12v hazing at idol in gear ?

S

skyp951

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Apr 16, 2013
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Hi guys looking for some advise building 97 f350 12v Cummins conversion. crew cab flatbed 2wd farm truck daily driver. 12v has studs, 60# V springs, o ringed head, 4000 rpm gv springs. dd stage 1 sticks 4" down pipe back 3" down pipe, banks twin ram. custom intake, full gages, built e4od with stallion tq. Using the truck some and it is hazing at idol in gear smells like fuel as soon as put it in neutral it stops. didn't do it until I installed the new low stall TQ. injectors are new and the pump was bench tested and balanced, timing set about 18, fuel plate is ground, set about 1/2 way, star wheel and screw ? I asked for 1800 stall on the TQ. Do you think I can tune this out of it, maybe some different Dv's, timing change, AFC adjust? or am I going to half to get the TQ. stall adjusted? It didn't when the ford OEM TQ. was in there.
 
What injectors? You have good fuel pressure? Fresh fuel filter? Checked for air leaks in the fuel system?
 
dynamite diesel stage 1 air dog fuel pump 42psi on the fuel pressure gage.
 
I noticed a stronger spring in my AFC helping my idle haze some(air before fuel). But no load idle (5 speed). Look up some AFC tuning threads. Most likely converter related it sounds though.
 
Sounds like maybe your injectors have a low pop pressure. Were they installed at the same time? They may be first gen injectors,
 
I dont think the AFC even does anything for idle fueling. I think thats all injectors / governor springs / DV's. Not 100% sure on that.
On my truck, raising the pop off pressure above 270bar shifted some of the power from the top end of the RPM range to the lower end. Economy went up a little, haze went down some too. Youre probably shortening the injection event and lowering the effective timing by doing that but Im not sure by how much. Raising the hole count made the top end fall flat on its face but the low end was great. I assume this was less penetration at higher boost.
Some of that could be bad or beneficial depending on your setup. Lots of trial and error.
If you have a real tight converter, you can wind up with issues. Sure you may get a little more economy, but the engine is trying to make power at a lower RPM where the boost, intake velocity and swirl are lower. Smoke.
Youll wind up dialing back the AFC a bit to cut the off-idle smoke and that hits low end power.
 
Idle has nothing to do with the AFC. I'd look at getting your injectors cleaned and reset. Mine used to haze pretty bad and the smoke stung the eyes, had them cleaned and the pop's reset, made for a much nicer start and cut the smoke to nearly zero.
 
Well I guess I'll pull the injectors and send them to be balanced and have the pop set a little higher. These injectors are brand new less than 1000 miles on them and the shop that installed them pop tests them to make shore there were no dribbler's. I thought dynamite diesel were good injectors. does any one know an injection shop with same day drive in service that could set these injectors, south west Ohio area? Thanks for your help
 
Unless its hazing so bad you can't see I wouldn't even worry about it.
 
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