Timing question

IDIoit

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thanks for your help, I just installed the injectors last night and return lines and fired her up. the idle is really rough now and lacking power. almost a slight knock to it. i believe It is the timing from what you guys said. hard to rev up and clattery. I don't even want to drive it like this. I didn't think the injectors would make this much of a difference.


where did you get these injectors?
ive ran my engine from -9.5 to 11* and with a new IP and injectors it always ran smooth.
while power was all over the scale with this timing,
it never had a rough idle.
if you have a knock, there is an injector issue.
only 3 places I would ever trust with injectors for my engine, Typ4, CDI and R&D.
if you got them from diesel care, take extra care and place them in the garbage as hard as you can.
 

pelky350

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I've always wonder what timing actually gives the best performance all around? Oregon fuel injection told me they set it to 5' because that was where they see the best results for performance, Justin at r and d suggested I time it at 6' and I've heard of people timing their truck from 2' all they way up to 17'
 

NTOLERANCE

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where did you get these injectors?

if you have a knock, there is an injector issue.
.


I concur. I've changed injectors in my flying toaster several times. All of them were used. I've run into some really bad ones. Knocking after an injection change is a problem with the parts installed.

I bought a pop tester now. It's amazing what you can learn about injectors you've just pulled out of a "good" running engine.


Sent from my iPhone using Tapatalk
 

icanfixall

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For me I find 9.0 to 9.4 advance timing works very well on todays diesel fuel. When a member rents my meters I suggest you make several timing marks from 8.5 to 9.5 or 10.0 degrees. Then you can make a timing change and know what you are getting. It also solves the issue of renting the meter again for a long time. With these known timing marks you can remove the pump and re install it knowing it will be correct. You can even remove the heads but leave the injection pump gear housing in plACE AND STILL HAVE CORRECT TIMING WHEN YOUR DONE... Damn fat fingers "found" the caps key again.. Am not yelling nor do I look at the screen and type. I must look for the next key or I can't type...
 

Hydro-idi

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I've always wonder what timing actually gives the best performance all around? Oregon fuel injection told me they set it to 5' because that was where they see the best results for performance, Justin at r and d suggested I time it at 6' and I've heard of people timing their truck from 2' all they way up to 17'

At 17 degrees btdc, your glowplugs will disintegrate and god knows what else. Had mine running at 12 when I first bought truck and it did damage a few glows. I think anything between 5-10 is acceptable.
 

Macrobb

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I've heard of people timing their truck from 2' all they way up to 17'
Chances are the 17 degrees is using a different type of meter, like a luminosity probe.
Actually, that 17 degrees sounds like a number I came up with myself - using a luminosity probe(which reads actual firing timing), and a timing advance meter that won't go negative, so I read off the top edge of the harmonic balancer metal piece, instead of the zero-mark.

17 degrees read that way ends up being somewhere near 6 degrees with a ferret clamp-meter.


Remember that you can use a luminosity probe the same way as your ferret, but you have to add X degrees for the burn-time of the fuel. The actual burn flash should be after TDC by a couple of degrees, or therabouts.
 

Agnem

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I've always wonder what timing actually gives the best performance all around? Oregon fuel injection told me they set it to 5' because that was where they see the best results for performance, Justin at r and d suggested I time it at 6' and I've heard of people timing their truck from 2' all they way up to 17'

You have to be careful with what you hear, because some people don't have accurate meters, use the wrong RPM when they time, don't have a good pump on the truck, maybe dialed the offset iin wrong, etc. As Corey stated, we conclusively determined on HIS truck, that there is a small window for optimum performance between 8.5 and 9.5 degrees with the commercial diesel he was running. Verified with 2 different meters at the time, so we believe this is accurate. Retarding your timing can result in more BOOST, as you now have more burning taking place in the exhaust then before. However, having more boost, is not a guarantee of having more power when the variable is timing. Timing plays a huge part in power. I've timed hundreds of trucks, and can conclusively report that 8.5 to 9.5 has delivered the most seat of the pants power on all of them. These are stock engines with any variety of pumps or injectors. I've yet to find one that ran better retarded below 8 degrees.
 

icanfixall

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Thanks Mel for a well written factual real time response to timing. I have tested 11 degfrees and found it was tooo much. I did not ask for it and still wonder how I ended up with it. I even have a vid showing this. When members use my meters I make recommendations but in the end what an owner will use is their choice. Some times my guiding light is not a bright as theirs...
 

Julianq7

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thanks for all your responses everyone, I tightened one of the injectors a little more ad I think that did the trick. it drives how it use to now. No knock now, ad idle is a lot more smooth. I will still get it timed though for the best performance.
 
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