- Thread starter
- #1,141
I played with a cummins lid on my boost compensator as it gave far more adjustment than that cam.
Did the trick for my old truck
Did the trick for my old truck
The Official 1HD-T/FT Fuel Pump Mod Tuning Thread (10 Viewers)
- Thread starter ForealBoreal
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
Bolt on, or needs some massaging to fit? Any specific engine/year models to pilfer from?
I have the same lif as Seajay but haven't installed it yet as I'm still running without an intercooler so adding fuel tends to increase my EGTs too much. Cranking up my star wheel really helped because I think I had been just over fueling and then hitting the fuel cut. My wideband is still in the box too so hopefully one of these days I can get it on. I feel like when I started tuning mine when I put my stock pin in it was riding on the ramp even before boost and currently I have the smoke screw can set to allow the pin to be higher and my off boost fuel is still a bit rich so I would like to get my cap installed and see if I can get that set better.
In my pic you can see the line from turning the pin around.
Last edited:
That pic looks like you're getting deep into the fuel cut portion of your fuel pin?
@vwluv10338 Did you get the cover directly from Trundles Automotive in NZ, or did you find a vendor state-side? Looks like the price is currently $130 NZD, not including shipping, etc...thus my looking at more economical solutions (Zexel or Cummins).
Agree that it looks like you too could benefit from raising the off-boost starting point of the pin, and perhaps keeping out of the fuel-cut.
@IanB
In my defense that pic is from last year when I first started messing with it. I pulled the pin today and it looks like it's using much more of the pin taper. Since the pic was taken I have cranked up the star wheel quite a bit.
@CycloSteve
I ordered it straight from Trundles along with his least aggressive pin so I could grind on it if I wanted to.
In my defense that pic is from last year when I first started messing with it. I pulled the pin today and it looks like it's using much more of the pin taper. Since the pic was taken I have cranked up the star wheel quite a bit.
@CycloSteve
I ordered it straight from Trundles along with his least aggressive pin so I could grind on it if I wanted to.
- Thread starter
- #1,147
It was simply a from a VE pump cummins which off the top of my head was 90 to like 96. Dont quote me on that though. Direct bolt on.
Simply put guys figure out your star wheel setting to get you to right on the edge of the ramp on your pin.
See where it travels with your boost level, how are your egts or afrs if you monitor that.
Increase your star wheel tension (unscrew out of housing)if you want to raise your afr level at full load or decrease your egts
Decrease your star wheel tension (turn into the housing)to decrease your afrs or increase your egts ar full load.
Once you are happy with fueling settings, temps, and performance you play with the smoke screw on the lid.
The smoke screw tunes the performance off the line. It will be a balance of what smoke and power you the driver finds acceptable.
Everyones tuning will be a bit different depending on preference and driving style.
This probaly wont make sense until you start tinkering with it and it will dawn on you. Its a simple yet time consuming process. Dont be scared of doing half a turn or full turn on the star wheel. Once you set the edge of the ramp youll have to fine tune it and it will probably be on the slope when you are done.
Here are a few more detailed pictures with measurements of my pin.
Last edited:
OK, secured a Cummins/Bosch cover and wondering what folks did to plumb the boost line. The port is an 8mm x 1.0 thread, so assume a simple brass barb would work...but wonder if any sort of restrictor should be used as the Denso reference line barb has a tiny passage/hole.
Also I see that some folks in the Cummins world grind off the step around the screw itself to allow for higher movement of the pin. Any thoughts before I bust out the Dremel?
Also I see that some folks in the Cummins world grind off the step around the screw itself to allow for higher movement of the pin. Any thoughts before I bust out the Dremel?
- Thread starter
- #1,150
I kept mine stock and fitted an 1/8 barb to it.
Did the job
Did the job
I've had some dirty diesel thru my pump and pulled it to have it checked out at the diesel shop. The feed pump rattles like crazy.
Now since it's out, i might do some mods anyway....
Any thoughts on or experience with higher lift camplates? Such as fitting a 2.8mm or 3.2mm lift Cummins 6BT camplate? Would this help keeping the exhaust clean under no or low boost circumstances? I already fitted a different pin and a Trundles boost cover.
My goal is to have around 300-325 hp at the crank. Maybe a little more
This is on a 1HDFT
Any insight would be helpfull
Thanks!!
Now since it's out, i might do some mods anyway....
Any thoughts on or experience with higher lift camplates? Such as fitting a 2.8mm or 3.2mm lift Cummins 6BT camplate? Would this help keeping the exhaust clean under no or low boost circumstances? I already fitted a different pin and a Trundles boost cover.
My goal is to have around 300-325 hp at the crank. Maybe a little more
This is on a 1HDFT
Any insight would be helpfull
Thanks!!
mudgudgeon
Resident galah
Do you know what the lift on the 1HD-FT cam plate is?
1HD-FT already had a more aggressive cam plate. It's capable of delivering something like double the fuel of a 1HD-T pump.
1HD-FT already had a more aggressive cam plate. It's capable of delivering something like double the fuel of a 1HD-T pump.
Ok, i wasn't aware of that. I'll have the dieselshop measure the plate for me and then i'll know.
- Thread starter
- #1,154
Set the flow to the amount of CCs you want.
Roughly 1cc per 2hp at the wheels is the formula roughly
Roughly 1cc per 2hp at the wheels is the formula roughly
Thanks! I didn't have the most helpfull dude at the diesel specialist, so this helps.
A bit more work today. Ground the lip down on the Bosch cover, and installed the barb. Now have a bit more upwards travel with the pin.
Smoke at idle is down, but without adding a restrictor to the line, the boost comes on too quickly. Purchased two Subaru "restrictor pills", one 1mm and the other 1.2mm, and will see how those slow the buildup of boost passing to the diaphragm next week.
Smoke at idle is down, but without adding a restrictor to the line, the boost comes on too quickly. Purchased two Subaru "restrictor pills", one 1mm and the other 1.2mm, and will see how those slow the buildup of boost passing to the diaphragm next week.
Last edited:
just picked up a 92 hdj81, it has a little trouble cold starting, stumbles some and sometimes dies after a few seconds on the first try. I'm thinking i need to adjust the injection pump a little, i was planning on tuning it some anyway but haven't added a EGT gauge yet. am i on the right track? i think its a little lean, smokes a little at idle but i don't see smoke when i am driving which makes me think its lean.
mudgudgeon
Resident galah
You should see very little smoke, even when it has a performance tune.
Diesels typically run "lean". Power is controlled by the amount of fuel injected, opposite of a petrol.
For a 1HD-T, you should see a puff of smoke when you stab the throttle at idle, or from coasting to accelerate, beyond that, smoke will rarely be visible.
Your starting issue could be related to injector condition, or pump timing.
Diesels typically run "lean". Power is controlled by the amount of fuel injected, opposite of a petrol.
For a 1HD-T, you should see a puff of smoke when you stab the throttle at idle, or from coasting to accelerate, beyond that, smoke will rarely be visible.
Your starting issue could be related to injector condition, or pump timing.
thanks, im reading through lumpskie's build thread, he had a similar cold start issue. I've contacted him to see what fixed it. this is my first diesel so I'm learning as i go, its all stock at 320,000km. hopefully its something i can fix myself. from what I've read most of the star wheels need to be adjusted from factory so that was my first thought.
