Help with tuning 1HD-T by AFR (1 Viewer)

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Jun 30, 2013
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Hi,

Have HDJ80 for 8 years looked after like an only child. Have monitored EGT readings over past six years.

Had a pump rebuild a while back with no 'on car' tuning so it's stock. CompAred to previous tunes it is gutless but I want to do it myself this time. Have read everything I can get my hands on. It's got nothing off the line. Ok once ~5psi boost comes in but still slow to what it can be.

Has 3inch exhaust and I have rotated aneroid pin to maximum profile, but it wasn't far off this position. Off boost screw was in maximum when it came back from pump rebuild. Have left star wheel for interim.

AFR is above 99:1 at idle and only 24:1 at full load I.e. Fifth or 4th gear WOT up hill 100km/h. I have seen a quick dip towards 21 from memory for a split Devine at 3000rpm in 3rd.

Running stock 11psi at manifold.

Pyro is post turbo. I drive to keep it below 500 with alarm on 550 and off 500. It's a heavy rig, but I usually see ~400 -450 at 100km/h on flat in 30 degree weather. Hit the alarm overtaking and up hills easily - probably worse on the lean tune this power tune!

Want to aim for 20:1 to begin with. My theory is to get this reading is to set main screw 1/4 turn in ir about 1.5cc I think and go from there. Leave aneroid adjustment to end to eliminate smoke or add more low boost fuel if smoke allows.

Generally high EGT for me or 'high risk driving' is at 100km/h so I tend to think AFR and EGT at 4th/5th 2200 - 3200 is important.

Main two questions:

1) what rpm/gear is best for AFR test?
2) will 1/4 turn be good starting point?

I KNOW this engine can make great power. Have experienced it. Just want it back safely and bit happy with answers it questions Bout EGT Abe AFR from 'tuners' I have called.

Injectors Are in good order - 80 000km since reco. Good fuel and filters always used.
 
Interesting question.

I'll be going down this path soon with a turbo'd 1hz.
Had previously given my 1hd-t a pretty good tweak.

My approach would be to tune it to EGTs I'm happy with, then tweak using AFRs. EGTs will give you a rough and ready indication of the tune.

I'd be shifting the pyro to pre turbo, post turbo is too questionable.

1/4 turn from stock is not a huge increase, but it's definitely a good starting point, especially given your description of it being gutless. you can always dial in more fuel. 1/4 turn should see improved boost and response. More boost will also keep EGTS in check.
Stock boost should be up around 13-14psi.


AFR at idle is irrelevant IMO. Adjusting the idle speed is basically adjusting the fuel delivery at idle to get an engine speed your happy with.
You'll most likely need to tweak the off boost setting and idle speed each time you change the main fuel screw.

What gear you use to see max EGTs or AFR doesn't really matter. 4th gear is easier to load up the engine for a WOT run starting from as close to idle as yiu can

it takes quite a bit of tinkering to get a good grip on the relationships with all the settings. It can be a never ending obsession
 
i'm hopping to start down this path soon too. how are you measuring afr? i have a digital gauge that'll read it but where do you put the sensor on this engine. i'm new to diesel tuning but want to learn. thanks and hope this isn't hijacking your thread. please document what you do and your results because ill be follow along with hopes of doing this soon too. just need to get the different sensors installed (they are on my bench) before i start tinkering.
 
AFR will just be via MTX-L and exhaust clamp.

pyro is post turbo only because the port on beau exhaust is already there at dump pipe. Don't have a port on turbo or manifold that I am aware of on HDJ80R?

The port is within 50mm of outlet and probe is in middle of 3.5 inch dump.

Understand it's not as good, and in my opinion doesn't hold a steady max like pre turbo but it's still a reference.
 
Its not tho. Post turbo is essentially useless on these motors. It takes all of 30 minutes to drill and tap the manifold and add a probe pre-turbo. No disassembly required.

That would be my absolute first step before anymore tuning, get on it!
 
I'd have to agree with above, seems very few use AFR's for tuning these things, pre-turbo EGT is key.
 
if you have access to Dyno and you are willing to modify your pump, timing and follower pin .. then AFR it's a great path ..
 
Hey OP,

I'm running an ISSPRO Pyrometer pre-turbo (middle of exhaust manifold). I'm looking to dial in a tune, so I'm adding an Innovate MTX-L Wideband 02 sensor this Friday and then I'm going to hunt down a dyno shop in town.

I'll echo what everyone else has said so far - anything downstream from the turbo is useless if you're looking to get realtime accuracy from your pyrometer. Mount your wideband 02 in your downpipe and tap a hole in your exhaust manifold for the EGT sensor.
 
I'd have to agree with above, seems very few use AFR's for tuning these things, pre-turbo EGT is key.

Fellas like dougal or gerg might be able to clarify this, but my understanding (I'm a builder, not a diesel tuner :hillbilly:) is that your pyro gauge will give a decent, but rudimentary indication of what is going on with combustion, fuel settings, and timing, but it's not the full story.

EGTs at the manifold/pyro will vary depending on the injection timing (if all else is equal).
Retarded timing will see higher EGTs as combustion happens later and is still occurring on the exhaust stroke and in the exhaust port/manifold and therefore closer to the pyro.
Advanced timing should see lower EGTs as combustion is more complete within the cylinder, and gases will be cooling (not burning) as they pass the pyro.

AFR will tell you more precisely what the fuel mixtures are doing. AFRs, plus EGTs used together let's you further fine tune fuel delivery volume and injection timing.
 
How do you prevent bits of drilled out manifold dropping and going through the turbine with out doing it on the bench!? I would be too worried!
 
The manifold is cast iron so drilling and tapping swarf is small granules. 99% will come back out the hole as you drill. Put some grease on the drill and tap to catch another .5%.
Leaves a tiny little bit of swarf falling into the manifold which just passes through the exhaust on start up
 
How do you prevent bits of drilled out manifold dropping and going through the turbine with out doing it on the bench!? I would be too worried!

I used grease on the bit, and started the engine when breaking through and tapping to blow any bits out. Worked great, albeit a little nerve wracking while you're doing it.
 
Drill it here...
1HD-FT EXHAUST MANIFOLD.jpg
 
@franklin40
You need a wide band O2 sensor, and suitable gauges, such as the Innovate mentioned above
You can either weld a bung into the exhaust 18" or more from the turbo for a permanent install, Or put a sensor up the tail pipe for tuning

thanks. i do have a system that could read on O2 sensor, id just need to put one in the down pipe then. thanks for the clarification on where to put it and whats needed to do so. i think i'll pass on doing this for now. boost and EGT is where i'll start. I'm not looking for race tuned engine trying to pump out every spare horse i can. just want to get a better tune for towing. i bought the zetronix system and have boost gauge and egt probe. just need to install these first. thanks for the sidetrack info guys.

agree with the idea of drilling with he truck running around 2000 rpm. this should blow out shavings. alternatively a small extendible magnet down the drill hole should also clean out shavings if you do it with the engine off.
 
thanks. i do have a system that could read on O2 sensor, id just need to put one in the down pipe then. thanks for the clarification on where to put it and whats needed to do so. i think i'll pass on doing this for now. boost and EGT is where i'll start. I'm not looking for race tuned engine trying to pump out every spare horse i can. just want to get a better tune for towing. i bought the zetronix system and have boost gauge and egt probe. just need to install these first. thanks for the sidetrack info guys.

agree with the idea of drilling with he truck running around 2000 rpm. this should blow out shavings. alternatively a small extendible magnet down the drill hole should also clean out shavings if you do it with the engine off.

Boost and EGT are what 90%+ people seem to use for tuning these trucks. The only times I've seen AFR data is when tuning on the dyno.
 
Hi,

Have HDJ80 for 8 years looked after like an only child. Have monitored EGT readings over past six years.

Had a pump rebuild a while back with no 'on car' tuning so it's stock. CompAred to previous tunes it is gutless but I want to do it myself this time. Have read everything I can get my hands on. It's got nothing off the line. Ok once ~5psi boost comes in but still slow to what it can be.

Has 3inch exhaust and I have rotated aneroid pin to maximum profile, but it wasn't far off this position. Off boost screw was in maximum when it came back from pump rebuild. Have left star wheel for interim.

AFR is above 99:1 at idle and only 24:1 at full load I.e. Fifth or 4th gear WOT up hill 100km/h. I have seen a quick dip towards 21 from memory for a split Devine at 3000rpm in 3rd.

Running stock 11psi at manifold.

Pyro is post turbo. I drive to keep it below 500 with alarm on 550 and off 500. It's a heavy rig, but I usually see ~400 -450 at 100km/h on flat in 30 degree weather. Hit the alarm overtaking and up hills easily - probably worse on the lean tune this power tune!

Want to aim for 20:1 to begin with. My theory is to get this reading is to set main screw 1/4 turn in ir about 1.5cc I think and go from there. Leave aneroid adjustment to end to eliminate smoke or add more low boost fuel if smoke allows.

Generally high EGT for me or 'high risk driving' is at 100km/h so I tend to think AFR and EGT at 4th/5th 2200 - 3200 is important.

Main two questions:

1) what rpm/gear is best for AFR test?
2) will 1/4 turn be good starting point?

I KNOW this engine can make great power. Have experienced it. Just want it back safely and bit happy with answers it questions Bout EGT Abe AFR from 'tuners' I have called.

Injectors Are in good order - 80 000km since reco. Good fuel and filters always used.
What are you using to read 99:1 AFR. All the ones I found are maxing out at 24:1 or even 40:1?
 
I’m thinking of getting off of these AFR meters


Vs


Apps look identical.

As per performance electronics:

“The sensor that you can use is a Bosch Wideband A/F Sensor part number 17212. You can use the sensor that comes with the PE-Wideband Kit, however the sensor element will get clogged from the soot in the diesel exhaust. The sensor from the part number I sent you has a different design for a diesel that will not get clogged.”
 

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