timing advance 1 tooth

[TFaucette]

i have heard that jumping a tooth on the pump gear and retarding the pump farthest away from the cylinder head will make it run lke a scalded dog and even make it lope real good, has anyone else ha any experienc with advancingtimming more than just the slots will alow?

 

[DVolk]

It will smoke like a sob and basicly fire on the exhaust strokethat kind of happend to me when i had the timming wrong on my 93 no power gain

 

[NIsaacs]

I don't think that is a good idea. You can advance the timing too much as it is with just the slots. I have my '91 advanced just enough to give a slight rattle when cold and the KSB is kicked in. When it warms up and kicks off, no more rattle.



Nick

 

[ENafziger]

Well, I'll quote myself to answer...

Static timing stock is 12. 5°, or about 1. 25 mm plunger lift.
Jumping one tooth gives 10° additional timing.
Bumping the pump 1/8" is approximately 3° advance.

Stock VE max dynamic timing via the KSB is 21 - 22°, or 2. 6 mm.
M&H dynamic timing spacer adds +10° dynamic timing, or 6. 4 mm at 1500 rpm pump speed, or 3000 rpm engine speed.

With reference to letters on the gear, marks set at E and O are stock. Set at C and O is one tooth advanced. To advance the timing, the gear should be bumped one tooth clockwise when facing the engine.

One reason to advance timing, is because in the OEM configuration, timing was set as a mediocre comprimise with respect to NOx and PM emissions, and was not necessarily optimized for BSFC. So, by advancing timing (some amount), the BSFC of the engine can be increased, at the expense of higher NOx.

The other reason for increasing timing, is to counter combustion phasing being pushed later and later from the addition of more fuel. Thus, the more fuel you add, the more you have to advance timing. This is seen by the guys running 400, 500, 600 hp that are jumped up to two teeth, pump to the head, KSB hotwired, etc.

Basically, if you're at stock fueling, a 1/8" bump by rotating the pump is probably as much as you want to go. As you increase fueling over stock, you can realize benefits from subsequently advancing timing more and more.

--Eric

 

[cerberusiam]

Unless you are running a different pump setup than stock and higher pop pressures advancing 1 tooth gets into the rattle zone too easily. A lot depends on how the pump is working and the settings on the hydraulic head for correct timing. Basically stock then just advance th epump.

 

[TFaucette]

afc, smoke screw, are maxed, power screw is at the point of as far as i can go before it wants to run-a-way, and stock fuel pin is rotated, future plans include denny t stage two fuel pin and POD's and 3200 spring (haven't had time to put in yet) really i wat it to lope and if increased timing does it, thats a lot cheaper than oversizeed lines.

 

[ENafziger]

Consult with the DMax guys, and maybe you can download one of their lope tunes for EFI Live.

 

[DVolk]

If you want it to lope by one of the Hot cams thats avalible from places like Colt cams etc

 

[Bob Beauchaine]

You can look at my sig for RWHP and mods. My pump is a built pump that I tweeked after the waranty was up. It is slightly over 1/8th, toward the head, probably 3/16 or so. I would hesitate to try 1 tooth advanced because I feel as if my power is good, I can generate smoke when or if I want and feel that too much advance is just not good for any internal combustion engine. Just my 2 cents worth.



Bob

 

[cerberusiam]

Unless you are running a different pump setup than stock and higher pop pressures advancing 1 tooth gets into the rattle zone too easily. A lot depends on how the pump is working and the settings on the hydraulic head for correct timing. Basically stock then just advance th epump.

You don't have large enough injectors or high enough fuel flow to need a 1 tooth advance. Too much advance will hurt more than help and it is way hard on pistons and HG's.

 

[DVolk]

I dont really see the point in gobs of smoke !!!! , whats going to happen is a real strict fedral mandated DEQ because of guys whom think its neat to fog cars at a stop light or what ever . Ever wonder why Cat Deisel had a heck of a time getting a engine to to pass the EPA standards is because of the Smoke , i can see a haze a fog no !!!!!!



Bob , if your ever my way id love to get a spring in my 92 but im chicken to do it my self , i got the springs here

 

[pwerwagn]

Consult with the DMax guys, and maybe you can download one of their lope tunes for EFI Live.

The Dmax EFI tunes wont work on his truck silly, Dmax's are 8 cyl.

 

[Ncostello]

Forget the 6 cyl/8cyl compatibility issue. EFI Live sells their product to Cummins owners now too. But I can't find the adapter to connect the cable to my first gen ECM. In fact I'm having trouble finding that too!



PS: Powerwagon... we joined at about the same time. And have nearly the same number of posts given the difference in join dates. We must be representative of a typical member who reads and posts. We are average members. lol

 

[Bob Beauchaine]

DVolk



Sorry for the delay re replacing your governor spring - had cataract surgery and was away from the boards for a while. I did not actually replace my spring but did watch it being done. It can be tricky but is not real hard to do. I will try to find a great step by step with pictures that I have and see if we can come up with something. I have had some experience with correcting problems once it is installed. The problems after install usually refer to indexing the pump properly and the full power screw - all external. I will be in touch about this.



Bob

 

[DVolk]

i definately dont want any drive ability issues