landcruiser egt

[302 cruiser]

hi guys just put a pyro on my turboed 1hz was wondering what u guys recon about the egt how high should i let it go.

[dumbdunce]

did you search?

where is your thermocouple?

[302 cruiser]

yea i did a serch and i am guessing around 550 after the turbo where mine is just wanted to make sure.

also was wondering, my boost gauge is plumed into my waste gate actuator line do you think that would be acurate

[Gav75]

Mines post turbo too but in a 13B-T and the gauge reads farenheit Spelling???
I would be easing of the right foot at around 950F
you can do the conversion

Cheers.

[hilux79]

also was wondering, my boost gauge is plumed into my waste gate actuator line do you think that would be acurate

I wouldn't put my gauge there I would want it somewhere else in case for some reason that line got kinked or damaged caused boost to rise without you noticing. Pressure is an equal force in all directions so will be fairly accurate where it is but I'd prefer it off the manifold.

[dumbdunce]

yea i did a serch and i am guessing around 550 after the turbo where mine is just wanted to make sure.

also was wondering, my boost gauge is plumed into my waste gate actuator line do you think that would be acurate

that's probably safe. to get the best out of your engine and guarantee safe temperatures, move the thermocouple to the manifold before the turbine.

the wastegate actuator does not necessarily operate at manifold boost, it is better to move your boost gauge port to the inlet plenum.

[302 cruiser]

its showing 10lb boost its a ct26 off a 1hdt does that sound right

[302 cruiser]

I wouldn't put my gauge there I would want it somewhere else in case for some reason that line got kinked or damaged caused boost to rise without you noticing. Pressure is an equal force in all directions so will be fairly accurate where it is but I'd prefer it off the manifold

i cant see that happening

[Gav75]

its showing 10lb boost its a ct26 off a 1hdt does that sound right

Is that stock boost mate?

I have a CT26 on my 13B-T and stock was 8psi. I now have it at 12psi and it goes
much better. 14psi is about the max you want to go or you might blow the turbo.

If anyone is running higher boost than 14 please chime in.
It would be good to see what others are running.

Cheers,

Gav.

[302 cruiser]

yea havent tuched it. how would you blow the turbo running high boost

[dumbdunce]

its showing 10lb boost its a ct26 off a 1hdt does that sound right

factory boost for 1HD-T is 8 - 9psi, if the gauge is plumbed into the wastegate actuator hose it may read higher or lower than the actual boost - you will only know what your actual boost is if you plumb the gauge into the plenum

[dumbdunce]

yea havent tuched it. how would you blow the turbo running high boost

the more boost you run, the higher the forces on the compressor and turbine wheels. thrust forces especially will accelerate the wear of the thrust bearing, the turbine tries to drive the shaft into the centre and the compressor wheel tries to pull forward like a propellor. once the turbo starts working outside its efficiency envelope, these forces grow rapidly and the turbo will fail prematurely. it is not unknown for overboosting to cause the shaft to snap at the compressor wheel shoulder, although it is more common in petrol applications where snapping the throttle shut without adequate blow-off protection can cause massive boost spikes.

[Gav75]

what he said

[dumbdunce]

[
I have a CT26 on my 13B-T and stock was 8psi. I now have it at 12psi and it goes
much better. 14psi is about the max you want to go or you might blow the turbo.

.

I run my 1HD-FT at 15psi, I have had it as high as 20 for the dyno.

[Gav75]

I run my 1HD-FT at 15psi, I have had it as high as 20 for the dyno.

If problems were to occur from cranking up the boost is it likely that the engine
would blow or the turbo would fail? I spose if the turbo failed it would spit metal
through the engine. Do you think the 1HD-FT can handle higher boost pressures
than the 13B-T because it is a bigger engine?

I would like to increase boost but I'm a little cautious of killing my engine.

[dumbdunce]

I run my 1HD-FT at 15psi, I have had it as high as 20 for the dyno.

If problems were to occur from cranking up the boost is it likely that the engine
would blow or the turbo would fail? I spose if the turbo failed it would spit metal
through the engine. Do you think the 1HD-FT can handle higher boost pressures
than the 13B-T because it is a bigger engine?

I would like to increase boost but I'm a little cautious of killing my engine.

a short burst of high boost won't kill and engine or turbo, but sustaining it will. factory boost on the 1HD-FT is around 13psi, so 15 isn't much of an overboost.

[Gav75]

Yeah. I usually find around town if I'm giving it a bit of right foot it will peak at 12psi
then when cruising will drop back to 3 - 5 psi. On the highway, cruising in 5th and
doing 100k's, it will sit much higher (8psi or so) and it wont take much accelerator
at this speed to get to max boost. A slight incline or cruising at 110k's and its max
boost 12-13psi.

Does that sound normal? Is driving at 12 or 13psi for too long gonna hurt?

[ferrit]

my 1KZ-TE hits boost cut on the ECU at 15psi

[hilux79]

I wouldn't put my gauge there I would want it somewhere else in case for some reason that line got kinked or damaged caused boost to rise without you noticing. Pressure is an equal force in all directions so will be fairly accurate where it is but I'd prefer it off the manifold

i cant see that happening

Your choice but not hard to move and I have seen it happen where the diaphragm in the wastegate actuator leaked and let the boost rise past what it was set to and the gauge only showed a small increase when the gauge was moved to the manifold it showed a much larger increase.

[Tim HJ61]

I run my 12H-t at 14.5psi boost (which is the trigger point for the factory orange turbo overboost light) and the pyro pick up is pre turbo. I back off at 600°C, normally run to 500°C and have seen 700°C after a 1/4 mile drag <which gave me a bit of a startle> Standard boost 7psi. Also unwound fuel screw three turns

General performance is rather excellent. Discussion at http://www.perth4x4.net/forum/showthread.php?t=28202

For a long discussion, started by another West Aussie, on EGT, boost and more performance (focusing on a 12H-T) go http://forum.ih8mud.com/diesel-tech-24- ... build.html

Tim

[Z()LTAN]

i find it funny how people always relate EGT's with high Boost pressure.

EGT's are related to fuel mix


You can increase your boost to lower your EGT's people...

[302 cruiser]

what about advancing the pump timing what will that do to the egt?

[Tim HJ61]

i find it funny how people always relate EGT's with high Boost pressure.

EGT's are related to fuel mix


You can increase your boost to lower your EGT's people...

Of course we relate high EGT and high boost - if you've got your foot on the floor and going up a long hill, both will rise. But yes I agree by adding extra air you can reduce EGT. The point is; to what point is all this sustainable.

eg I'm running a stock CT26 on my 12h-t and have increased the fuel supply three turns and max boost to 14.5psi. If I disconnect the waste gate actuator I will hit 21psi turbo boost and yes, EGT will fall in the same operating conditions - but I really don't want to drive around punching 21psi from time to time. It actually boosts up to there really quite fast so I have drive very carefully to avoid punching up too high boost. Sure I have lots of power but it becomes a chore driving.

The whole aim of playing with boost and fuel supply is to get more power; we all have different level of tolerance on the risk we are prepared to take with the turbo and engine components.

This issue about EGT is not an exact science as far as I know, but am very happy to be educated about it. I don't mind running high EGT IF I am not doing any damage or reducing the reasonable running life of my motor. Is 900°C too much? - I'd guess probably it is. Is 800°C too much? etc etc. Is there a line we shouldn't cross???

Tim

[Z()LTAN]

600 pre turbo
550 post

they are the benchmark figures across most engines.

[dumbdunce]

what about advancing the pump timing what will that do to the egt?

leave the timing alone. more advance will probably cause knock (even if you can't hear it) and (even if you don't care) your NOX emissions will increase markedly.

[BIG12HT]

Running, extra fuel, more than 15psi in my 12H-T with CT26 turbo, clipped turbine, no other mods. 2nd gear of auto gives 133hp @ wheels as measured yesterday.

The clipped turbine was meant to be with many other mods and is not something I would reccomend as a turbo upgrade with no other mods or in fact for the way I have it set up now. having said that, I am happy to leave it as it is. It truly is a joy to drive.

Some smoke but not abnoxious, undoubtedly high EGT's.

From people who drive it they simply say "fantastic, it accelerates like a car"

From my experience of CT26 in stock form with 1HDT and 12H-T, if not intercooled, boost up to around 18psi is quite fine. However, if intercooling or adding big exhaust such things increase flow, these serve to increase turbine rpm and you push towards overspeed which can lead to bang and some bucks to be spent. The risk is an exploding compressor wheel and many of the bits going in the engine, the "compressor wheel fins" are very thin and positively fragile (half thickness) compared to a mitsubishi or Garrett equivalent. I have both wheels on my workbench, really no comparison. For their rated boost levels though, they offer better flow for the same size, albiet marginally.

As far as I am aware (and have been told by turbo rebuilders), thrust is not an issue so much for diesels because the thrust loadings occur during boost pressure changes and the diesel runs much closer to a steady state that a petrol equivalent. Auto's are even closer again. So, a petrol manual is the worst case scenario; Diesel auto being best.

In my high flow CT26 case (1HDT intercooled auto), I ran between 20-27psi with up to 640 deg C pre turbo after a long hill towing a caravan on my CT26 fitted to an intercooled 1HD-T for over 30,000km towing 90% of those kms and did not encounter a problem with the turbo. The car is still going srtrong, a family member has it now. It still had the stock 270deg thrust washer too.