The Official 1HD-T/FT Fuel Pump Mod Tuning Thread

[asutherland]

Update!

I've completely solved my s***ty driveability issues.

1. Put the guide pin against a stock profile.
2. Increased main fuel screw (now that it wasn't overfueling due to the "modified" pin side)
3. Put a 6mm lock washer on the threaded section of the pin, below the diaphragm. Essentially on the diaphragm seat, as Ian suggested. I adjusted for the extra material on the threaded section by putting a narrower nut on the top. This is to compensate for the fact the pin I have is slightly shorter than a "stock" 93 1hdt pin.
4. Turned down the "smoke screw" height adjustment lobe on the top of the compensator. Now that the rod is essentially thicker, I don't need the lobe maxed out.

Result: Quick and responsive off the line, no pre-boost lag at all. No black smoke. Good throttle response and power throughout the power band. Reasonable EGTS (pre-turbo, under 1250 on full throttle up long hills, no intercooler)

Still have my idle/grey smoke issue, but I am sure that's to do with my ancient injectors needing rebuilding (possibly pump too). Going to talk with Okanagan Fuel Injection about that this coming spring.

 

[Tapage]

Spend sometime with the marvelous pin ..

retard little bit my overall timing since was advanced by my few years back and maybe little bit to much ..

 

[diby 2000]

I have been playing with my 1HD-FT setup. Its a stock auto with 330 kms apart from a safari intercooler and a boost T.
I have done the temp gauge mod, pre turbo egt, on board afr as well as pre (temporary) and post intercooler boost pressure.
I'm after a bit of clarification on the tune.

Is there a rev range the tune is set for?

I ask as I can only tune it to work perfectly at a specific range.
For example I have it tuned for perfect AFR (21:1) and EGT (750C) at 2000 to 2200rpm this is where I spend most of the time driving. As the revs increase the AFR slowly drops and consequently the EGTs rise. This continues as the RPM rises and eventually I can reach about 19:1 AFR and 850C EGT before I back off the loud pedal at about 3200rpm. By this point the boost is dropping from the 13psi (wastgate pressure) to about 11-12psi. I think my turbo is on its last legs and I assume this has an impact but I have also read that as the rpms increase there may not be enough time for complete combustion in the cylinder so the AFR and EGT gauges may be seeing this still burning mix entering the exhaust.

Am I on the right track or have I missed something?

 

[mudgudgeon]

Any tune is a compromise. The challenge is getting a tune to work across a broad rev range.

How much boost do you have at 2200rpm?
750c at 2200rpm is ok, but a bit on the high side.
You should still have strong boost beyond 3200rpm. More boost will keep EGTs down
Do the EGTs keep rising above 850?
Is the turbo stock?
Is the exhaust stock?

 

[AussieHJCruza]

If everything is working properly, you should be able to get the AFRs across t board reasonably consistent, with my current setup, from about 1800 up, AFRs are 20:1, and lean to 21:1 above 3000 t keep things cool. When I had the stock turbo, it was possible to get even across the board, but it meant pulling fuel out up top.

The stock turbo seems to start to choke above 3000 rpm, which means boost drops and EGTs rise but the boost compensator should be able, to a degree, to control this.

What is your timing at?

 

[Tapage]

If you are on stock exhaust, you will build more and more backpressure up to the range and that will kill some perfomance space ( tune ) up in the range ..

 

[diby 2000]

How much boost do you have at 2200rpm?

13psi. I was running up to 14 but on a grade with some altitude (>500m) at around those rpms the turbo makes an ugly scraping unballanced type of noise.

Do the EGTs keep rising above 850?

I'm sure they would if I stayed on the gas further up the rev range and the AFRs kept dropping

Is the turbo stock?
Is the exhaust stock?

Stock turbo with the wastegate spaced 3mm with a boost tee turned right down.
Taipan 3" exhaust with dump.

If everything is working properly, you should be able to get the AFRs across t board reasonably consistent, with my current setup, from about 1800 up, AFRs are 20:1, and lean to 21:1 above 3000 t keep things cool. When I had the stock turbo, it was possible to get even across the board, but it meant pulling fuel out up top.

That's what I was thinking. Hence my questions.

The stock turbo seems to start to choke above 3000 rpm, which means boost drops and EGTs rise but the boost compensator should be able, to a degree, to control this.

What is your timing at?

I don't think my turbo is too healthy as mentioned above to begin with.
Timing is set right on the advanced side of spec (sorry I set it but I cant remember).

One thing that is always in the back of my mind is that when I bought the truck back in 2006 with 200Kms, I was told the pump and injectors had just been overhauled. Yet when I checked the timing it was set to 1HD-T spec not 1HD-FT spec. I changed it to FT spec and the sound of the motor changed significantly. Sounds more like a 1HD-FTE than a 1HD-T. I have left it there ever since. Probably around 80kms.

 

[AussieHJCruza]

When my factory IP started to get tired, it manifested itself in very high EGTs at higher revs, evidently because the wear in the pump prevented it fro giving the dynamic advance required as the revs increase...could it be worthwhile getting your pump and injectors bench tested to see how they're performing?

 

[mudgudgeon]

If your turbo is making horrible noises don't leave it. Get it checked or replaced ASAP.
I can tell you what it sounds like when a turbo s***s the bed, and your engine swallows the pieces.

 

[AussieHJCruza]

X2, you don't want to a hear a 1HD-# at 6000+ rpm running on its oil because the turbo seals are feeding it into the intake...

 

[mudgudgeon]

X2, you don't want to a hear a 1HD-# at 6000+ rpm running on its oil because the turbo seals are feeding it into the intake...

I can tell you what that sounds like too listening to a 1hdt at 6000 plus rpm is fxxxen scary!! Stopping it is even scarier!

 

[diby 2000]

Thanks for the replies.
Kind of confirmed my fears.

New turbo first then pump and injectors.
They were all on the shopping list, just gotta follow the plan through.

 

[diby 2000]

If everything is working properly, you should be able to get the AFRs across t board reasonably consistent, with my current setup, from about 1800 up, AFRs are 20:1, and lean to 21:1 above 3000 t keep things cool.

Is your current setup a performance pump or stock with a tune?

I'm reading here and there that it is normal for the AFR to rise as the rpm increases with s stock pump setup as the timing advance does not go far enough.
I would think that a correctly setup pump (even stock) would deliver flat AFR but I am often wrong.

Just to clarify another point you made earlier, I have the compensation pin running on the flat for a bit at full boost to lean out the fuel after a more aggressive boost rise so the slight drop in boost doesn't change the fuelling.

 

[AussieHJCruza]

Is your current setup a performance pump or stock with a tune?

I'm reading here and there that it is normal for the AFR to rise as the rpm increases with s stock pump setup as the timing advance does not go far enough.
I would think that a correctly setup pump (even stock) would deliver flat AFR but I am often wrong.

Just to clarify another point you made earlier, I have the compensation pin running on the flat for a bit at full boost to lean out the fuel after a more aggressive boost rise so the slight drop in boost doesn't change the fuelling.

Current setup is an XXi pump, Gturbo BadBoy and so-on, on the stock pump we got pretty close to consistent AFRs

 

[diby 2000]

Awsome.
Thanks

 

[CycloSteve]

Anyone recognize this aneroid pin? It is the one which came with my OZ-spec 1HD-FT. Like the swapped-out turbo, I do not think that this is stock. Currently the profile is set just below max fueling on the pin.

 

[Tapage]

I didn't looks like my stock pin ..

 

[mudgudgeon]

I didn't looks like my stock pin ..

Agreed.
Looks very different to 1hdt pin. Not sure about 1hdft

 

[David60series]

I have been playing with my 1HD-FT setup. Its a stock auto with 330 kms apart from a safari intercooler and a boost T.
I have done the temp gauge mod, pre turbo egt, on board afr as well as pre (temporary) and post intercooler boost pressure.
I'm after a bit of clarification on the tune.

Is there a rev range the tune is set for?

I ask as I can only tune it to work perfectly at a specific range.
For example I have it tuned for perfect AFR (21:1) and EGT (750C) at 2000 to 2200rpm this is where I spend most of the time driving. As the revs increase the AFR slowly drops and consequently the EGTs rise. This continues as the RPM rises and eventually I can reach about 19:1 AFR and 850C EGT before I back off the loud pedal at about 3200rpm. By this point the boost is dropping from the 13psi (wastgate pressure) to about 11-12psi. I think my turbo is on its last legs and I assume this has an impact but I have also read that as the rpms increase there may not be enough time for complete combustion in the cylinder so the AFR and EGT gauges may be seeing this still burning mix entering the exhaust.

Am I on the right track or have I missed something?

I have found the exact same thing on a standard pump. AFRs at full load, foot buried run at 21 to 20 up to about 2900 rpm at at about 3000 I see a dip into the 19s and then all the way down to 17.2 at 3500rpm where I can see grey smoke in the mirrow but nothing too bad.

On the other hand at 3000rpm at full load up mountain range with trailer and say half throttle position she happy hums along at 25:1 and 500 degrees C post turbo.

Both scenarios are at 10 psi and my max boost is a smidgen under 11 psi.

I too am wondering if this is normal? Main Fuel set screw still has anti tamper from rebuild and all I have done is two clicks down on star wheel and turn aneroid pin to maximum ( was almost set at this point anyway).

 

[Nathjf88]

Been tuning my 1hdt over the weekend got my pre spool where it should be same with full boost afrs. I'm just trying to control cruise boost and how quickly it spools. She will spool very fast on the flat and a slide hill and it will hit full boost. What's the best way to control full boost on cruise ? Bring the spring tension up and drop the pin high with the smoke screw/off fuel boost ?

Setup ATM with 4 inch snorkel moonlight fab airbox gturbo badboy cross country ultimate intercooler stock pump with modified pin. Engine has lowered compression port matched and flowed head custom bowl pistons fully balanced.