Alot has been done to my truck since I found this site. I set my timing when I did my kdp, and established my top dead center with an indicator (dial indicator with a long extension, hitting the top of the piston)...so I know I was right on the money when I set my timing to 16.5 degrees.

My stock timing was 12.5* just as the plate said on the side of the engine...so no slipping.

Observation: Anything below 1300-1400 rpm, I have significant lugging...something I never noticed when it was set at 12.5 degrees...normal???

Before you ask...I have not changed the fuel filter, prefilter screen, or overflow valve...yet...have all the parts, just have not gotten to it...would fuel restriction cause lugging??

Lastly...my afc spring is real loose...not all the way, but close...could the boost be causing the governor to bounce...hence, lugging? Doubt it, but just wanted to ask.

Other then that...anything about 1500 rpm and up...it runs like a raped ape...so I don't think I am dealing with an injector issue. Also, idle is perfect, not a miss or anything.

Need some help understanding this lugging...as I did not experience it before I began bombing.

 

u lose a lil bottom end with timing advances and gain top end...slide the afc housing fully forward and turn the star wheel forward and u'll get plenty of low end back

 

T...

Just to refresh my memory...pushing the star wheel fully forward...means back it off all the way? So there is no spring tension?

Btw..afc housing is fully forward (towards the radiator).

 

you loosen the tension on

the spring, to get more fuel to the pump, the tighter the spring is, the less fuel you have, IE more restriction, just the inverse can be expected from loosening the spring..

Tx

 

Sorry guys...had to update my sig...hope that does not effect your suggestions...as I assume it won't, as we are dealing with low rpm fueling.

Sounds like the afc spring...no problem, will adjust tomorrow.

 

yeah when looking at the pump from the drivers side ..u will turn the star wheel towards the motor

 

Yes, this is normal. Once you increase the power, you do not want to run it below 1500-1700 rpm. The clutch will be much happier and the engine is giving you more.
If you plan to add GSK, the timing can go even more.
Fixed mechanical injection is a bugger compared to the ISB guys when it comes to optimal timing at a given engine rpm.

 

Thanks guys...significant improvement. Checked my records, and embarassed to say...been 40k miles since my fuel filter change...shame on me. So this weekend, new fuel lines (5/16" & 3/8"), overflow vlave, screen kit, and fuel filter. Expect a new truck afterwards.