That's a LOT of room to turn it up in the top end!
The Official 1HD-T/FT Fuel Pump Mod Tuning Thread
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That's a LOT of room to turn it up in the top end!
Caught my attention that low EGT at WOT make it really smoky in the low ..?
It's about knowing what you have ( more / less skinny pedal through the power band / boost range ) and later you will deal with the star ( compensator spring )
It's about knowing what you have ( more / less skinny pedal through the power band / boost range ) and later you will deal with the star ( compensator spring )
i haven't pulled any trailers or driven any long hills to push the egts. 110km/hr in 25 degree C heat on flat ground 600 F is as high as it gets (sorry about mixing celsius and ferenheigt. i'm used to celcius but my gauge is ferenheight). it's got loads of power through the boost range and i'm happy with it. i don't need more power. i just don't like leaving soot on the guy behind me 
. i might just turn down the off boost fueling a bit and see what happens. if i don't like it ill turn it back up and learn to drive with a little less loud peddle
. i might just turn down the off boost fueling a bit and see what happens. if i don't like it ill turn it back up and learn to drive with a little less loud peddleIt seems crazy to me that you are hitting a max of 600f pre turbo, with ample power, even with an intercooler. That seems way to good to me true IMO. Im tuned relatively conservative, with a max of 1000f pre turbo at sea level, intercooled, with a 16g compressor wheel on stock ct26 turbine at 14psi. I can hit 600f in a playground zone. I would be cautious you are seeing accurate results if you are certain your temp probe is in F and installed pre turbo.
While I agree with @tweeek and others about the EGT being very low, without a comparison, perceived power is relative to the person making the judgment.
If your use to driving a 3.5ton 70 series non turbo 1HZzzzzzz, any intercooled turbo diesel might feel like it has ample power.
@franklin40 can you give us an idea of the power you are able to use compared to something else that is known?
If your use to driving a 3.5ton 70 series non turbo 1HZzzzzzz, any intercooled turbo diesel might feel like it has ample power.
@franklin40 can you give us an idea of the power you are able to use compared to something else that is known?
This is the safe place to start.
By taking some fuel out, you stand to lose
- cloud of smoke
- low end throttle response
- a few minutes of your time.
I agree with this totally. Same can be said for what a "cloud" vs "puff" of smoke is.
Any suggestions above are assuming your EGT reading is accurate. If it is, you have a lot of room to play.
Clouds of smoke and very low EGT don't add up. It may be worth testing your EGT readings.
I was thinking about this waiting for the red light to go green driving home this arvo.
Right on cue, a dead original looking HDJ80 driven by an old timer turned the corner beside me. As he accelerated up the hill from the lights, I noticed the exhaust haze.
Smoke haze was visible for maybe 5-6 seconds as he went from walking speed at the corner, up to traffic speed (40-50km/h) up a moderate hill. Smoke dissipated by the time he'd gone 50-60metres
To me that was normal, to a Prius owner, it was evidence of an impending zombie apocalypse!
Hahaha. I agree.To me that was normal, to a Prius owner, it was evidence of an impending zombie apocalypse!
Add night time and the headlights of the vehicle behind and the apocalypse is here now!
OK, that's not a "max EGT" reading, that's a highway cruising EGT reading. Totally different things.
I had my truck in the mountains last summer, and with my current tune it was easy to keep the EGT's below 1250F up mountain passes with my right foot, but it would exceed that if you stayed in it and weren't watching. Now that I'm back home on the prairies, I can't get it to 1050F without staying into the pedal trying to see what my top speed might be. Cruising at 110km/h at about 16psi lands me around 850F if memory serves me, stock turbo, no intercooler.
600F at 110km/h on the prairies with an intercooler is reasonable I think. Sustained climbs heat soak the system, I'm talking several minutes at a time pulling up a grade, that's when you'll find out what your "Max EGT" really is. Impossible to tune for that without paying for dyno time or hooking on a trailer when you live in the prairies.
exactly. i think i'm in a good safe range right now. i'm going to tow a trailer this weekend which will push the egt higher for sure. my reason for posting that egt was to say that at boost i'm not over fueling. only off boost i have a little more unburnt fuel than i want.
yes installed the egt probe myself so can confirm its pre turbo. it's also a very good quality gauge and probe i have so i do believe it. ill report back after the weekend when i've pulled a trailer and maybe tweek the off boost a little.
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Are you seeing 15psi (that's your max, correct?) when doing 110km/h on the highway?
i found a hill and pushed it hard tonight. i was doing 120 up a hill with foot to floor into a headwind (and was still accelerating) and got to 800f. i was at about 12-13 psi of boost. it was set to 15 max and i've hit 15 once. it's only had the tune done for a week so i'm still getting used to it. 110 km on flat ground i'm at about 8 psi boost if i remember correctly
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That is still a rather conservative tune I would say. If your happy with the way its driving on boost, try turning down the no boost fuel with the smoke screw and enjoy.
Now the devil in me comes out and says there is potential for it to be better!
Given the info you have provided I would say you are not getting to your max boost of 15psi as there is not enough fuel being burnt to provide the turbo with the drive energy needed to produce that boost. As you are aware this is indicated by the low (comparatively) EGT readings.
More full boost fuel should deliver more boost (and more torque/power) but you will be tuning again from the very start.
Boost and EGTs at cruising conditions are somewhat useless, as there is just to many variables, and cruise is not at WOT.
You'll see peak boost and peak EGTs at WOT under load.
One way to do this is approach your hill of choice in 4th gear or Drive, try and hit the bottom of the hill at around 1500 rpm or less, once you've hit the incline, plant your foot to the floorboards and keep it at WOT for as long as you can, or up to your preferred max rpm.
As Ian said, you won't see a true max EGT until you have a sustained WOT run under load
You'll see peak boost and peak EGTs at WOT under load.
One way to do this is approach your hill of choice in 4th gear or Drive, try and hit the bottom of the hill at around 1500 rpm or less, once you've hit the incline, plant your foot to the floorboards and keep it at WOT for as long as you can, or up to your preferred max rpm.
As Ian said, you won't see a true max EGT until you have a sustained WOT run under load
If you're not hitting 15psi, either the wastegate is set a bit low, or you don't have enough fuel to generate full boost. EGTs suggest this is a possibility
diby 2000. that devil in you is playing with the devil in me!! i wanted a quick fix for my smoke but now i might have to screw around with it more!!
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k so as i said earlier i'm new to diesel tuning. i'm sure my waste gate is set to 15 so i'm likely not getting full boost as my fueling likely isn't enough at full boost. if i turn up the over all fuel screw this will push more fuel through and increase the boost correct? does that mean i need to rotate my boost compensator clockwise to increase spring tension to accommodate for that boost coming on earlier. my aneroid pin is turned to max right now. am i thinking about this right and is that the correct order of things to do?
Couple questions just to get the basics covered:
-how do you know the wastegate is set to 15psi? What are you using to adjust the boost level? I only ask as you've said you aren't hitting 15psi at full throttle.
-have you checked to ensure your getting full travel of the aneroid pin without getting into fuel cut at a 15psi boost level?
If you increase fuelling via the main fuel screw, you'll increase fuel across the board, making your smoke off-idle issue worse, hence the need to retune everything from scratch.
right. so here we go with some real world numbers. i pulled a 4500 pound trailer into a very stiff prairie wind up a hill. max boost with foot to floor was 16 psi and i hit 1250 f for a few seconds. i drove for about 20 minutes into wind and up as many hills as i could. some mild/moderate inclined for 5 km or so and averaged 1150f. i think my tune is pretty good and i dont want to mess with this after all so all my questioning has proven moot! sorry everyone but it's a good way for me to learn. is 1150-1200 sustained temp ok? i'm just going to get used to the smoke and not push the gas pedal so hard when shifting if i don't want to smoke too much
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