How much boost can 1HZ-T handle?

[Dougal]

This dyno plot is wrong:

Plotted 640Nm at 2050rpm and 138kw at 3,200rpm.

But 640Nm at 2050rpm would be 147kw.
The plotted power at 2,050rpm is ~107kw which is only 498Nm.

138kw at 3,200rpm is 411Nm, yet the chart is showing over 500Nm.

What is going on? Why do the plotted torque and power curves not match? Is power ground and only torque corrected?

 

[TheBigBoy]

This is a dynamics dyno. Run in shoot out mode. The reason for this is you can't frig with the numbers. All the info is on display in the box. Your math is just theory bull****.

 

[Dougal]

This is a dynamics dyno. Run in shoot out mode. The reason for this is you can't frig with the numbers. All the info is on display in the box. Your math is just theory bull****.

Nope.
The relationship between torque, power and rpm is pretty well established.

 

[TheBigBoy]

Like I've said. I don't doubt your knowledge at all. But the math has never lined up with reality. What you see is 100% legit. And this is why we will never agree. I could spend thousands on data logging everything at once. But there will always be something I'm sure someone will try and pick on. Go back to the first post and read the first run results.

 

[Dougal]

Like I've said. I don't doubt your knowledge at all. But the math has never lined up with reality. What you see is 100% legit. And this is why we will never agree. I could spend thousands on data logging everything at once. But there will always be something I'm sure someone will try and pick on. Go back to the first post and read the first run results.

When marketing doesn't match simple physics. The problem is almost never the simple physics.
In imperial power = torque x rpm/5252.
In metric power = torque x rpm/9550

Go back to your dyno operators and ask why power/torque/rpm don't match.
Ask them which figures are corrected, which ones aren't and how they are corrected.

If they can't explain it, then the credibility of the whole thing gets shaky.

 

[TheBigBoy]

I'll email you the number.

 

[Dougal]

I'll email you the number.

Why?
So I can do your job?

 

[Adam B]

in real life where would you see someone driving max boost and max EGTs for extended periods of time?

I drive for what I would call extended periods of time at max boost and max EGT regularly. That's bursts of several minutes at a time up the Fraser Canyon, 10+ minutes at a time on the Coquihalla. For me, that happens to be 23psi at the plenum and 1250-1300F with the probe centered right above the turbo entry. That's usually punctuated with a couple of minutes at 15psi and 1000F and then right back to max everything. Those are the conditions under which I did all my intercooler testing...full heat soak of the intake and exhaust sides.

For what it's worth, the length of my Isspro pyrometer probe can be adjusted. If one isn't careful, it's possible to end up with the tip barely protruding the tapped material of the manifold exit flange (way too shallow). I planned mine so the tip is dead center in the exhaust stream.

 

[TheBigBoy]

I wonder what your afr's are during that time Adam?

 

[Dougal]

I drive for what I would call extended periods of time at max boost and max EGT regularly. That's bursts of several minutes at a time up the Fraser Canyon, 10+ minutes at a time on the Coquihalla. For me, that happens to be 23psi at the plenum and 1250-1300F with the probe centered right above the turbo entry. That's usually punctuated with a couple of minutes at 15psi and 1000F and then right back to max everything. Those are the conditions under which I did all my intercooler testing...full heat soak of the intake and exhaust sides.

For what it's worth, the length of my Isspro pyrometer probe can be adjusted. If one isn't careful, it's possible to end up with the tip barely protruding the tapped material of the manifold exit flange (way too shallow). I planned mine so the tip is dead center in the exhaust stream.

Good to see someone gets it.
1300F is about 700C. Pretty much what I'd expect with a good tune in those conditions.

EGT probes are simply K type thermocouples. Available in a huge range of lengths and diameters. I have seen the same gauge bought in different places come with different length and diameter probes.
I run a 3mm probe for fast response. Even then it takes about a minute to read the true temp as the turbo and manifolds heat-soak.
I have a 6mm probe also. It was so slow to react that it sits in my spares box. On an acceleration run it wouldn't get halfway.

 

[TheBigBoy]

Ha ha, your claiming a win without even knowing what his afr's are doing. 600-700'c pre temps with a heat soaked manifold. Would you consider those temps safe and stable dougal?

 

[Dougal]

600-700'c pre temps with a heat soaked manifold. Would you consider those temps safe and stable dougal?

On a direct injection engine. Safe, yes.

I run 750C sustained myself. My Isuzu engine has seen 900C several times accidentally.

No idea what you mean by stable. If the manifold is heat soaked under sustained high load then of course it's a stable reading.

 

[TheBigBoy]

And what would you consider safe for IDI pre temps?

 

[Dougal]

And what would you consider safe for IDI pre temps?

650C sustained.

 

[TheBigBoy]

And what have you got for 3000rpm, 19.8:1, 85% IC efficiency (40 degree intake temps)?

 

[Dougal]

And what have you got for 3000rpm, 19.8:1, 85% IC efficiency (40 degree intake temps)?

Do I look like a magic 8 ball? I'm not here to answer all the question for a commercial enterprise intending to make money off the answers!

Find out for yourself.

 

[TheBigBoy]

Well your the first jump in and say "that's dangerous". Quoting numbers that are irrelevant. Bridging the gap between tech vs prac is difficult.

The reality is, it will never be driven to 4000rpm in real life. Not that you can't, but that you can feel the torque drop off and it just feels right to change at that point. This truck is not set up to tow, the owner just wanted to see how much reliable power he could make safely and drive it on weekends. So putting it under the same load as a dyno will be hard. And to compare it to other turbo HZ systems - they run 15:1 afr's.

 

[TheBigBoy]

Well your the first jump in and say "that's dangerous". Quoting numbers that are irrelevant. Bridging the gap between tech vs prac is difficult.

The reality is, it will never be driven to 4000rpm in real life. Not that you can't, but that you can feel the torque drop off and it just feels right to change at that point. This truck is not set up to tow, the owner just wanted to see how much reliable power he could make safely and drive it on weekends. So putting it under the same load as a dyno will be hard. And to compare it to other turbo HZ systems - they run 15:1 afr's.

 

[South]

Dougal, walk away, you have the experience and knowledge and can summarise politely. TBB will drag you down and down and down, and eventually he will be banned, as he has been on most of the Aussie Landcruiser forums... but hey I've got a ban on one of those sites too

To be fair, TBB has put in a fair effort, but usual antics... come on dude, put the crack pipe down!

My LC, tuned by THE MAN, pumps 610C POST turbo in 5th gear, starting at 110kph, slowing to 100kph at 6+tonne with camper attached up a 4km hill that is a 30% gradient... AFR is mid 19s, no noticeable smoke out the back (although mirrors were a bit dirty)... Would I do that again, probably not, but it was confirmed to be safe by THE MAN.

I love dyno read outs, there was a discussion on one just today, about needing a bigger exhaust, and the graph compared a stock car, to one with an upgraded exhaust... Apparently just adding a bigger exhaust gives you an extra 150Nm at 900rpm lower, yet only gives you an extra 4kw. That was some funny marketing!

 

[crushers]

no, you are here to help the mud brothers who might benefit from the question.
if you don't know the answer then just say so.

Do I look like a magic 8 ball? I'm not here to answer all the question for a commercial enterprise intending to make money off the answers!

Find out for yourself.