injector haze

[dunes450r]

So i know everyone talks about injectors hazing, bigger injectors need more timing and the like. i know this has been talked about before.

my situation: I had POD's. I just installed DAP 5x14s with .020" crush washers. Previously my rig had a small amount of haze at idle when cold, and hazed when driving until warm. Now i would say the haze is about 2-3x as bad as PODs when cold, and there is a very small amount of haze when it is all the way up to temp.

i emailed DAP and they mentioned that using thicker crush washers would put my timing closer to non-ic patter injectors.

mods are: 12cm wg exhaust housing, non-ic crossover, getrag, 3.07s, HVlp lift pump with 12psi spring, fuel pin turned, 3200 spring, star wheel 1 turn down from all the way up, smoke screw all the way in, collar still on the fuel screw, timing is about 1/8" away from being against the head.

what are everyone's thoughts? i figured my haze would have gotten better with new injectors, but instead it got worse. i can tell i have more fuel at WFO, but i was looking for less haze and possibly better mileage.......

thanks

[RCCUMMINS89]

Do you have a way to check the pop pressures? Is your idle smooth?

I know on my mess, my truck hazes utterly ridiculous when it's cold, but doesn't haze at all when warm. Also, my idle timing plays a 100% roll in my warmed up haze.... the other "odd" part is even though I have smaller injectors and most see just the opposite but it takes loads of timing for my idle haze to go away. Now saying that, you shouldn't need more timing than where you have it...unless the pop pressures were set a little high for some reason (not uncommon on larger injectors, but I don't believe DAP does that).

[dunes450r]

my idle is smoother than it was with the PODs, but it hazes more. i don't have a way to check pop pressures. also noticed that i even get a little haze when accelerating lightly at lower rpms (not over fueled haze, blueish haze).

i'm not terribly happy with my situation, but am in contact with the manufacturer to try and solve my problems.

[RCCUMMINS89]

Please keep us updated on this. I am curious on why some people notice their injectors to be dirty... if it is a nozzle thing or an injector thing or a simple tuning thing (I don't believe it is a tuning thing)

[dunes450r]

i'll update it as it happens. i would like it to be a tuning problem or something since i'd like to limit the number of injector swaps i have to do

advancing the timing either by pump timing, or crush washer thickness should decrease haze? or somehow by spraying fuel into too small an area of the bowl its not combusting at 100% effeciency? just throwing out ideas now. i like the injectors, i'll like them even more if my mileage improves at all, or i could cut down on the haze

[dunes450r]

i swapped the .02" washers for .06" and no noticeable change in haze. i haven't tried backing my timing off yet, but will try to this week.

on a sidenote, i made a 300 mile round trip over the weekend to eastern oregon. got 17.6 mpgs on the way over the pass plus some driving around. then got 23.1 mpgs coming back down the pass home. round trip average of 19.3 mpgs much better compared to 14-15 with the 727 and pods, and 16-17 with gutbag and pods.

[RCCUMMINS89]

Have you tried putting your timing all the way to the head.

Rule of thumb.....

ON a cold engine, the more timing the worse the haze. (obviously not talking a little on a stock timed engine)

On a warmed up engine, it CAN BE just the opposite.


On my mess my truck is ridiculous with cold hazing and can be hard to start when it's real cold. When it's warmed up it's as clean as a prius...... when I back my timing off to what "most" 1st genners run it doesn't haze that bad when cold but doesn't get any better when warm.

[dunes450r]

i'm about 3/16" from the head right now. i get decent haze when cold and virtually none when warm. i'm looking for a happy medium with not much cold/warm. i'm going to back my timing off a bit soon too see if that helps with cold haze. then might get a timing spacer to help with timing when cruising