The Official 1HD-T/FT Fuel Pump Mod Tuning Thread (9 Viewers)

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Diameter is 10.9mm.

Can 4130, 4140 be hardened? Standard pin is case hardened and polished
I think this message confirms the 10.9mm diameter for the stock 1HD-T

I don't recall if anyone has confirmed that 1HD-T and 1HDFT pins can be interchanged.

can anyone confirm?
 
Here is the stamp on my pump. so it being a VE6/12F1 means its a 12mm pump does that mean I need the 11.9mm one?

12mm refers to the diameter of plungers on the distributive head.

AFAIK all HD-T series Denso pumps use a 10.9mm aneroid pin, but would be best to confirm with Trundles before ordering.

The larger pins are for Bosch VE pumps
 
12mm refers to the diameter of plungers on the distributive head.

AFAIK all HD-T series Denso pumps use a 10.9mm aneroid pin, but would be best to confirm with Trundles before ordering.

The larger pins are for Bosch VE pumps
Thanks I actually took mine out and measured the diameter. It’s 10.9mm

When I pulled mine out the grind looked not right to me. its as if half of it was ground down at a 90 degree half the pin is missing
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Hi, guys seeing if there's any benefit to running High flow injectors +30% aka Gturbo and others. VS the stock standard configuration.

any benefit to running high flow on a stock VE pump or even with an upgraded fuel pin.

or what should be expected with VE pump upgrades?
 
I never saw a benefit .. stock ( healthy ) injectors are very capable .. with a healthy Fuel pump, proper tunned fuel pin I had plenty fuel available across the range ..
 
Hi, guys seeing if there's any benefit to running High flow injectors +30% aka Gturbo and others. VS the stock standard configuration.

any benefit to running high flow on a stock VE pump or even with an upgraded fuel pin.

or what should be expected with VE pump upgrades?

Ideally, you want pump and injectors to be matched.
Running a high flow injector without increasing pump /injector crack pressures doesn't make sense to me.

More flow through a nozzle will see lower injection pressure. Try adjusting flow through the nozzle of your garden hose. If the hose tap/faucet is turned on full flow, More flow through the nozzle = less pressure, and coarser spray. Less flow through the nozzle = more pressure, finer spray.

Later model HD-T series engine updates (late HD-T, HD-FT, HD-FTE) all had increasingly higher injection pressures to atomize fuel better. Finer atomization means better efficiency, more complete fuel burn, more power, cleaner combustion.

If your pump is customised to produce more flow, AND more injection pressure, then high flow injectors make sense provided the address set to work with the pump
 
Ideally, you want pump and injectors to be matched.
Running a high flow injector without increasing pump /injector crack pressures doesn't make sense to me.

More flow through a nozzle will see lower injection pressure. Try adjusting flow through the nozzle of your garden hose. If the hose tap/faucet is turned on full flow, More flow through the nozzle = less pressure, and coarser spray. Less flow through the nozzle = more pressure, finer spray.

Later model HD-T series engine updates (late HD-T, HD-FT, HD-FTE) all had increasingly higher injection pressures to atomize fuel better. Finer atomization means better efficiency, more complete fuel burn, more power, cleaner combustion.

If your pump is customised to produce more flow, AND more injection pressure, then high flow injectors make sense provided the address set to work with the pump
What exactly needs to be done to increase flow in the pump. Is this something someone can diy with the right tools and parts?
 
What exactly needs to be done to increase flow in the pump. Is this something someone can diy with the right tools and parts?

You're beyond the realm of DIY for that.

Once tuning maxes out the original pump's capabilities, it needs to be upgraded by a pro and tested on a flow bench.

Depending on what pump you have, increasing flow and pressure will be through changing distributive head and plungers from 11 to 12mm
 
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Sounds good looks like I’ll be saving for some pump and injector upgrades in the near future.
 
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I never saw a benefit .. stock ( healthy ) injectors are very capable .. with a healthy Fuel pump, proper tunned fuel pin I had plenty fuel available across the range ..
in your experience, early 1hd-t injectors are good until what HP range?
 
ill post this here as it can affect the IP, for quite a while when I opened the fuel cap air would suck in, the tanks were under vaccume, at times it was so bad I thaught the fuel filter was partialy blocked. I had pulled the fuel cap appart as I thaught that was vented, looks like it only lets pressure out. There is a tank vent line with what I believe is supposed to be a one way valve amongst the fuel lines neer the tank change over solinoid and brake proportioning valve, with the valve secured to the body, and the tail end of the line going into the chassis thru a grommet. I changed the valve with a small in line fuel filter and now no more tank vaccume :)
 
Hi all, I’m after a 1hdft boost pin, can anyone help or direct me to a site to even obtain an aftermarket one ?
Thanks
Trundles Automotive out of New Zealand. They also sell a taller cap and various springs.
 
Hey all I been playing with my pump timing and have a oil leak from the seal which mates to the timing cover. (The little band seal) so I have this ready to fit).
While I pull the pump out is it worth replacing the one I have circled also ? Does it just pop out the from easy enough ? Just making sure it does not fit from the inside of the pump and need a major strip down.
Thanks

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Just found a local AUS guy wth an interesting pin, ordered so will report. Bought a spring in the up to 20psi range s well, he as various springs as well as diaphragms.
Priced to please!
 
Just found a local AUS guy wth an interesting pin, ordered so will report. Bought a spring in the up to 20psi range s well, he as various springs as well as diaphragms.
Priced to please!

He doesn't have any shipping options for the US. Does anyone else in the states have interest in this? We could maybe do a group buy?
 
Has anyone ever considered stand-alone electronic boost control?

I have a G-turbo green wheel in my HDJ81, and I get what I understand to be high turbine pressure resulting in high EGT's at high rpms.

I was messing with tunes on my Subaru recently and noticed that the turbo map tapers off into the higher rpms. It's cutting boost because the turbo is getting out of it's efficiency zone.

This got me thinking, if I could taper the boost (and the fuel via boost compensator) at higher RPM's I could tune more aggressively in the mid range.

My current tune is set so I don't really have to watch EGT'S when I'm pulling the mountain passes (Colorado) but I know I'm leaving mid range performance on the table.

So the theory is, as the RPM's go above around 3k, the controller will start tapering boost which will taper fuel as long as I've got my boost comp spring and pin set-up just right.

The other direction I could go would be to modulate the pressure acting on the boost compensator electronically.
 
He doesn't have any shipping options for the US. Does anyone else in the states have interest in this? We could maybe do a group buy?
I own Tillix, I can ship to the USA using DHL or Aus Post express.
If you found a few people that want to buy them it would be alot more cost effective for me to ship them all in one hit, then use the US domestic postal system to get them where they need once they arrive there.
 
Has anyone ever considered stand-alone electronic boost control?

I have a G-turbo green wheel in my HDJ81, and I get what I understand to be high turbine pressure resulting in high EGT's at high rpms.

I was messing with tunes on my Subaru recently and noticed that the turbo map tapers off into the higher rpms. It's cutting boost because the turbo is getting out of it's efficiency zone.

This got me thinking, if I could taper the boost (and the fuel via boost compensator) at higher RPM's I could tune more aggressively in the mid range.

My current tune is set so I don't really have to watch EGT'S when I'm pulling the mountain passes (Colorado) but I know I'm leaving mid range performance on the table.

So the theory is, as the RPM's go above around 3k, the controller will start tapering boost which will taper fuel as long as I've got my boost comp spring and pin set-up just right.

The other direction I could go would be to modulate the pressure acting on the boost compensator electronically.

If you are in the usa you guys get really cheap unichips over there. You could very easily wire that up and have independent 3d boost mapping.
As well as a bleed-type setup attached to the Compensator for fuel control to tune separately from the boost curve.
Plus the million other things you could do with it if you wanted to.
 

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