It can be increased to 1.3 bars.
JFearne tuned diesels to run at this amount of boost with the M51 engine. It needs the right chip of course and preferably a larger intercooler. With this setup it should give 190-200bhp and 350Nm. The Mitsubishi turbocharger will not however maintain this amount of boost at higher rpm, it drops off. It is undersized for a chipped engine.
The MAP sensor just measures the manifold pressure. The chip mapping has a SVBL (Single Value Boost Limit) of 1.5 bars which is also about the upper limit of the sensor. If it goes over this it flips or defaults into limp mode. It can run at 1.3bars without triggering the limit.
Are you planning on fitting an external boost controller or just altering the turbo actuator rod?
Also if you are getting a boost gauge, get a diesel one not petrol which shows vac.
JFearne tuned diesels to run at this amount of boost with the M51 engine. It needs the right chip of course and preferably a larger intercooler. With this setup it should give 190-200bhp and 350Nm. The Mitsubishi turbocharger will not however maintain this amount of boost at higher rpm, it drops off. It is undersized for a chipped engine.
The MAP sensor just measures the manifold pressure. The chip mapping has a SVBL (Single Value Boost Limit) of 1.5 bars which is also about the upper limit of the sensor. If it goes over this it flips or defaults into limp mode. It can run at 1.3bars without triggering the limit.
Are you planning on fitting an external boost controller or just altering the turbo actuator rod?
Also if you are getting a boost gauge, get a diesel one not petrol which shows vac.
Langley wrote:
If you have any technical info on that I would be grateful.
I have a JFearne stage2 chip and Allisport intercooler. I have a current project to fit an external boost controller that should eliminate wastegate creep and a Garrett gt2256v turbo (as fitted to the M57 engine). Longer term to fit a higher pressure MAP sensor, maybe 2 bars. Trouble is the voltage outputs will be different so it will mean rewriting the chip. I am struggling with Winols at the moment.
If you have any technical info on that I would be grateful.
I have a JFearne stage2 chip and Allisport intercooler. I have a current project to fit an external boost controller that should eliminate wastegate creep and a Garrett gt2256v turbo (as fitted to the M57 engine). Longer term to fit a higher pressure MAP sensor, maybe 2 bars. Trouble is the voltage outputs will be different so it will mean rewriting the chip. I am struggling with Winols at the moment.
I am thinking about buy a p38 diesel, what sort of mpg do you get with a chipped engine if you drive it normally?
I have a allard vnt turbo at the moment fitted to my 300 tdi, do you think it would fit on the p38?
sorry for hijack
Slightly less than standard driven normally a lot less than standard driven hard. The only way to increase power on a diesel without major engine mods is to increase fuelling. More power, more fuel, less MPG. Simple physics. You don't get owt for nowt.
Datatek
Well-Known Member
Any torque boost will eat the gearbox
Can't believe people still ask this question. Dear sir i have a paraffin lamp. It is not quite bright enough to see by to do my needle point embroidery. But if i turn the wick up to give enough light it uses far too much fuel. How can i stop it doing that?
Datatek
Well-Known Member
Can't believe people still ask this question. Dear sir i have a paraffin lamp. It is not quite bright enough to see by to do my needle point embroidery. But if i turn the wick up to give enough light it uses far too much fuel. How can i stop it doing that?
Cracks the glass too:hysterically_laughi:hysterically_laughi
I asked the question because when I upped the fueling on my 300 tdi and fitted a bigger intercooler and a vnt turbo fuel consumption actually improved, it used to do 29-30 now it does 34 - 35mpg if driven "normally2 reason being there is so much more tourque that throttle openings are smaller for a given speed. I was asking for an experienced opinion from other p38 owners which sounds like that doesnt include youCan't believe people still ask this question. Dear sir i have a paraffin lamp. It is not quite bright enough to see by to do my needle point embroidery. But if i turn the wick up to give enough light it uses far too much fuel. How can i stop it doing that?
When will people stop reading advertisements and realise that plus 50 BHP and 100 lb feet of torque does not come by adding a couple of transistors and a selection of resistors and nothing else. You CANNOT have that AND better fuel economy it is not possible.
Datatek
Well-Known Member
There is a small improvement with a chipped auto due to fewer down shifts. Two years with a power box and two years with out and the difference in mpg is around .5mpg
If I booted it with the power box fuel consumption would drop like the proverbial stone
There is a small improvement with a chipped auto due to fewer down shifts. Two years with a power box and two years with out and the difference in mpg is around .5mpg
Yes that is true, but any auto is a slightly larger user of fuel anyway, they always have been. Many, even most, automatics in the past had up rated engines as compared to manuals of the same model. A P38 auto below 50 mph uses fuel for fun specially in stop start traffic around towns at 30 mph or less. On a good run or if you live in a country area with little traffic and open roads they are passable, but if you live in a hilly town or city and you do lots of short journeys be prepared to spend a little more on fuel. Fitting a chip in those areas and taking part in traffic light GPs will kill you.
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I can't believe people still think chips do anything more than increase fueling.
The standard derv mods are open up the fuel pump and turn up the turbo. All a chip does is open up the fuel pump (they trick the engine into thinking it is colder than it really is so runs rich to compensate). You will run rich at all times. You do not save money by doing that. Instead you just generate coal. If you're handy with a spanner you can do the same job as a chip for free. But honestly, there is no point. If the gain in power is less than ~10% you won't feel it (which those chips will never crack, the "feel" is all in your head), the over fueling will not give you +10MPG either. Just no, it will not happen.
The standard derv mods are open up the fuel pump and turn up the turbo. All a chip does is open up the fuel pump (they trick the engine into thinking it is colder than it really is so runs rich to compensate). You will run rich at all times. You do not save money by doing that. Instead you just generate coal. If you're handy with a spanner you can do the same job as a chip for free. But honestly, there is no point. If the gain in power is less than ~10% you won't feel it (which those chips will never crack, the "feel" is all in your head), the over fueling will not give you +10MPG either. Just no, it will not happen.
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No neither can i, but people still bang on about them. Ok the fuel map maybe a little more linear so if you drive like a nun on a long run or live in an open area, no hills no traffic and can maintain 50 plus MPH most of the time in an auto. You may just get a couple of MPG. But if you use the power you use the fuel simple as that.
But in conditions like that you're not going to be changing gears, so if you can lock in 4th with no slip, you'll use just as much if not less fuel. You're not making more power, you're only simulating more throttle.No neither can i, but people still bang on about them. Ok the fuel map maybe a little more linear so if you drive like a nun on a long run or live in an open area, no hills no traffic and can maintain 50 plus MPH most of the time in an auto. You may just get a couple of MPG. But if you use the power you use the fuel simple as that.
A better fuel saving device would be buttons to lock the box into a specific gear. At times round here I find it is too eager to drop into 2nd, could do with the ability to lock into 3rd. That'd save more fuel than any powerbox.
