tuning? good input wanted no bashing!!

[redws6rocket]

What are some of the specs on what you are tuning? Mainly injector size, camshaft rpm range, and turbo size....

old set of troys injector tips, not sure how big they are? they are pretty big, steve's biggest cam, x2 cp3's, a big precision charger, it is a huge 3.4 charger with a 2.6 cover. i just want to get the the up top part of the tune better, and it is very hard to light, i am struggling with it down low some too, i can only get it to about 1900 rpm in 4lo and it just stops fueling, you can move the pedal all the way to the floor and nothing? got any ideas?

 

[JoshH]

Pulse width is depends upon what size injector you are running and what horsepower you are trying to achieve. My personal opinion, for what it's worth, is you should run an injector big enough to reach your horsepower goal and not go over 2500 uS (especially if you are running lots of RPM).

As far as timing, GeneralTJI did a pretty good job of answering that one. Depending on the RPM and pulse width, I wouldn't be too worried about 29 degrees of timing.

For the not fueling past 1900 RPM, do you have the tune setup to limit fuel for a given MAF reading? It could be cutting fuel because it isn't seeing enough air to give it more fuel and since it doesn't have fuel the turbo won't spool and draw in more air. Kind of a vicious cycle that chases its own tail. Not sure if that is your problem, but maybe something to look at.

 

[bullfrogjohnson]

Thats big of a charger bushed to a 2.6 is gonna be hard to light. What size turbine wheel and housing?

What do your EGT's look like on the line spooling? My truck has responded very well to very low timing on the line with a fair amount of fuel. I bring it up nice and slow and get at least 1000* EGT and it will light everytime. Make sure you are keeping you fuel pressure up. With BIG injectors there is a huge pressure drop as soon as the injector opens. If the pressure is not ramped up you will get big fuel droplets and smoke and your egts will get to around 750-800 and sit there. It is just putting the fire out.

 

[sweetdiesel]

Thats big of a charger bushed to a 2.6 is gonna be hard to light. What size turbine wheel and housing?

What do your EGT's look like on the line spooling? My truck has responded very well to very low timing on the line with a fair amount of fuel. I bring it up nice and slow and get at least 1000* EGT and it will light everytime. Make sure you are keeping you fuel pressure up. With BIG injectors there is a huge pressure drop as soon as the injector opens. If the pressure is not ramped up you will get big fuel droplets and smoke and your egts will get to around 750-800 and sit there. It is just putting the fire out.

Good info! Also Josh h posted some great stuff
I remember now that you asked for help on spooling big chargers and we gave you some info but asked for a log to further help.... You neverdid post a log or give any results???? So good luck! It gets old helping people that never return
feedback

 

[IOWA LLY]

old set of troys injector tips, not sure how big they are? they are pretty big, steve's biggest cam, x2 cp3's, a big precision charger, it is a huge 3.4 charger with a 2.6 cover. i just want to get the the up top part of the tune better, and it is very hard to light, i am struggling with it down low some too, i can only get it to about 1900 rpm in 4lo and it just stops fueling, you can move the pedal all the way to the floor and nothing? got any ideas?

Try looking at your torque tables, (B0741, B1102) and max fuel vs airflow tables (B0751, B0752) for the cause of no fuel past 1900. It will be one of those I almost guarantee it.


I would start at 2200us and work up from there. As far as timing, that depends on how high you plan on spinning the motor, and what you are running for pistons. I would stay to the lower side of things if your still running cast pistons.

 

[MACKIN]

Just wondering

When it comes to logging a tune with a Tech II what about when you run a plug and play like a Edge box that intercepts the signal?

Splain that for me Benny

 

[redws6rocket]

Good info! Also Josh h posted some great stuff
I remember now that you asked for help on spooling big chargers and we gave you some info but asked for a log to further help.... You neverdid post a log or give any results???? So good luck! It gets old helping people that never return
feedback

i just don't have any good logs, i have been working with my buddy on driving. he does a good job of setting there and slowling raising rpm, but then gets excited and swats the throttle. he then backs off the throttle, the truck rolls out about 50 ft and then lights. i will post the last log i have, and i thank you guys for all the help! learning alot of new stuff!!!

 

[duratothemax]

Just wondering

When it comes to logging a tune with a Tech II what about when you run a plug and play like a Edge box that intercepts the signal?

Splain that for me Benny

OK FINE...theres an example of when data from the tech 2 doesnt reflect what the engine is actually doing. :

 

[MACKIN]

OK FINE...theres an example of when data from the tech 2 doesnt reflect what the engine is actually doing. :

Just had to do it, I already knew the answer. :angel:

 

[Rhall]

i just don't have any good logs, i have been working with my buddy on driving. he does a good job of setting there and slowling raising rpm, but then gets excited and swats the throttle. he then backs off the throttle, the truck rolls out about 50 ft and then lights. i will post the last log i have, and i thank you guys for all the help! learning alot of new stuff!!!

Ask him if he wants me to drive :coal: :rofl: JK JK

 

[redws6rocket]

Ask him if he wants me to drive :coal: :rofl: JK JK

we tried third gear but his truck did not like it! i will tell him that :hug:

 

[redws6rocket]

Try looking at your torque tables, (B0741, B1102) and max fuel vs airflow tables (B0751, B0752) for the cause of no fuel past 1900. It will be one of those I almost guarantee it.


I would start at 2200us and work up from there. As far as timing, that depends on how high you plan on spinning the motor, and what you are running for pistons. I would stay to the lower side of things if your still running cast pistons.

can i just max out B0751 and B0752?

 

[IOWA LLY]

can i just max out B0751 and B0752?

Yes.

 

[sweetdiesel]

Yes.

So if I adjust that table will I gain fuel?

Honestly do you really know what your talking about?

 

[JoshH]

So if I adjust that table will I gain fuel?

If your fuel is being limited by the MAF sensor, you should.

 

[redws6rocket]

If your fuel is being limited by the MAF sensor, you should.

another question, how do i set up my maf flow rate scale? i take this is very important since i do not pull much air across the sensor at idle, but max out the sensor up top!

 

[JoshH]

another question, how do i set up my maf flow rate scale? i take this is very important since i do not pull much air across the sensor at idle, but max out the sensor up top!

I think it was Johnboy who posted a pretty good method for calibrating the MAF scaling table somewhere. It involved attaching the stock intake tube, with the MAF sensor installed in it, to the new intake tube and logging MAF value and voltages while incrementally raising RPM with the DVT function of the scan tool. Then disconnect the stock intake tube and reinstall the MAF sensor into the new intake. Raise the RPM to the same increments you did in the first test. Make note of the MAF voltage at that RPM. Now go into your tune to the MAF scaling table and enter the MAF value at the voltage of the new tube for the same RPM. Hopefully that makes sense.

 

[sweetdiesel]

If your fuel is being limited by the MAF sensor, you should.

never seen that table affect fuel....it has very little effect on anything jmho

 

[sweetdiesel]

another question, how do i set up my maf flow rate scale? i take this is very important since i do not pull much air across the sensor at idle, but max out the sensor up top!

what rpm is the truck running?

wot up to 3200 is allready maxed

 

[JoshH]

never seen that table affect fuel....it has very little effect on anything jmho

In most cases it doesn't, but it can. That is why if you max out all the values the truck will blow more smoke before the turbo spools up. Here are a couple of screen shots from the same tune with only tables B0751 and B0752 modified. Notice the first one (the one with stock tables) has more air flow but less fuel quantity than the one with the tables modified.