Builds "The Cucumber" build. Ultimate 80-series. 1HD-FT, H152F (world's first), PTO. Titanium and carbon fiber galore. (1 Viewer)

[random101]

Sorry was the M8/M10 miss match to the transfer case?

Yep, ordered new bearings,shaft,clips! Was wondering if it needed anything else I can’t pinch from the h151 box

 

[TurboDennis]

Sorry was the M8/M10 miss match to the transfer case?

Yep, ordered new bearings,shaft,clips! Was wondering if it needed anything else I can’t pinch from the h151 box

Sorry, im still not sure which bolts you're referring to. Transfer case bolts up to H152 with the exact same bolts as to H151 (or A343 for that matter). The only bolts i recall being different are bolts for the transfer case shifter - if i recall correctly, those holes on H152 are M6x1 thread, and on H151 they are M8x1.25.

 

[Lo2aY]

Love the build and exotic materials. Not sure if it will be easy for you to do repairs and maintenance down the road with Titanium and composite. But please keep us posted on how it goes. I love trying new things.

About to start my FTE H152 swap on a carbed FZJ80.

I picked up a few things from here like the clutch master and transmission parts that need to be changed. Thank you very much for documenting this.

 

[fjbj40]

I see you went pre-turbo with your EGT probe.

Typically, for turbo safety reasons, probe is after the turbine.

Once you have seen a turbine that the probe failed and was ingested by the turbine you will see why.

 

[AussieHJCruza]

I see you went pre-turbo with your EGT probe.

Typically, for turbo safety reasons, probe is after the turbine.

Once you have seen a turbine that the probe failed and was ingested by the turbine you will see why.

For accuracy reasons probe is typically pre-turbo...

 

[fjbj40]

For accuracy reasons probe is typically pre-turbo...

And that’s fine for tuning only. Once past that I would post turbo it.

 

[AussieHJCruza]

And that’s fine for tuning only. Once past that I would post turbo it.

I've seen plenty of damaged engines due to high EGT/poor tuning.

I've never seen an EGT probe fail and go through the turbine.

Personally, the most accurate EGT possible is pre-turbo and that's where the probe is staying.

A damaged piston or internal component is most likely fatal for the engine. A damaged turbine is not.

 

[fjbj40]

I've seen plenty of damaged engines due to high EGT/poor tuning.

I've never seen an EGT probe fail and go through the turbine.

Personally, the most accurate EGT possible is pre-turbo and that's where the probe is staying.

A damaged piston or internal component is most likely fatal for the engine. A damaged turbine is not.

Temp drops across a turbine is linear.
Therefore once that is established post temps are just as accurate.

But to each their own.

Damaged engines from poor tuning is exactly that, poor tuning. If properly tuned then no issue arises. If the engine experiences something adverse then it will be too late, pre or post turbo probe.

But a failed probe from age/cycles will take out the turbo. Seen that.

Everybody has their way of doing things.

 

[AussieHJCruza]

Temp drops across a turbine is linear.
Therefore once that is established post temps are just as accurate.

But to each their own.

Damaged engines from poor tuning is exactly that, poor tuning. If properly tuned then no issue arises. If the engine experiences something adverse then it will be too late, pre or post turbo probe.

But a failed probe from age/cycles will take out the turbo. Seen that.

Everybody has their way of doing things.

I don't want to clutter up the thread or be argumentative, but from having had pre and post turbo EGT on a 1HDT in a HDJ80, on the same tune, I disagree in the context of a wastegated turbo fitted to an engine that doesn't run at constant speed.

At low rpm, high load (wastegate closed) I saw 200c+ lower temps post than pre, whereas at high rpm, high load (wastegate open) this variance narrowed, and likewise at constant rpm, constant load.

On the dyno, I could run pre-turbo from ~250c idle to 900c whilst the post-turbo gauge was still responding. Whilst I wouldn't send a customer's vehicle out the door with a tune like that, I also wouldn't send a customer's car out the door with post-turbo EGT.

Yes, EGT is only part of the equation, and in theory, if tuned to reasonable AFR, EGT isn't an issue, but timing, exhaust configuration etc. Will change EGT at the same AFR, so it's a useful tool, and IMHO, if a catastrophic probe failure happened, I'd rather replace a turbo than rebuild an engine.

YMMV

 

[ofer bruhis]

Temperature decay is nt linear, it's exponential! Basic heat transfer...

 

[fjbj40]

Temperature decay is nt linear, it's exponential! Basic heat transfer...

Discussion is not about temp decay. It’s about TIT vs EGT.

But let’s not clog Dennis’s thread please.

 

[TurboDennis]

Discussion is not about temp decay. It’s about TIT vs EGT.

But let’s not clog Dennis’s thread please.

I dont mind at all. Meaningful technical discussion is always welcomed in my thread.

As for EGT, i agree with the others - post turbo readings on these diesel engines are damn near useless, in my experience. I had an HDJ81 with a post turbo probe, and the readings were always highly inconsistent. Pre turbo is really the only option if you want accurate readings.

Probe failure might be a concern on high performance turbo gas engines, but DI diesels have MUCH lower EGT's, on average, so probes will last much longer. In any case, it's still a valid concern and i will probably add new EGT probe to a list of maintenance items to replace once every few years.

 

[ofer bruhis]

Temp drops across a turbine is linear.
Therefore once that is established post temps are just as accurate.

But to each their own.

Damaged engines from poor tuning is exactly that, poor tuning. If properly tuned then no issue arises. If the engine experiences something adverse then it will be too late, pre or post turbo probe.

But a failed probe from age/cycles will take out the turbo. Seen that.

Everybody has their way of doing things.

It is NOT linear. It IS a discussion about temperature decay. Going across the turbo is more even complicated than exponential decay because the flow is in motion, and also it hits the turbine, and there is heat exchange there as well. I have the background to support this...

 

[fjbj40]

Giddy up go daddy

I guess I’m not communicating correctly for what I’m trying to say.

Let’s try again.

My experience is based on education from Garret Airesearch and Pratt and Whitney.

One measures TIT as a reference and one measures EGT as a ref.

Turbine blades, generation I’m use to, have the same melting point.

One gives a caution at x temp in a reading of TIT.
The other gives a caution at x temp in a reading of EGT.

The temps both mean the same critical point yet they are split by several hundred degrees.

If you drop the temp 200 degrees pre turbine, TIT, then the temp after the turbine, EGT also drops 200 degrees.

Maybe you are an engineer, I’m not, I’m educated in my field when it comes to turbochargers and turbine engines from the manufacturer of the types I’m certified on.

What i originally said is EGT is just as effective as TIT for the purpose at hand and is safer.

Maybe linear was not the correct descriptor. My bad.

Cheers

 

[ofer bruhis]

Giddy up go daddy

Thanks. Have a great weekend.

 

[Feldrian]

nerd fight!

Thread delivers! 100%. Would recommend.

I even think i learned some things. I think that's what the tech forum is for.

 

[jaymar]

Has anyone actually run two sensors at the same time--before and after? That would be pretty conclusive.

 

[AussieHJCruza]

Has anyone actually run two sensors at the same time--before and after? That would be pretty conclusive.

Yes, the temperature drop isn't consistent, it depends on RPM vs boost vs engine load.

 

[ofer bruhis]

Yes, the temperature drop isn't consistent, it depends on RPM vs boost vs engine load.

And more. Outside temperature, ambient pressure and also humidity.

 

[Lo2aY]

I run the probe pre turbo on my builds. I've had one charge pipe fail mid-trip. and since the turbo is not spinning. The EGT was through the roof. I had to drive it slow to get it to be towed.

The EGT was at 1500F for extended times. The probe survived no issue.

I would recommend keeping it pre-turbo . It will be more accurate and the readings are not delayed.

My 2023 VDJ78 is getting 2 probes for each side. Also pre turbo.