I'm guessing your pin is probably rotated to the least aggressive side. If you are happy with your power, leave it and enjoy cool EGTs!
The Official 1HD-T/FT Fuel Pump Mod Tuning Thread
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I'm guessing your pin is probably rotated to the least aggressive side. If you are happy with your power, leave it and enjoy cool EGTs!
I hadn't heard any updates on this spacer so I just ordered one from your website and i'm going to test it all out myself and see how it goes. Pulled mine apart over the weekend and it looks as though it should work so keen to see.
I ended up with a TORFAB fuel pin. I also ended up getting another exhaust made. I now have a true 3.5in dump pipe and 3.5in stainless exhaust.
The TORFAB pin forced me to take nearly 1/2 a full turn out of the main fuel screw. My AFR was exceptionally low at 14:1 on spool up and 19:1 at full boost 21PSI. Overall I really like the response that the pin has given me down low. I had to tighten up spring tension quite a bit but once I tuned for the new pin im sitting around 16:1 down low for spool up and 22:1 up top.
I find myself scratching my head though about these AFRs. It seems most people get their panties in a bunch when seeing pre-turbo EGT at 1250F. With my AFR being 22:1 I rocket past 1250F in 4th at around 3000-3200rpm at 21PSI Green Wheel. I truly don't know where my EGT will stabilize because I'm worried about going much past 1400 which I have seen so far all before 3500RPM. Some very reputable folks in the industry have said 1600F pre turbo is safe on a brief pull.
Either 1600F is safe for a quick pull or my truck would blow up on a dyno run in 4th with this AFR.
what is the function of this?
Increased range of the timing piston which is needed with increased fueling and high RPM
No surprise about your EGT skyrocketing above 3000rpm with that teenie tiny hotside on that turbo you're running. I'll see your can of worms and raise you another
hahahaOut of all the setups and turbos I've tried absolutely nothing came close to the crazy high EGT I would experience than with what I had with that incredibly small hotside on the grunter I ran. I even had to run it at 24:1 AFR to try and keep temps under control but it still would get to over 900 degree C pre-turbo near instantly. No thanks, my tiny turbo hotside days are over.
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I suspected this. Another reason to go bigger.No surprise about your EGT skyrocketing above 3000rpm with that teenie tiny hotside on that turbo you're running. I'll see your can of worms and raise you another
Out of all the setups and turbos I've tried absolutely nothing came close to the crazy high EGT I would experience than with what I had with that incredibly small hotside on the grunter I ran. I even had to run it at 24:1 AFR to try and keep temps under control but it still would get to over 900 degree C pre-turbo near instantly. No thanks, my tiny turbo hotside days are over.
Thanks for the order!
Looking at the internals of your pump it looks like it should fit!
Being a Land Rover and Cummins nutter means when it comes to trying to fit Toyota Denso or Isuzu/Diahatsu Zexel pumps I struggle with what model numbers to eBay search for to get pumps for product development.
I have a Diahatsu Zexel here ready for Boost Pin development when lock down is over and I can visit the machine shop again.
Keep me in the loop when the spacer kit lands with you I would be very interested to see results!
I experience similar afr to egt relationship now also.
I had a good run up a nice incline yesterday.
Running Gturbo bad-boy (red wheel?) at sustained 32psi, 2200rpm, intercooled with a 3 inch exhaust, built pump and +30 injectors, about 22c ambient temp.
Afr was at 24-25:1 and egt eventually steadied at 750c pre by the top of the hill.
I'm happy with performance, maintained 100kph the whole way up the hill on cruise control.
I had a good run up a nice incline yesterday.
Running Gturbo bad-boy (red wheel?) at sustained 32psi, 2200rpm, intercooled with a 3 inch exhaust, built pump and +30 injectors, about 22c ambient temp.
Afr was at 24-25:1 and egt eventually steadied at 750c pre by the top of the hill.
I'm happy with performance, maintained 100kph the whole way up the hill on cruise control.
Has anyone seen what type of plate they have on the other side of their timing advance piston? I see there are two types, one's flat and the other has a step shifting the piston about 4mm advanced from what the flat plate would achieve. The plate with the step in it seems less than ideal as it reduces the overall travel of the piston, @NRS91 have you seen these two types before? I've been told that 1HD-FT pumps normally come with this step plate so maybe removing this for the flat one will also help me get more travel from mine.
Very interesting!
I tend to only tinker with the Bosch varient which have the flat plate.
Though they use different size pistons in different applications so maybe the interchangeable plate and adjustable timing advance top hat plate are a more affordable way to achieve the different calibrations?
I kind of skipped over and started on Page 40. 
.
But, in case it wasnt discussed, the manual says to drop in 1.5 - 2.5 cm^3 (0.09 - 0.15 in^3) in the bushing hole.
See pic:
Also, for anyone perusing the threads like I have been, side profile of the diaphragm:
That being said, I finally had the courage to install the custom machined Aneroid Pin that I gor from @torfab about a year ago.
This was in part due to buying an intercooler(PDI FMIC) Turbo upgrade(GTurbo BBX, Red Wheel) amongst other things.
Anyway, back to the aneroid pin.
When you install a custom aneroid pin, make sure to rotate it 180 degrees. Otherwise the truck will not essentially get proper fuel.
Also, add a little bit of engine oil per the manual. DO NOT put WD40 like my "friend" did. It does not help.
I also used a couple of Cotton swaps to clean out the rust as much as I can.
.But, in case it wasnt discussed, the manual says to drop in 1.5 - 2.5 cm^3 (0.09 - 0.15 in^3) in the bushing hole.
See pic:
Also, for anyone perusing the threads like I have been, side profile of the diaphragm:
That being said, I finally had the courage to install the custom machined Aneroid Pin that I gor from @torfab about a year ago.
This was in part due to buying an intercooler(PDI FMIC) Turbo upgrade(GTurbo BBX, Red Wheel) amongst other things.
Anyway, back to the aneroid pin.
When you install a custom aneroid pin, make sure to rotate it 180 degrees. Otherwise the truck will not essentially get proper fuel.
Also, add a little bit of engine oil per the manual. DO NOT put WD40 like my "friend" did. It does not help.
I also used a couple of Cotton swaps to clean out the rust as much as I can.
Spacer kit has arrived, hopefully fit it during the week. Spacer plate is about 4mm and the spacer washer for the springs is just over 2mm. Should the washer not be the same thickness as the plate to keep the same preload on the advance piston as before? Just curious, I have adjustability in my preload so I can always add the extra 2mm with my adjuster screw if need be.
On the Bosch pumps the timing advance spring becomes coil bound if you have a larger shim, which limits travel and isnt ideal for the spring.
The CNC machined shim in the kit is the most pre-load while still getting full travel but it will advance a little quicker with the revs.
Thanks @NRS91 , I just figured I'm currently able to get full piston travel with my current level of preload on the spring without binding as I can see evidence of where the piston is hitting the end cap at full advance position. I was going to set it up the same thinking that there's still enough case pressure to continue to move the piston further than where it is currently limited by the end cap with your spacer installed giving me more timing in this higher rpm zone. In any case I'll trial a few different preloads and see how it performs and also see if in fact I can fit that shim of yours in behind the springs against the timing piston.
Bare in mind that you're adding 4mm to the overall travel so you are more than likely going to hit coil bind if you shim 4mm too, but if you compress the spring in a vice you can measure static height, installed height and coil bound height and compare to adjust to suit these pumps.
Case pressure sweeps from 60-80bar to 160bar roughly on a VE pump, would be interesting to compare.
Had some time this arvo to install the spacer and check it all out. The shim in the kit can't be used behind the spring as it doesn't fit over the bump on the servo inside the timing piston that I have in my FT pump but I think if I drill it out I can fit it in the end cap. Which leads me to my next interesting find, the adjuster on the end cap only works on the inside spring as the outside spring doesn't sit on the piece that moves with the adjuster. The outside spring had one shim already in there to adjust the preload on it, I wonder why the adjuster on the end cap only works on the inside spring even though both springs are pushing against the servo in the timing piston.
Ah ok its similar to the Euro 1 300TDi and Cummins 6BT with the twin springs, i believe it allows better control over the timing advance.
Drill the shim out and install in the cap then test would be my advice.
If you turn the engine over with a breaker bar the timing piston should move out, would be interesting to see its full travel to compare with Bosch.
Would there be any interest in a bespoke Boost pin for the jap pump? Made to the same material spec as a stock pin.