Timing question for high altitude

[blacksmoke94]

With a half turn on the IP and all of the driving being done at an average altitude of 4500/5000ft, should the timing be advanced a little to compensate for the lower available oxygen and increased fuel? Is there a formula or a known degree of timing to figure out what's best for different altitudes? This has been bugging me since I moved here and I think it's time to finally do something about it. Any pump guru input is greatly appreciated. Thanks in advance.

 

[icanfixall]

I'm no pump guru but I know a little about timing. I suggest running 9.0 to 9.5 advance done by the plus timing method. Not the lumi type timing method. Do you have a meter... This can't be done by ear either. No shop on this planet can accurately time our engines by ear.

 

[blacksmoke94]

What is the difference between "plus" and "lumi"?

 

[chris142]

one measures the fire in the hole and the other style senses the pulse in the injector line

 

[icanfixall]

The lumi method of timing is placing a luminosity probe in number one glow plug hole. then when the enfine fires on that cylinder its recorded in retarded timing degrees. Its been worked out before and the line clamp method called pulse timing ia the same degrees as the retarded lumi method. Its well known that the application of a line clamp is so much easier than removing a glow plug. All you need to do is sand the injector line clean to bare metal for the best contact area. When your done place some electrical tape on the line so it wont rust. Next timing event your ready to go. This tip comes from Mel.. The Moose Pump and timing guru..

 

[blacksmoke94]

That's great info and thanks. I watched a video on the pulse timing method and it looks and sounds a lot easier than messing with a glow plug. I know it needs to be advanced a little with the combo of the higher altitude and increased fuel. It's a little sluggish from a start and when it shifts gears, there's a little lag there and if I'm not ******* the throttle, she can smoke pretty good until the rpm's get up a bit. It's like the "power band" or whatever you want to call it really doesn't kick in until 2200 rpm or so. It might help the fuel mileage a little too without having all the unburnt fuel goin out the pipe. I'm hoping. haha

 

[icanfixall]

What you can do without a timing meter is advance it but first make a punch mark with a center punch right in the joining line between the pump body flange and the gear cover flange. Then when you move the pump the mark becomes 2 half circles. If you don't like how it sounds or runs its really easy to move it back. All you do is make the 2 half circles make a full circle again. Might try moving 1/8 inch. Moving the top of the pump towards the passenger fender is advancing the timing.

 

[79jasper]

I can't remember for sure, but I think Mel said something about the fuel screw affecting timing.

Sent from my SM-G900R4 using Tapatalk

 

[Black dawg]

I remember reading in an old diesel truck manual (looooong time ago) that the actual ignition event is slightly advanced as elevation goes up. Meaning that higher elevation would need less static timing. I dont know if this is true, but my trucks always seem to rattle harder at higher elevation. My trucks get used between 3k and probably 9k elevations.

I have tried the 9.5 deg as suggested by this site, and is always too smokey and too much rattle for me. I usually end up in the 5.5-7.5deg range depending on fuel rate. I have not seen poor mpg from these "slow" timing settings.

 

[blacksmoke94]

A lot to consider and now am wondering if my thinking is right. Like I stated earlier, the power doesn't really start coming on until about 2200 rpm and pulls hard up to about 3000. I have always understood that diesels should be in the 1500/2300 range for peak power and torque. Thus I was thinking advancing is needed and figured that advancing the timing will bring the power band down in the rpm range. After the tranny shifts, unless I'm really on it, it dogs down until the rpm gets back up. I really noticed all of this when I moved to a higher altitude and turned the pump up so... Is my thinking off? Wouldn't be the first time.

 

[laserjock]

If you're used to other diesels, your rpm range is about right. These motors like to spin a little higher. I think the main deciding factor in where the torque curve is will be the cam grind.

 

[Black dawg]

That's great info and thanks. I watched a video on the pulse timing method and it looks and sounds a lot easier than messing with a glow plug. I know it needs to be advanced a little with the combo of the higher altitude and increased fuel. It's a little sluggish from a start and when it shifts gears, there's a little lag there and if I'm not ******* the throttle, she can smoke pretty good until the rpm's get up a bit. It's like the "power band" or whatever you want to call it really doesn't kick in until 2200 rpm or so. It might help the fuel mileage a little too without having all the unburnt fuel goin out the pipe. I'm hoping. haha

Your power should come in earlier. I would check the timing and then go from there, with lots of fuel and boost, I would shoot for 6 deg. PULSE method

 

[blacksmoke94]

Finally found a chart from FTE that fordf250hdxlt had posted earlier this year. Has some good info on this page. I agree that the power/torque should happen sooner. In looking at this chart, 6 deg sounds like a good middle ground.
http://www.ford-trucks.com/forums/1289475-luminosity-timing-question-discussion.html

 

[rockbender]

FYI, that chart is for Luminosity timing - it is ATDC.

Also, I recall a thread where one of the guys on the other forum had a built motor and on a trip where he was gaining elevation (went from WA to WY or MT or something if I recall) retarded his timing slightly to accomodate for the increase in altitude.

 

[sjwelds]

Interested to see the conclusion of this one. I had my truck checked after a turbo install and fuel adjustment, and it was at 9.9@2000. Bumped it back down to 8 and haven't really noticed a whole lot of difference. Maybe a bit quicker spool-up is all. Still, my diesel mechanic down the street says 6 deg is the setting he's had the best luck with. Mel and Russ both told me 8 to 8.5, which is where I'm at. Yet some guys on here say 9.5 is better for our newer ULSD fuel. So yeah, I don't know what or who to believe.