Tapage
Club 4X4 Panamá
I usually coast 800°F about 100km/h over 24 AFR last time I check ..
The Official 1HD-T/FT Fuel Pump Mod Tuning Thread (7 Viewers)
- Thread starter ForealBoreal
- Start date
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on a 1HDFT pump, can I take out the fuel push rod, leave in the connecting pin and lever control spring and drive it to set the maximum AFR? or will the connecting pin and spring drop into the pump somehow? Mine has auto transmission and TPS, so the plug on the front of the pump to take out the connecting spring and pin is awkward to get to.
Cheers
Cheers
SeaJay, yes you can.
Connecting pin will just push out, giving max fuel position. Its even mentioned in a certain tuning instruction as an option.
Just remember you'll need to put a taper on the bottom of the fuel pin to re-insert it, opposite side to the profile you are using for your fuel control. Hope that makes sense.
Ignore all the guf on this picture, but described where to put the taper on the bottom, but make it almost full width
Connecting pin will just push out, giving max fuel position. Its even mentioned in a certain tuning instruction as an option.
Just remember you'll need to put a taper on the bottom of the fuel pin to re-insert it, opposite side to the profile you are using for your fuel control. Hope that makes sense.
Ignore all the guf on this picture, but described where to put the taper on the bottom, but make it almost full width
Thanks Dan, that pic is worth saving.
Cheers
Cheers
Hi all, no need to taper the pin to put it back in, simply undo the bolt in front of the pin and remove the spring, push follower pin back and slide fuel pin in, replace spring and do up bolt, simple. May need to pump primer a couple of times to remove air. Cheers Tom
Tom my pump has the TPS mounted on the side so its a pain to get to that plug, chamfering the pin works well for me, it pops back in quite easy now.
Whilst you are correct Tom.. i find even without the TPS, getting a spanner, socket or my big clumsy fingers onto that little bolt is a bit tricky... and the chamfered pin is the go
Dont read too much into the text on that picture... it was when i was playing around with some ideas 3+ years ago
Dont read too much into the text on that picture... it was when i was playing around with some ideas 3+ years ago
Ok what ever works.
I have a question, my 1hdt uses 18l/100k. It should only be about 12 or 13. Somebody fiddled with pump b4 I bought it, just trying to get back some economy now. My thoughts that the star wheel has been wound down too far, so that even cruising with low boost it sits deep in fuel pin. Does not blow excessive smoke at all.
Today I will set the boost compensator back to factory settings then go from there.
I believe the main fuel screw is ok as any adjustment down the power drops(won't pull the hat off your head)
Any thoughts?
I have a question, my 1hdt uses 18l/100k. It should only be about 12 or 13. Somebody fiddled with pump b4 I bought it, just trying to get back some economy now. My thoughts that the star wheel has been wound down too far, so that even cruising with low boost it sits deep in fuel pin. Does not blow excessive smoke at all.
Today I will set the boost compensator back to factory settings then go from there.
I believe the main fuel screw is ok as any adjustment down the power drops(won't pull the hat off your head)
Any thoughts?
You could tighten the star wheel (bring it up) say 10 clicks and see what that does. If its not blowing excessive smoke... that tends to indicate the star wheel position is ok.
What other mods have been done to the vehicle... tyre size, weight, accessories, driving style etc all play a part in economy.
What other mods have been done to the vehicle... tyre size, weight, accessories, driving style etc all play a part in economy.
A very stock hdj80.
I wound the star wheel up today, made it very slow off the mark until it reached 1800rpm then was good. Turned the cam on top 1/4 turn, seems to go ok now. Will fill up tomorrow and see how the economy goes on the next tank. Tom
I wound the star wheel up today, made it very slow off the mark until it reached 1800rpm then was good. Turned the cam on top 1/4 turn, seems to go ok now. Will fill up tomorrow and see how the economy goes on the next tank. Tom
Well my economy is still lousy at 18l/100k. My other hdj80 gets 12l/100k. Both pretty stock.
Anybody got any suggestions? Tom
Anybody got any suggestions? Tom
- Thread starter
- #392
@Planesmaker
There could be multiple culprits why your truck is getting bad fuel economy.
Hopefully as a basic your air/fuel filters are clean. Sticking brakes. Add ons could be a big reason why you have poor economy (big tires/roof rack)
Injectors and pump could be tired or in need of a service. The injectors are a big one.
The star wheel adjustment can decrease or increase smoke under load depending how you have it set. The cam plate can fix the bottom end.
Every truck is different. Its not all that hard to tune but to really know whats going on preturbo egt is a great starting point. AFR is even better for the tuning process.
There could be multiple culprits why your truck is getting bad fuel economy.
Hopefully as a basic your air/fuel filters are clean. Sticking brakes. Add ons could be a big reason why you have poor economy (big tires/roof rack)
Injectors and pump could be tired or in need of a service. The injectors are a big one.
The star wheel adjustment can decrease or increase smoke under load depending how you have it set. The cam plate can fix the bottom end.
Every truck is different. Its not all that hard to tune but to really know whats going on preturbo egt is a great starting point. AFR is even better for the tuning process.
mudgudgeon
Resident galah
How fresh are injectors?
Have you checked pump timing?
Have you checked pump timing?
Fuel and air filters good, checked timing, not sure when injectors were done. Brakes not dragging, same tyres as the other truck, no rack. Burns clean too.
Plansmaker ,Sorry for your economy wows . I'm thinking it's a while before you need this' pump mod thread.' Might get more wide range help if you start your own thread about your specific issues.
Hi,
Have read and absorbed the majority of these 20 pages. I have a 1HD-T I've just started some tuning on am looking for some confirmation of my understanding.
Motor is stock other than 3.5 inch dump pipe and 3in mandrel exhaust. Fresh injectors and fresh pump rebuild set to factory specs (there was no on car tuning).
Motor is a slug and slow to spool up turbo since pump rebuild. I anticipated this, as it had been tweaked prior and I knew it would be slower.
Have pyro/boost fitted. Have AFR gauge but not presently fitted.run 11psi boost, no intercooler.
Questions:
1) have rotated aneroid pin to 'maximum' and turned down star wheel 3-4 clicks CW. Big improvement. Much faster spool up and low end response. Minimal smoke. Would like a bit more off idle response; should I try the star wheel a little further down before I touch the cam/starting position on top of the aneroid?
2) in relation to the above, does the stop screw adjustment then add pre-load to the spring; therefore requiring it be turned down more?
3) am I on the right track to adjust the stop screw last, or should I turn it to maximum to get the most travel and play with star wheel?
4) all the guides say that once full boost comes in, the aneroid pin has no affect on fueling, but is the factory profile still limiting fuel at full boost?
5) if, after fitting AFR gauge, I make any adjustment to to the main fuel screw; do the aneroid settings need to be revisited?
6) if I gained HP on the dyno after the previous tweak; did the tuning mob play with the max fuel screw, or can max HP increases be made through energies setting only?
Have read and absorbed the majority of these 20 pages. I have a 1HD-T I've just started some tuning on am looking for some confirmation of my understanding.
Motor is stock other than 3.5 inch dump pipe and 3in mandrel exhaust. Fresh injectors and fresh pump rebuild set to factory specs (there was no on car tuning).
Motor is a slug and slow to spool up turbo since pump rebuild. I anticipated this, as it had been tweaked prior and I knew it would be slower.
Have pyro/boost fitted. Have AFR gauge but not presently fitted.run 11psi boost, no intercooler.
Questions:
1) have rotated aneroid pin to 'maximum' and turned down star wheel 3-4 clicks CW. Big improvement. Much faster spool up and low end response. Minimal smoke. Would like a bit more off idle response; should I try the star wheel a little further down before I touch the cam/starting position on top of the aneroid?
2) in relation to the above, does the stop screw adjustment then add pre-load to the spring; therefore requiring it be turned down more?
3) am I on the right track to adjust the stop screw last, or should I turn it to maximum to get the most travel and play with star wheel?
4) all the guides say that once full boost comes in, the aneroid pin has no affect on fueling, but is the factory profile still limiting fuel at full boost?
5) if, after fitting AFR gauge, I make any adjustment to to the main fuel screw; do the aneroid settings need to be revisited?
6) if I gained HP on the dyno after the previous tweak; did the tuning mob play with the max fuel screw, or can max HP increases be made through energies setting only?
mudgudgeon
Resident galah
Cheers.
Stop screw; I was referring to cam adjustment on top of aneroid. I am assuming this is always the last thing to fine tune? I just wondered how much effect it had one the spring pre-load and part of the pin profile that was being utilised.
When I got tuned some years back, the dyno readout claimed a gross hp gain from approx 100 to 117hp and improved torque. They noted aneroid mods, but I'm assuming the max fuel screw may have had adjustment. Prior to this tune, it went really well but blew a bit of soot off the mark (assuming previous owners tweak).
My pyro temps currently remain very similar to what I witnessed under any tune I have had. Full load up hills at 100km/h will see 550c 50 mm after turbo.
Rule of thumb, should I continue to turn down star wheel and monitor smoke?
Assume I have done the right thing and started with 'maximum' pin profile.
Unsure if I should start with 'minimum' cam setting for off boost of if any position is as good as any to start with?
Thanks again for your help! I'm from a petrol/carby background so treading gently with this.
My truck is 3.5t for average trip in 40c ambient temps so I smoke chasing a very safe and reliable tune.
Stop screw; I was referring to cam adjustment on top of aneroid. I am assuming this is always the last thing to fine tune? I just wondered how much effect it had one the spring pre-load and part of the pin profile that was being utilised.
When I got tuned some years back, the dyno readout claimed a gross hp gain from approx 100 to 117hp and improved torque. They noted aneroid mods, but I'm assuming the max fuel screw may have had adjustment. Prior to this tune, it went really well but blew a bit of soot off the mark (assuming previous owners tweak).
My pyro temps currently remain very similar to what I witnessed under any tune I have had. Full load up hills at 100km/h will see 550c 50 mm after turbo.
Rule of thumb, should I continue to turn down star wheel and monitor smoke?
Assume I have done the right thing and started with 'maximum' pin profile.
Unsure if I should start with 'minimum' cam setting for off boost of if any position is as good as any to start with?
Thanks again for your help! I'm from a petrol/carby background so treading gently with this.
My truck is 3.5t for average trip in 40c ambient temps so I smoke chasing a very safe and reliable tune.
mudgudgeon
Resident galah
Some of the guys playing with custom aneroid pin grinds don't utilise the top screw. It simply changes your starting point on the aneroid pin. I'd start with it at min and optimise things as much as you can before looking at the main fuel screw. If you have too much smoke off boost or as it comes on boost, you can reduce the main fuel screw setting.
With standard aneroid rod, adjusting the cam fine tunes your off boost fuel, it doesn't change max fuel.
More fuel equals more heat and more potential energy.
increasing fuel can also increase boost or gjve an opportunity to increase boost.
increasing boost a few psi can reduce EGTs considerably too.
Increasing fuel and boost will give greatest gains in power. Increasing boost alone (if there's enough fuel to burn) will improve EGTs and economy.
Keep an eye on EGT and AFR readings and you're pretty safe although I'd seriously consider shifting the EGT probe pre-turbo, as it is, you're left guessing.
It's easy to lose track of what you've changed, but after a while you'll figure out what's what and it doesn't really matter.
With standard aneroid rod, adjusting the cam fine tunes your off boost fuel, it doesn't change max fuel.
More fuel equals more heat and more potential energy.
increasing fuel can also increase boost or gjve an opportunity to increase boost.
increasing boost a few psi can reduce EGTs considerably too.
Increasing fuel and boost will give greatest gains in power. Increasing boost alone (if there's enough fuel to burn) will improve EGTs and economy.
Keep an eye on EGT and AFR readings and you're pretty safe although I'd seriously consider shifting the EGT probe pre-turbo, as it is, you're left guessing.
It's easy to lose track of what you've changed, but after a while you'll figure out what's what and it doesn't really matter.
when you had the pump rebuilt did they wire up the max fuel screw with a lead security seal? if so, and now its been removed, then I would guess that when you had it tuned they upped the max fuel. (If so it would be nice to set the max fuel first with an AFR meter.)Start with minimum on your cam adjuster, set your spring tension (not too soft or it will over fuel and overheat in top gear at low revs) then if needed, small adjustments down on the cam (on top of the boost compensator) to give it a bit more off the line pre boost. At 11psi you shouldn't have to grind the fuel pin, that's only when you run high boost and add more fuel, and need to raise the pin to reduce fuel at low rpm
