun though, but the amount of pipe under that pressure is kept to an utter minimum and they are very over engineered fuel rails etc designed with that pressure in mind in the first place.
20-06-2014, 10:31 AM
#96
Interesting comparison, and TBH for a car for "fun" driving, I would pick the one with loads more revs on tap every time (especially as twice the revs means much more mechanical advantage so similar torque at the wheels where it matters of course), but for a daily its a no brainer that the BMW will be far more comfortable to potter around in.
20-06-2014, 11:24 AM
#97
PassionFord Post Whore!!
Pressure and flow are relative, the moment you had a rupture you would of course get a leak but the pressure wouldnt be maintained because of that, so the pressure would instantly drop very much lower.
Still not fun though, but the amount of pipe under that pressure is kept to an utter minimum and they are very over engineered fuel rails etc designed with that pressure in mind in the first place.
Still not fun though, but the amount of pipe under that pressure is kept to an utter minimum and they are very over engineered fuel rails etc designed with that pressure in mind in the first place.
the higher the pressure the more control you have in your system, but very few production systems go over 2500 bar yet as there is little need to (for the moment)
20-06-2014, 10:48 PM
#98
Advanced PassionFord User
Interesting comparison, and TBH for a car for "fun" driving, I would pick the one with loads more revs on tap every time (especially as twice the revs means much more mechanical advantage so similar torque at the wheels where it matters of course), but for a daily its a no brainer that the BMW will be far more comfortable to potter around in.
Stu, I'd love to hear some more about the mapping process (if you can give it away) and VNT turbocharger control and the relationship between fuel mapping and spool behaviour/harshness
20-06-2014, 11:31 PM
#100
this is pf as i remember it some proper technical articles to get my mind working, now im just nipping off to the muppet room to drop some iq before popping back in here for a top up. keep it up!
oh by the way those two stroke diseasels are really interesting too i like how they can just simply rotate and fire the engine in the opposite direction so they can reverse the boat, must be much easier than having a reverse gear lol
oh by the way those two stroke diseasels are really interesting too i like how they can just simply rotate and fire the engine in the opposite direction so they can reverse the boat, must be much easier than having a reverse gear lol
20-06-2014, 11:40 PM
#101
this is pf as i remember it some proper technical articles to get my mind working, now im just nipping off to the muppet room to drop some iq before popping back in here for a top up. keep it up!
oh by the way those two stroke diseasels are really interesting too i like how they can just simply rotate and fire the engine in the opposite direction so they can reverse the boat, must be much easier than having a reverse gear lol
oh by the way those two stroke diseasels are really interesting too i like how they can just simply rotate and fire the engine in the opposite direction so they can reverse the boat, must be much easier than having a reverse gear lol
21-06-2014, 01:49 AM
#102
i also had a moped years ago with a dodgy coil that intermittently upon backfiring would run (albeit poorly) backwards which was interesting to ride lol!
21-06-2014, 05:59 AM
#103
What you have to also consider is that some cars niw come with as many as 8 speed auto boxes, so they will maximise the shorter rev range and be in the "correct" gear more often
In a real world scenario even a lower powered diseasal will keep up once you factor in a petrol cars disadvantage with less gears going around the twisty bits, even with the luxury of having 3k more revs to the red line, youve still got a very similar actual power band now
In a real world scenario even a lower powered diseasal will keep up once you factor in a petrol cars disadvantage with less gears going around the twisty bits, even with the luxury of having 3k more revs to the red line, youve still got a very similar actual power band now
21-06-2014, 10:05 AM
#104
21-06-2014, 01:51 PM
#105
Regular Contributor
Depends on the vessel. Some still drive through gear boxes, a lot of larger vessels now have motor 'pods' with 360 degree rotation. The engine powering generators/alternators to drive the motors. Much the same way a diesel locomotive works. Engine powers generator, which powers the traction motors.
21-06-2014, 08:27 PM
#106
Advanced PassionFord User
possibly im just going off of something i read up about on two stroke motors the other week that highlighted one of the plus's of two strokes being able to run backwards and it mentioned one of the reasons being that some diesel boats ran backwards to reverse a prop
i also had a moped years ago with a dodgy coil that intermittently upon backfiring would run (albeit poorly) backwards which was interesting to ride lol!
i also had a moped years ago with a dodgy coil that intermittently upon backfiring would run (albeit poorly) backwards which was interesting to ride lol!
After that you get into medium and high speed diesels, which will have a gearbox by necessity, to reduce the 500-700pm crank speed down to shaft speed. These therefore normally have a reverse if on normal shafts.
If you go without conventional shafts, then you use Voith Schneider drives, or azimuth thrusters and things
After that you get more novel drive systems such diesel electric which are commonly used where there is a variable hotel load/propulsive load and it gives flexibility to manage both.
22-06-2014, 06:55 PM
#107
I've found that life I needed.. It's HERE!!
Off topic but most ships have controllable pitch propellers (CPP) whether it be conventional shaft or azimuth units, that way the engine or electric motor rotatates at a constant speed and blades on the prop pitch from ahead to astern.
23-06-2014, 01:55 PM
#108
Torque Vs Road speed.
Diesel.
On this test, 40-70mph = approx 1800rpm - 3400rpm
Cosworth.
On this test, 40-70mph = approx 3000rpm - 5200rpm
I.E:
Appropriate gear, put your foot down and see what power you have available to do the 40-70mph sprint for a relaxed overtaking maneuver?
Last edited by Stu @ M Developments; 23-06-2014 at 02:00 PM.
23-06-2014, 02:06 PM
#109
The problems tend to arise when people dont understand the relationship between diesel and heat and think adding MORE diesel will cool things down.
IE: they think smoke = safe when its the EXACT opposite.
Petrol tuning is almost the exact inverse to diesel tuning, so its more common to see screwed up diesel maps from tuners familiar with tuning petrol engines than it is the other way round.
Adding "A little extra for safety" is the little extra that destroys the turbos, cracks heads, cloggs DPF's etc. LOL
Last edited by Stu @ M Developments; 23-06-2014 at 02:09 PM.
26-06-2014, 05:25 PM
#111
Advanced PassionFord User
Im not totally certain what you mean, but I assume you mean like this...
Torque Vs Road speed.
Diesel.
On this test, 40-70mph = approx 1800rpm - 3400rpm
Cosworth.
On this test, 40-70mph = approx 3000rpm - 5200rpm
I.E:
Appropriate gear, put your foot down and see what power you have available to do the 40-70mph sprint for a relaxed overtaking maneuver?
Torque Vs Road speed.
Diesel.
On this test, 40-70mph = approx 1800rpm - 3400rpm
Cosworth.
On this test, 40-70mph = approx 3000rpm - 5200rpm
I.E:
Appropriate gear, put your foot down and see what power you have available to do the 40-70mph sprint for a relaxed overtaking maneuver?
To me that's real world fast, the same effect is repeated plus one gear if you like that sort of thing, but the wheel torque is what determines acceleration, the rest is sort of academic.
26-06-2014, 05:28 PM
#112
Advanced PassionFord User
The process doesnt differ very significantly from petrol to be honest other than the fuel ratios used and the fact we only really use boost to offset smoke. Spool cant be changed a great deal on a turbo diesel as they are technically on boost almost all the time and dont spin down and become lethargic like a petrol engine does because of course we have no throttle body impeding the turbochargers work.
The problems tend to arise when people dont understand the relationship between diesel and heat and think adding MORE diesel will cool things down.
IE: they think smoke = safe when its the EXACT opposite.
Petrol tuning is almost the exact inverse to diesel tuning, so its more common to see screwed up diesel maps from tuners familiar with tuning petrol engines than it is the other way round.
Adding "A little extra for safety" is the little extra that destroys the turbos, cracks heads, cloggs DPF's etc. LOL
The problems tend to arise when people dont understand the relationship between diesel and heat and think adding MORE diesel will cool things down.
IE: they think smoke = safe when its the EXACT opposite.
Petrol tuning is almost the exact inverse to diesel tuning, so its more common to see screwed up diesel maps from tuners familiar with tuning petrol engines than it is the other way round.
Adding "A little extra for safety" is the little extra that destroys the turbos, cracks heads, cloggs DPF's etc. LOL
How does the injection timing work relative to a petrols ignition timing? From what I gather with diesel being a slow burning fuel you run into issues with injecting enough fuel, fast enough to get it al to burn properly without removing the valves....
26-06-2014, 08:37 PM
#113
Interesting comparison, and TBH for a car for "fun" driving, I would pick the one with loads more revs on tap every time (especially as twice the revs means much more mechanical advantage so similar torque at the wheels where it matters of course), but for a daily its a no brainer that the BMW will be far more comfortable to potter around in.
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27-06-2014, 06:41 AM
#115
Yeah kind of, except youd need to have run the cossie a gear lower to make it fair I suspect. Basically select your best overtaking gear for passing some cretin doing 40 and work out what torque is available at the wheels from there to 70 To me that's real world fast, the same effect is repeated plus one gear if you like that sort of thing, but the wheel torque is what determines acceleration, the rest is sort of academic.
We run cossies in 3rd gear on the Dyno but to illustrate your point about choosing peak torque for overtaking, using these same graphs, just tweak your speed to 50 - 80mph. With the two chosen graphs, the diesel can stay in the same gear anyway with no detriment at all (4th) and the cossie will now be in its peak torque area.
Last edited by Stu @ M Developments; 27-06-2014 at 06:43 AM.
27-06-2014, 07:40 AM
#116
PassionFord Post Whore!!
Biggest bit of bodgeeneering I ever saw was on a friends car. He purchased a nice E60 530d and I was discussing remaps with him. I said to only go for a decent remap from a reputable company and he agreed a few days later, his impatience and tightness got the best of him and he made an ebay purchase Ł30 ‘tuning box’
He fitted it himself and reported back that it had made ‘some improvement’ to the car, not that it needed any really (I have an E39 530d and its plenty quick in standard trim).
A few weeks later he wanted to do his swirl flaps and having done mine I said I would lend him a hand, so he brought the car to mine, when we were working on the engine he showed me the tuning box and it was a little plastic box with a couple of plugs that went inline with the common rail pressure sensor, and I can only assume that it intercepts the rail pressure signal, changes it and returns it to ECU making the engine think the rail needs more pumping and overpressurising the rail to inject more fuel, no consideration for boost pressure, EGR, DPF or the affect it may have on injector, rail and engine life.
That evening in the pub I explained exactly why this would be problematic and he removed it shortly after.
Shows how people can be suckered into buying something as its cheap, but the problems you could end up with are catastrophic, especially when a decent considered remap is only a couple of hundred pounds!!!
He fitted it himself and reported back that it had made ‘some improvement’ to the car, not that it needed any really (I have an E39 530d and its plenty quick in standard trim).
A few weeks later he wanted to do his swirl flaps and having done mine I said I would lend him a hand, so he brought the car to mine, when we were working on the engine he showed me the tuning box and it was a little plastic box with a couple of plugs that went inline with the common rail pressure sensor, and I can only assume that it intercepts the rail pressure signal, changes it and returns it to ECU making the engine think the rail needs more pumping and overpressurising the rail to inject more fuel, no consideration for boost pressure, EGR, DPF or the affect it may have on injector, rail and engine life.
That evening in the pub I explained exactly why this would be problematic and he removed it shortly after.
Shows how people can be suckered into buying something as its cheap, but the problems you could end up with are catastrophic, especially when a decent considered remap is only a couple of hundred pounds!!!
27-06-2014, 07:54 AM
#117
A guy at work has a tunig box on his A4, made it from 140bhp to 170 so he claims.
when he was looking for a remap i told him to go get a proper one from a reputable tuner, but he is a penny pinching tight cunt and went for the cheap option.
to be fair to it tho, its been on a year or more now and he reckons he is getting better mpg and more power!
if ever get my A3 130bhp done, there is a revo dealer on my doorstep, or an MSD etc map. i wont use a tuning box.
when he was looking for a remap i told him to go get a proper one from a reputable tuner, but he is a penny pinching tight cunt and went for the cheap option.
to be fair to it tho, its been on a year or more now and he reckons he is getting better mpg and more power!
if ever get my A3 130bhp done, there is a revo dealer on my doorstep, or an MSD etc map. i wont use a tuning box.
27-06-2014, 10:46 AM
#118
Advanced PassionFord User
Totally agree, that's my real world measure too.
We run cossies in 3rd gear on the Dyno but to illustrate your point about choosing peak torque for overtaking, using these same graphs, just tweak your speed to 50 - 80mph. With the two chosen graphs, the diesel can stay in the same gear anyway with no detriment at all (4th) and the cossie will now be in its peak torque area.
We run cossies in 3rd gear on the Dyno but to illustrate your point about choosing peak torque for overtaking, using these same graphs, just tweak your speed to 50 - 80mph. With the two chosen graphs, the diesel can stay in the same gear anyway with no detriment at all (4th) and the cossie will now be in its peak torque area.
and 3600-5750 for the petrol where its producing (barring one bump), 325 or less
The diesel uses 1400rpm to accelerate where the petrol uses 2150rpm, so the difference in the gear ratios (net, including tyre size, final drive and the actual gear you're in) is 1.53.
Dividing the diesel down by the 1.53 results in 333ftlbs equivalent which is more than the petrol, but even better than that, the petrol is off boost at the start of the overtake and has another 1250rpm to pull at the end. The diesel is also out of puff by the end, but could have pulled out at 1800rpm in the same gear to no ill effect (38mph)
What this all boils down to is a more flexible car requiring fewer gear changes and delivering more performance on average and retuning better economy, the only downsides being that it sounds crap and doesnt 'feel' fast as there is no off/on boost wall like you get with the petrol, you just watch the needle winding round relentlessly.
27-06-2014, 01:00 PM
#119
Advanced PassionFord User
if you're talking about curves, area under the graph then a well put together roots charged petrol engine is hard to beat. It's just the heat kicked out that can make them a pain.
This is a 1.6 engine with a ported big valve head, stock compression (which is very low due to supercharger) and a wild'ish cam (270/278 @ 10mm). Boost would be around 14psi I expect, makes 240 at the wheels
This is a 1.6 engine with a ported big valve head, stock compression (which is very low due to supercharger) and a wild'ish cam (270/278 @ 10mm). Boost would be around 14psi I expect, makes 240 at the wheels