Tuning school

[CurtisF]

Some one correct me but if you lower icp and keep pulse width the same you get less fuel thus it should have at min changed the idle rpm.

If it did, it was barely noticeable. I could faintly detect a change in idle "tone". So there was a difference, just nothing drastic.

Any larger swings in ICP resulted in a hint of a chop creeping on me, which is what the truck was doing just a little bit from time to time before. Lowering the PW got rid of that issue, but mysteriously presented hazing.

I think adding 2 degrees of timing in your idle area is worth a shot that should help make for a cleaner combustion.

And I'll probably try that, along with any other suggestions that folks have. Just to note, timing was completely untouched when I made the other changes, and it wasn't hazing before.

I know on a lly duramax with larger injectors i tuned this weekend I had to raise the fuel pressure at idle to clear up a light haze. Which is like raising icp so yeah getting a haze when adding icp doesn't seem normal.

Are you data logging?

I didn't record, I was just watching on AE.

 

[CurtisF]

wait... why is the injection delay table set to 1 in the region it is idling right now?

I've had it there for a while and never really messed with it. Kinda forgot about it until I posted the map up in this thread. At one point I think it was at 1.5 or 1.6 in the idle range, but that was a long time ago.

You think that's where my problem is? If I bump it back up, that will give me another what.. 2 degrees of advance?

 

[CurtisF]

Chips will be in the mail tomorrow!!!

Thanks buddy!

Wait till next week. I'm leaving town early Wednesday morning and won't be back until the following Wednesday. Don't want the box sitting on my front porch that whole time, especially if it snows while I'm gone.

 

[Gearhead]

That delay is pretty close to the stock value up to 112 degrees C actually. The column to the left starts adding timing back in because it is being pulled elsewhere in the calibration. I would just add some more timing at idle maybe 3 degrees and see if you notice a change. I guess it depends on the VOP of your hybrids, but most have trouble making uniform fuel below 500 PSI. The 200% nozzle is just a bit large to have perfect manners..... we need to do away with the 100% and have like a 130% or something like that but get there with minimum extrude hone work like the 80% I love so much.

 

[CurtisF]

That delay is pretty close to the stock value up to 112 degrees C actually. The column to the left starts adding timing back in because it is being pulled elsewhere in the calibration. I would just add some more timing at idle maybe 3 degrees and see if you notice a change. I guess it depends on the VOP of your hybrids, but most have trouble making uniform fuel below 500 PSI. The 200% nozzle is just a bit large to have perfect manners..... we need to do away with the 100% and have like a 130% or something like that but get there with minimum extrude hone work like the 80% I love so much.

Yeah I know it won't be absolutely perfect, but it's damn near close right now except for the slight haze. I'll try the timing and maybe raise the ICP to go with it and see what happens. Maybe the combination of both will work together. I'll try one at a time, with timing first before ICP, to see the results.

Thanks for your input, I'll let you know how it works. Also if you see anything else quirky in those tables, let me know. It's been a while since anyone has critiqued my tunes.

 

[Gearhead]

The first 2 columns on the right are 700 and 1000 rpms for the timing tables. I thought the altitude and full boost table used the same x axis but maybe I'm wrong on that.

 

[CurtisF]

Ok, so update....

I made the changes to ICP and timing. Drove it to NOT and parked it back in my driveway. With ICP at idle bumped up to a little over 500 psi, and added 3 degrees to timing at idle, the haze was cut down. There was still a trace of it, but I could switch back to the old tune and the other tunes with just ICP and timing only changes and see (and smell) a difference. The idle in the updated tune with both ICP and timing changes remained smooth and didn't chop. So it looks like it's getting closer. A few more tweaks and I should have it all set where I want it.

I'm also going to address some timing changes regarding cold start idle as well. I think there's some mop-up work there to help cut down on the white smoke when it's below freezing.

Thanks for the help guys, I really appreciate it! Definitely helps to have some experts weigh in on a novice like me. :grouphug:

 

[Power Hungry]

There are a few things going on here that contribute to the haze.

First off, there is the combination of 250cc hybrid injectors combined with 200% nozzles. Hybrids have a lower Intensifier Piston multiplier and therefore produces a lower injection pressure at the nozzle. In an ideal world, you'd simply raise the ICP, lower the pulsewidth, and everything would be cool. However, the HEUI injection system has some severe limitations.

HEUI injectors become extremely unstable when the pulsewidth falls below 1.0-1.2 ms. An ideal idle pulsewidth would be 1.8 - 2.2 ms, but with 200% nozzles, this simply is not feasible, usually resulting in pulsewidths in the 1.3 - 1.5 ms range. The higher you raise the ICP (in an attempt to alleviate the hazing), the lower the pulsewidth is going to be forced in order to maintain idle. Once pulsewidth falls below 1.2 ms, the idle starts to get choppy and/or starts rolling. In order to stabilize the pulsewidth, we often reduce the ICP but that also can cause a rolling idle, not to mention that the drop in ICP reduces injection pressure and results in poor fuel atomization... ie. Hazing.

There are going to be some concessions you're going to have to make to have a smooth, stable idle. A slight haze is often the cost. However, one thing I did notice is that your Injection Delay is extremely low at idle. I's strongly recommend raising it to about 1.5 - 1.6 ms (thereby advancing the SOI) and that will help to dramatically reduce the hazing by allowing the the fuel more time to burn in the cylinder. Obviously, you'll want to quickly ramp down the delay by the time you hit 8 MPa so you're not pushing the SOI under load.

Give that a shot and let me know how it comes out.

 

[2000wa250]

From recollection my tunes at idle are running about 1.5 Ms pw. No haze. Pretty much stock tuning with 250/200% injectors. However it does roll a little bit when up to temp. Looking at yours id bring icp up a bit. It may be a louder idle but in my experience it will be smoother.

Sent from my DROID BIONIC using Tapatalk 2

 

[JD3020]

Finally got Minotaur and up running, lets get this thread going again!

 

[rusty1161]

Sweet!

Rusty

 

[Dieselboy.]

I've found that lower icp is smoother on big hybrids.
But mine does have a slight roll to it.

My icp is at 425ish at idle with 1.5-1.6ms of pw. Idle speed set to 715. I started just throwing more timing into it and with an extra 7* of timing it cleaned up a bit and was still smooth and not choppy like added icp seems to make it. I've found that with 550+icp idle quality just goes down the tube.

I'm curious to try 400% nozzles now.

 

[vanderchevy18]

I keep thinking that I want to do my own tuning. The problem though is that running my own shop, I want to give the best possible product I can. And to me that means leaving the tuning up to the pros. I generally push the php hydra and matts tuning for upgraded injectors. No mailing. No waiting. No burner. Email the tunes and hook up to the chip from your laptop. Just like sct but easier and faster. I was at the track one night. Made a pass, stuck a new tune on, made a pass, told matt what it was doing, he sent me a new tune, made another pass, emailed a new tune, made another pass, etc. It was amazing. I loved every second of it. Now, that being said, I'm definitely following because I want to learn more about it. Thanks guys for sharing!!

 

[JD3020]

I keep thinking that I want to do my own tuning. The problem though is that running my own shop, I want to give the best possible product I can. And to me that means leaving the tuning up to the pros. I generally push the php hydra and matts tuning for upgraded injectors. No mailing. No waiting. No burner. Email the tunes and hook up to the chip from your laptop. Just like sct but easier and faster. I was at the track one night. Made a pass, stuck a new tune on, made a pass, told matt what it was doing, he sent me a new tune, made another pass, emailed a new tune, made another pass, etc. It was amazing. I loved every second of it. Now, that being said, I'm definitely following because I want to learn more about it. Thanks guys for sharing!!

I'm wanting to do something like that. With the new stuff i've now got 2 chips and a burner, 1 chip is my current one with Gearhead tunes, and the 2nd is blank for my own tunes. Current plan is to sell it all, and get a Hydra. Then, if possible, have Matt e-mail me tunes to put on it, plus i can just hook the laptop up and throw my own tunes on it. So i'll never have a waste a second dicking around with pulling the damn chip out and burning it, or swapping chips. Simply hook the laptop up to the Hydra, upload some tunes, and move on. Actually going to talk to PHP and Matt about that this week.


And i'll be throwing a ton of questions out this week hopefully. Spent just a wee bit of time going through it, and the more i'd look at something the more lost i became. LOL

 

[JD3020]

I now have a question, working on a sledpull tune, which i'm wanting full fuel up past 4k RPM's, and hopefully shift points up around 3500-4k. Is it possible to turn off all the adders and multipliers so the truck is only running off the basic maps, and will do what i command it to, and not have to worry about another table changing something? Just an idea in my head right now.

 

[Dieselboy.]

From what I understand you are asking, All you would have to do is extend the fuel vs RPM table to 4000rpm or whatever RPM you choose to run it out to. That basically controls your rev limiter. So I would fuel 100% till 4000rpm and then set 4150rpm to 0% so you still have a rev limiter in place.
The rest of the tables would just use your max value and continue it to 4000rpm. So You would probably need to watch SOI as it would change as it climbed in RPM.

 

[JD3020]

Ok, that sorta makes sense.

Now a question about that table, what exactly does that % mean, or relate to?

And for those who like picutres(like me), this is the table.

 

[POWER-STRUCK]

looks like fuel limit table based on oil temp/rpm

 

[JD3020]

looks like fuel limit table based on oil temp/rpm

Correct, and this is a stock file for a TDE1(97 auto) truck. I sorta have an understanding of what the MFD table is, and how it works, just not sure what the % values in the fuel limit table mean. What exactly is it limiting? And what would happen if i set it all to 100%

And another newb question, how can i adjust the scaling of the table, such as the Fuel limit vs. RPM table, to go to my desired RPM range? Like how it stops at 3700 now, how do i get it to go up to say 4500?

 

[POWER-STRUCK]

this may be a question best answered on the php forums, I'm not sure if you can make adjustments to the template. try pressing ctrl/alt/enter and see