The 2H/12H-T/1HZ/1HD-T/1HD-FT Gturbo Alternative Tech Thread (1 Viewer)

[Shrek80]

Do you have an after market waste temp gauge?

If you are seeing the OEM temperature gauge come up, you have a problem with your cooling system.

The number one issue with keeping a turbo'd 1HZ cool is having the engine fan clutch hub working in to top shape. If your fan hub is lazy, you're asking for trouble.
2nd issue is not enough boost or too much fuel.

Do you have a standard exhaust? Or upgraded?
That hero's with turbo performance and keeping things cool too

What i saw on that trip was before i had boost and egt gauges, more like 2 years back. It was the long hills where i noticed the (factory)temp gauge rise, and its always rock solid just below midway. It came up to maybe 6/10 instead of the usual 4/10. And returned as soon as cresting. I reckon my egt's must have been thru the roof passing that thru to the water.
I just have a saas boost and EGT. The sensor hole is drilled in the manifold just before the turbo.
Exhaust is 2 1/2". and as the truck is 6 metres long, its long! If i can sort a replacement turbo soon, then its likely ill need a new dump pipe to suit, so will look at the exhaust then.

 

[KiwiDingo]

That's why measuring EMP is so important, you can see that exact point when the turbo starts going out of its efficiency range for that fueling and boost level. It's the most important and useful gauge I've ever run when tuning and if more people started using one and learning about the massive effect high EMP has on engine performance and reliability I think you'll see a big reduction in engine failures

 

[Shrek80]

That's why measuring EMP is so important, you can see that exact point when the turbo starts going out of its efficiency range for that fueling and boost level. It's the most important and useful gauge I've ever run when tuning and if more people started using one and learning about the massive effect high EMP has on engine performance and reliability I think you'll see a big reduction in engine failures

Whats an emp gauge look like? Obviously not a plastic hose

 

[Shrek80]

Ah some copper line coiled up and a regular boost gauge. Maybe i could just use the egt tap and move the gauge around to get an idea.

 

[KiwiDingo]

I have a small coil of tubing to dissipate the heat before I hook up to the rubber hose going to my 30psi VDO boost gauge.

View attachment 2079479

 

[Shrek80]

Thats a nice looking manifold

 

[Shrek80]

So I just knocked up a line and stuck it in the egt port and connected my boost gauge in. So this is a bit rough as now I have no boost Gauge as a direct comparison. But it looks to be double. So emp hits a little over 25psi topped out where I have 13psi with the gate shut off.
Seems to track about where I’d expect accelerating.
So 2 to 1.
I could get used to watching that boost gauge spin right around

 

[Shrek80]

Reconnected the gate so it’s making 10psi tops. Dramatic affect on emp. It saw about 16psi topped out.
I’m gonna go buy a second boost gauge so I can better see what happens at various boost levels. And I will not be disconnecting the gate again..

 

[mudgudgeon]

third, it takes energy to create boost, so winding up the boost while keeping the fuel low will actually reduce overall power and efficiency

I don't think you have this point correct, maybe it's just the way I read it

Power and boost are heavily driven by the amount of fuel burnt.
Adding more boost with no more fuel should see a more complete fuel burn.
At that point, fuel efficiency is directly proportional to right boot input.

When I was messing around with a 1HD-T with CT26, increasing boost alone made almost no difference to power, no reduction, slight increase.

With the waste gate wired shut, peak boost was affected dramatically by fuel settings.

 

[mudgudgeon]

Seems to track about where I’d expect accelerating.
So 2 to 1.

There's definitely room for improvement.

Turbine is not efficient. If you have 25psi drive pressure to create 10psi boost, the turbo is basically a plug in your exhaust.

You should see somewhere between 1:1 and 2:1 (EMP : BOOST ratio) 1.5:1 is a good target.

High EMP adds to overheating issues, and high EGTs because the hot gases aren't getting away quick enough.
It also means the cylinder is probably not clear of exhaust gases as it draws in a fresh intake charge.

 

[mudgudgeon]

What i saw on that trip was before i had boost and egt gauges, more like 2 years back. It was the long hills where i noticed the (factory)temp gauge rise, and its always rock solid just below midway. It came up to maybe 6/10 instead of the usual 4/10.

This is dangerous territory.
The factory temp gauge is notoriously slow to respond in an overheat situation.
If you're seeing the gauge move that much, you are on the threshold of an engine killing overheat situation. Ask me how i know ( actually, don't )

I'd strongly recommend doing some reading about the fan clutch hub, and how to get the best performance from it.
With a tip top OEM fan clutch, you're far less likely to have overheating, unless there's issues with having a hot smokey tune.
Steer clear of aftermarket fan clutches. You will not beat the performance of a genuine fan clutch that is in good condition.

 

[Shrek80]

I actually rebuilt my entire air con in December. Pulled it all out, new pump and tx, seals etc. the guy who gassed it for me confirmed what I was going to do, re oil the clutch. But In knowing we were heading north in summer, he pushed me to stuff more oil in there than I was gonna.
the bugger fairly blows now!

 

[AussieHJCruza]

I actually rebuilt my entire air con in December. Pulled it all out, new pump and tx, seals etc. the guy who gassed it for me confirmed what I was going to do, re oil the clutch. But In knowing we were heading north in summer, he pushed me to stuff more oil in there than I was gonna.
the bugger fairly blows now!

In addition to the additional fluid, you can also adjust the point at which the clutch engages, for an easy solution strongly recommend the modified fan clutches from Wits-End @NLXTACY and @landtank - i had one on my turbo 1FZ and it was brilliant. What sort of condition is the radiator in? She should be able to shed the heat if the tune isn't stupid hot.

 

[Shrek80]

I replaced the radiator five years ago and all the rubber 2 years back with silicon.

 

[mudgudgeon]

I replaced the radiator five years ago and all the rubber 2 years back with silicon.

I'm a bit leary of silicon hoses. They can suck flat and restrict flow at higher RPM

 

[Shrek80]

Im wondering if the actuator spring in my turbo is setup for low pressure. I read specs that give an open pressure, and a beginning to open pressure. The high emp vs imp im seeing, could that be a product of a gate leaking boost too early? So even if blocking the vacuum to the actuator, the spring still dictates when it opens, and in its gradual manner right?
It is an old turbo, so im sure any near relative and new would surpass it easily. But i am keen to learn wabout the emp/imp and the manner in which the gate affects the relationship.

 

[mudgudgeon]

DTS use / used old turbo design, and tuned for 7-10psi was the normal "safe" tune.
There's been many a 1HZ killed by a "safe" 10psi, with a hot smokey tune

There are better options in terms of more modern turbo's that are more suitable for your engine.

Plus, boost is your friend. More boost, more airflow from a turbo that is working within its efficient range will give you more opportunity for power, while keeping EGTs lower

 

[Shrek80]

After adding up new turbo, intercooler (PDI) reco pump and injectors, I did start looking at other engine options. This truck will never leave me so figure on spending some money after all I’ve had it 16 years and most folk have had 2-3 cars in that time and blown money. She’s been kind to me.
It’s all a muchness tho, spend 6-7-8k on this motor, or sell it out and buy an old hdt or put a Barra or LS. It’s all about the same.
So I have figured I’d throw a new turbo at it first. If it showed signs of having more to offer then that’s the path. If not sell the turbo on and choose another route.
New turbo doesn’t need to blow my hair back but it does have to offer me some hope for it! One of the 1000 dollar mambas or et al would make my wallet happier too

 

[KiwiDingo]

Honestly the best and even more importantly the most cost effective solution in this case would be sending your current DTS turbo to Glenn at Munro Turbochargers. He'll totally transform your old tech turbo into one with the latest modern and highly efficient components which will then bolt straight back onto your current setup with zero changes.

 

[Shrek80]

I like the sound of that!