The Official 1HD-T/FT Fuel Pump Mod Tuning Thread (3 Viewers)

[AnalogMS]

If you can hit the bottom of a hill coasting, stand on the gas so you are under full load from 2000rpm-ish and hold it until you hit around 3600 to 3800rpm-ish, this should give an indication of peak EGTs.
A steeper hill is better, but you gotta work with what you got.

650⁰C is well below a safe max EGT. 750⁰C is widely considered safe.

I tuned mine for a max EGT around 850-900⁰C.
Reality is, you'll never hit that with normal driving. It's only when you're pulling a step Mountain pass, or towing a heavy load up hills that you need to be careful of exceeding this.

It's normal for the hdj80s to emit a bit of a smoke haze/puff as you accelerate or give it a bit of gas to pass, or give it more gas for a hill.
I used to notice this haze at night with a car behind me. The headlights will show it up.
That's about the only time I'd notice it, unless i had really buried my right foot in the floor

Thanks. i did some research after the trip and realized i think i was being a little too careful on the EGT's. i'm also running a Gturbo green wheel with no FMIC on the stock crossover pipe, so its basically just pumping hot air.

PDI front mount is arriving next week so that should help alot. going to have to dive deeper into the fuel pump tuning as i plan to up the boost to around 20.

 

[AnalogMS]

Ok, diving head first into this, since i got my intercooler installed and boost turned up to around 18PSI. a few things hopefully someone can give me input on:

- the aneroid diaphragm hits the intake runner when pulling straight out, so i have to remove the diaphragm from the aneroid to get it out, in all the videos i've seen, i've never seen this or heard it mentioned. makes it a real pain to mark the diaphragm since it has to be re assembled everytime, so instead i've had to mark the actual aneroid rod head. (not a huge deal)

- i had two shims of the same size in there, looking at the aneroid, it was obvious where it had ridden for its entire life, on the lowest profile (least fuel). stopping just short of fuel cut. i ground down the entry to get it back on and sharpied the profile. all good.

- what should my process be here for getting the tune set straight? start with the star wheel and work my way out? as of now it drives good and EGT's are good. i think there is room for improvement though. my main gripe is i seem to be really rich in the coming into boost range, or if i for example give it a hard rev at idle, it just plumes black smoke. i'd like to clean this area up.

 

[KiwiDingo]

- the aneroid diaphragm hits the intake runner when pulling straight out, so i have to remove the diaphragm from the aneroid to get it out

You must be running very advanced in your timing for that to occur. Could also be a cause for some of the black smoke you mention as that can also happen under certain situations with too much timing.

 

[AnalogMS]

You must be running very advanced in your timing for that to occur. Could also be a cause for some of the black smoke you mention as that can also happen under certain situations with too much timing.

i haven't dove into timing yet, but from what you're saying, the position of the pump determines the advancement or retard of the timing?

 

[KiwiDingo]

For the static timing, yes. When you loosen the pump to set static timing you either rotate the pump towards the engine for more advance or away from the engine for less

 

[AnalogMS]

For the static timing, yes. When you loosen the pump to set static timing you either rotate the pump towards the engine for more advance or away from the engine for less

its possible. i will have to add a timing check to my list of things to do. i have really no reason to believe timing is off, it runs pretty strong, and doesn't smoke at at idle, just coming into boost, and its mostly black.

 

[AnalogMS]

Ok, i think i got the aneroid travel dialed in.

in my opinion and adventures into this, it seems like the best first step if you've increased boost pressure (20 PSI for me) . luckily we have a handy pressure calibrator at work i was able to use, otherwise im sure the bike pump trick works fine.

first test to 20 PSI. pretty deep into the fuel cut

after roughly 2 1/2 -3 counter clockwise turns on the star wheel, and the stop screw set to max travel (and only one shim not two like it had from factory)

set the aneroid clocking to the midway point between low and max on the counter clockwise side from lowest.

very light puffs of black smoke under full throttle briefly, drives good. need to have someone follow me or set up a camera in the rear, for me this is the hardest part is monitoring smoke, also living somewhere that's flat with no hills. EGT's stabilize around 500C which seems low, but when i rotated the aneroid more towards max fueling it was puffing black way more. want more fuel and power but don't want the smoke.

that's where i'm at now, i still think i can dial in more fuel at off-boost and a little up top. also sorry for blowing up this thread recently, just figured i would share my experience for future readers.