Vacation fun

[dripley]

I dont think the ECM is capable adjusting for elevation, unless the map sensor can some how communicate the difference in atmospheric pressure at altitude. I would not know for sure.

[98whitelightnin]

I’ve been reading up in this and it seems a lot of people have the exact problem I had. I need to get timing tools and advance it a bit and also new injectors. Truck runs too darn good down here in the low country.

[Mopar1973Man]

On 7/4/2019 at 10:19 AM, JAG1 said:

So does that mean worn injectors are harder to detect on a VP truck since the ECM can compensate?

 

Pretty easy...

 

[Evan]

A 24v will compensate for altitude well not altitude but the lack of air. It will adjust the fuel air ratio timming everything really. The 12v wont, itl run richer with less air, less dense air at altitude. Itl always push the same timming and fuel unless you physically change it.

 

However the vp and all computer controlled trucks will make more power at sea level because the air is dense more of it. The fuel air mixture there will create more power it's like stuffing more air and fuel into the combustion chamber.

That's why most all hp ratings are done at sea level or very close to see level 

Edited July 10, 2019 by Evan

[Mopar1973Man]

On 7/9/2019 at 11:02 PM, Evan said:

A 24v will compensate for altitude well not altitude but the lack of air. It will adjust the fuel air ratio timming everything really.

 

No compensation. 

 

As you go up you foot goes down more fuel is added. There is no air / fuel ratio nothing to measure or monitor it. Timing is controlled by your foot once you pass 20% engine load the timing just retards deeply that all. The key factor is IAT below 80°F then timing advances. Above 80°F then it retards. I live in a area where I can go to 9,000 plus feet above sea level (Heavens Gate - Riggins, ID) and drop to as low as 800 above sea level (Lewiston, ID). 

 

Fueling is based on boost. As you climb in elevation the air gets thinner and the turbo has tough time making same amount of boost. Since the fueling is based off of boost this just limits the power you can create even in stock form. You can't have max fuel will little to no boost. Boost pressure is the key to releasing more fuel. 

 

Once you have a Quadzilla and able to monitor live data in flight then you start understand much more. So climbing I'm typically about 14° BTDC and well over 35% engine load which means more fuel. My cutoff is 20% engine load then there is a -3° of timing based on engine load as load increases the timing advances. Then on the flat it settles to about 22° BTDC and a mere 15 to 17% engine load at 65 MPH. I  climb 3 grades twice a day. Travel 1,000 miles a week.

 

On 7/9/2019 at 11:02 PM, Evan said:

Itl always push the same timming and fuel unless you physically change it.

 

Not true. Even stock has its limits and will not keep same timing all the time. Again even running Quadzilla in Level 0 you can monitor STOCK ECM fuel and timing and its VERY dynamic and changes constantly. Stock ECM can dip very low in timing and can rise up to extremely timing at high RPM's.

Edited July 12, 2019 by Mopar1973Man

[98whitelightnin]

I ordered a set of 5x.012 injectors and asked that they be set at 305bar. Hopefully this will get me a bit cleaner burn and add a little mpg too.

[98whitelightnin]

Almost forgot about this rig is saw out in Colorado. I couldn’t get very good pics but you get the jist of it. It was a second gen with a wild paint scheme, pretty tough looking rig.

 

Edited July 19, 2019 by 98whitelightnin

[Tractorman]

On ‎7‎/‎12‎/‎2019 at 6:40 AM, Mopar1973Man said:

Itl always push the same timming and fuel unless you physically change it.

 

@Mopar1973Man, I think @Evanis referring to the 12 valve engine here.

 

- John

[Evan]

Doesnt matter what I'm talking about.

[98whitelightnin]

I set the timing at 16.5* last week and have been checking get temps on a certain part of my commute and they are constantly 50-60 cooler. 

 

Got the PDD 5x.012 sac injectors @ 305 bar in yesterday and they really woke the truck up! It runs strong and really clean, unless you really get on it. I’m still running stock gsk and I can definitely feel the new throttle response. They lowered my idle about 50 rpm so I need to bump that up. 

Edited July 25, 2019 by 98whitelightnin