2.7 Turbo Diesel engine Tips

[Terrano-saurus]

Here is some general random infomation for anyone that wants it:

EXHAUST TEMPS
MAX of 570c under load for short periods
EGT’s of 535c after turbo are safe temperatures, even for sustained running, mile after mile.
EGT’s above 535c after turbo are getting dangerously high.
Lowering intake temperature (INTERCOOLER) results in an almost equal reduction in exhaust temperature.

Leaning out the A/F ratio on a diesel will just give you less power.
Running a diesel rich will produce lots of smoke, more power and make it run hot!!

Turbo boost - 14psi is an extremely safe psi to have the boost at on a stock diesel engine with big intercooler and free flowing exhaust (you can run 16psi to 18psi safely)

Always run a min of 12 psi – because the lower the boost the richer the mixture needs to be and the richer the mixture the hotter the EGT’s

[Terrano-saurus]

Pyrometer should be mounted just after the start of the exhaust pipe where it bolts onto the turbo approx 100mm to 150mm down from flange (toward the muffler)

Hope the above info helps you guy's out and saves a few headaches

[Patrolling Paddy]

Is this info aimed at ALL diesels?
Where did the info come from?
Who or what have you got to prove all this?
What effect does it have on longevity?

Not trying to be a smart arse but with details such as this it is a big call with no proof/documentation.
I have been told by some speed shop hero that my TD42 will safely run on 20psi all day no probs and can handle 32psi is small doses but it was just his word and he had nothing to back it up, so lets just say I'm not going to be a guinea pig and mine will stay on 12psi till I can be provided proof.
If what yor saying is true then bring it on lets get some more shetland's out of the big girl. LOL

[Bricki]

Is this about the 2.7 in the older Terrano ??

Sounds a bit risky - speshly what paddy said about 20psi all day long in his patrol - ouch, sounds like a disaster waiting to happen

[Terrano-saurus]

I understand where you are coming from, some of this info is from my direct experience and some is from forum members of another 4x4 site here in OZ, all info that I aquired has been researched four fold so as to ascetain what is factual and what is fiction, I have driven trucks for over 20 years with turbos and I have a vast mechanical knowledge having repaired numerous engines, diffs, etc. 12psi in a diesel engine is very conservative you could ask a turbo diesel specialist to comfirm this, the main thing is to keep the exhaust gas tempreture under about 550 degrees celcius while the engine is under load the above tempreture is taken from the exhaust pipe not the exhaust manifold. longevity should not be effected as long as the EGT's are kept under 500c most of the time. I have also been told that 20 & 30psi is safe to run but can not confirm this and therefore I will not go above 15psi myself. yes this info pertains to most diesel engines (maybe not the new ecu type) I will keep you guy's posted in the future and inform you as to the outcome of my setup, running at 14psi.

Is this info aimed at ALL diesels?
Where did the info come from?
Who or what have you got to prove all this?
What effect does it have on longevity?

Not trying to be a smart arse but with details such as this it is a big call with no proof/documentation.
I have been told by some speed shop hero that my TD42 will safely run on 20psi all day no probs and can handle 32psi is small doses but it was just his word and he had nothing to back it up, so lets just say I'm not going to be a guinea pig and mine will stay on 12psi till I can be provided proof.
If what yor saying is true then bring it on lets get some more shetland's out of the big girl. LOL

[Terrano-saurus]

Yes it is a 1993 terrano, I will not run 20psi but 14 psi with an intercooler and keeping the EGT's under 500c I dont have any concern with.

Is this about the 2.7 in the older Terrano ??

Sounds a bit risky - speshly what paddy said about 20psi all day long in his patrol - ouch, sounds like a disaster waiting to happen

[Peter @ Aawen4x4]

Paddy (& Bricki if you're interested), Terrano-saurusses post IS all fairly generally applicable knowledge that applies to most diesel engines, and is pretty much on the ball for all of the pre 3.0 litre Di Nissan engines! I simply don't know enough about the 3.0l Di engines yet to confirm that it all applies to them, but I'd guess it's gonna be pretty close!

And I think that we all should avoid running boost pressures over about 12-15 psi if we have the slightest interest in engine longevity!! 20 to 30 psi is generally recognised as possible but not conducive to reliability, although some people seem to survive pretty well, but I'm not sure that it's 'cos the engine survives for that long or the whole car get's destroyed early from being driven so hard before the engine gets a chance to die!

Running a Patrol engine with these parameters isn't going to make it a rocket, but it will make it a comfortable drive and give you a chance of getting reasonable fuel economy and reliability while still doing better than most diesel 4WD's in the Traffic Light Grand Prix, but if you've got a GU, you'd probly get almost as much gain by going over the vehicle with a spanner and taking off all the extra bits and bolts that aren't being used for anything!! Every time I get to work on a GU I run into a hundred or so bolts doing nothing, just there either waiting for something that isn't fitted to this model, or 'cos they used to put something there 10 years ago and it's still catered for in the assembly line!! I took off a whole 20l bucketful without really trying last time I looked!

Enjoy!

[terra88]

Hey all, I also have a terrano, 1988 2door. I run 15-16psi boost and have a PWR glycol cooler kit, 3 inch exhaust etc etc. My pyro reads about 650 degrees at 15psi under load, more if towing or uphill and less if crusing. A mate also has a terrano but runs identical pyro temps but runs less boost and no cooler. As for cooler affecting temps ?? don't think it has much bearing as the amount of fuel from the injector pump controls most of the temp as you stated about too much fuel makes it run hot. Also if fitting the pyro probe after the turbo it can reduce the temp reading by approx 200 degrees, fitting between head and turbo is the ideal place.

[Patrolling Paddy]

Hey all, I also have a terrano, 1988 2door. I run 15-16psi boost and have a PWR glycol cooler kit, 3 inch exhaust etc etc. My pyro reads about 650 degrees at 15psi under load, more if towing or uphill and less if crusing. A mate also has a terrano but runs identical pyro temps but runs less boost and no cooler. As for cooler affecting temps ?? don't think it has much bearing as the amount of fuel from the injector pump controls most of the temp as you stated about too much fuel makes it run hot. Also if fitting the pyro probe after the turbo it can reduce the temp reading by approx 200 degrees, fitting between head and turbo is the ideal place.

I'm assuming that your pyro is pre turbo? I'm not expert but if your getting 650+deg post turbo you must be getting close to a melt down.
I think that the I/C allows more air with less boost (air density) and more boost with less air temp, then the exhaust temps can be altered by the fuel mix.
The boost gauge pick up on your rig is it before or after the I/C?

[Terrano-saurus]

Good to see it works for you I will feel better about running mine at 14psi. Also is your psi reading taken from the original spot on the turbo or after the intercooler.

Hey all, I also have a terrano, 1988 2door. I run 15-16psi boost and have a PWR glycol cooler kit, 3 inch exhaust etc etc. My pyro reads about 650 degrees at 15psi under load, more if towing or uphill and less if crusing. A mate also has a terrano but runs identical pyro temps but runs less boost and no cooler. As for cooler affecting temps ?? don't think it has much bearing as the amount of fuel from the injector pump controls most of the temp as you stated about too much fuel makes it run hot. Also if fitting the pyro probe after the turbo it can reduce the temp reading by approx 200 degrees, fitting between head and turbo is the ideal place.

[terra88]

Hey mate the boost guage is hooked up after the intercooler..

[Terrano-saurus]

Thanks

Hey mate the boost guage is hooked up after the intercooler..