Info: bigger injectors: what are they like @ idle?

bluessmax

bluessmax

Tabasco Injected!
Nov 4, 2010
1,143
6
38
Lake Charles, la
I wouldn't ever do any less than 60% injectors... With how far technology and tuning has come, for sure up to 100% can be tuned with no smoke at idle and even driving.
 
H

Hot COCOAL

May the farce be with you
Jun 9, 2012
4,433
0
0
:doh: i figured I'd get mixed results on the this
I only want to roll some coal in the race tune :coal:
:patriotic2: thanks everyone i will probably be using rob c for tuning,
:confused: I'm still as unsure as ever, fortunately i have some time, i was planning on getting one new injector at a time over the next 6-8months, then have the whole set of new injectors worked by exergy. So keep the input going please :D
If anyone would like to share tuning tips about keeping idle emissions at bay please keep it civil if there is discrepancies between one another:):)

Thanks again all :hello:
 
Last edited:
H

Hot COCOAL

May the farce be with you
Jun 9, 2012
4,433
0
0
guideline for thread....

I have noticed that all of the posts where you guys are NOT experiencing strong idle emissions, are from guys runnin twins....right? Maybe add that info when you post, if you dont mind please .
And for informational purposes only, this is kinda what i am looking for now

Me for example-

Engine: lbz
Injector size: stock
Turbo(s): stg 2 garrett 4094vgt
Tuning: efi live from rob, built trans, turbo modified
Smoke? No smoke any tune, slight haze on race tune

Synapses: i need bigger injectors!
 
H

Hot COCOAL

May the farce be with you
Jun 9, 2012
4,433
0
0
Your cusins truck is really strong at idle in all the tunes???
Damn thats a big kit too
 
delong_1

delong_1

<< my work
Dec 5, 2008
1,282
0
0
38
Arvada, CO
Also compression ratio, elevation, temp, turbos, etc also play a big role in all of this. I know this even moving from 4300' to 5800'. Made things even more difficult to be "clean"
 
H

Hot COCOAL

May the farce be with you
Jun 9, 2012
4,433
0
0
I live @ appx 350ft above sea level. I travel all over, so probably 50% of my time is above 4000ft and the the other 50% im home in the dense air at sea level. My tunes are from rob, he tunes @ like 5000ft i think, whatever elevation Boise is, what affect would this have, if any, to my end results of my tune?
 
DAVe3283

DAVe3283

Heavy & Slow
Sep 3, 2009
3,727
296
83
Boise, ID, USA
Engine: LB7
Compression: Stock (17.5:1)
Injectors: 60% over by Industrial Injection
Turbo: S371 by EPR
Tuning: Mine, I only run a race tune. EGTs are fine with the S371, even towing!
Trans: Built by MikeL, tweaked stock TCM tune by me.
Elevation: 0 to 2,500 feet. I will tune any smoke out at higher elevations, as soon as I am at a higher elevation for a few days.

No smoke under 50% throttle at all. At WOT, it will smoke during spool, but that is because I have not finished dialing in the MAF limiters. Once the turbo lights, it is completely clean. If you are getting mid-throttle smoke, raise your shift points just a hair. Or for you lucky guys with VGTs, just command more boost!

I mentioned idle smoke and smell (and how I eliminated it) in previous posts.

Having a tuner at higher altitude is good, because they know how it affects things, and what modifier tables to adjust. I tuned my engine when it was stock at 5,300 feet, and at sea level. Got rid of all the smoke between those two extremes. Once you get your tuning close, it is really just one table to adjust, at least in the LB7.

I talked with Rob a few weeks ago, and he said they are trying to make all their tunes smoke free (unless otherwise requested). He should be able to get your truck running how you want, even with large injectors.

And finally, I recommend at least 60% over injectors. I get the same mileage (a hair better on the highway due to less restrictive intake/exhaust, and a hair worse in town due to slightly higher shift points). Idle smoke and smell is gone at the flip of a switch (or all the time if you prefer). Drives great. I kind of wish I had gone 100% overs.
 
adeso

adeso

wait, what?
May 30, 2011
1,569
0
36
Minot, ND
Hot COCOAL said:
:doh: i figured I'd get mixed results on the this
I only want to roll some coal in the race tune :coal:
:patriotic2: thanks everyone i will probably be using rob c for tuning,
:confused: I'm still as unsure as ever, fortunately i have some time, i was planning on getting one new injector at a time over the next 6-8months, then have the whole set of new injectors worked by exergy. So keep the input going please :D
If anyone would like to share tuning tips about keeping idle emissions at bay please keep it civil if there is discrepancies between one another:):)

Thanks again all :hello:
Click to expand...

Just save up and get them all flow balanced....
Twins have nothing to do with idle smoke or smell at idle
Comp plays into it a lot, for your goals I would keep it up to stock levels, don't go any lower than a cut LB7 piston
No mater what they are going to smell more at idle, there is stuff you can do to help it a lot but still going to have some.
I would not try to run small sticks, you can't keep the pw and timing where you really want it pushing a huge amount of fuel. 800 HP on 30% is harder on the engine than 800 HP on 60%
 
ecc_33

ecc_33

Junior Member
Aug 10, 2006
1,925
0
0
39
Amanda, Ohio
my truck is around 14-1 to 14.5-1 compression and under 40* outside it is smokey until warmed up. Once warm its fine though
 
DAVe3283

DAVe3283

Heavy & Slow
Sep 3, 2009
3,727
296
83
Boise, ID, USA
adeso said:
No mater what they are going to smell more at idle, there is stuff you can do to help it a lot but still going to have some.
Click to expand...
I disagree. My truck smells less now that it did stock right after pulling the cat. On a scale of 1 (smells like nothing/propane) to 10 (raw diesel), this is what my truck smelled like:

Stock, with cat and EGR: 1
Stock, with cat no EGR: 2
Stock, no cat no EGR: 6
60% overs, stock idle tuning: 8
60% overs, idle tweaks (timing and pressure): 5
1982 6.2L diesel: 8-9 depending on temperature

So it is better than stock with the cat yanked. The biggest change in smell for me was when the cat got removed. I think if I put a cat back on now, I could get the smell back to the 1-2 range. But I'd also give up some highway mileage. :( Can't have it all, I guess.
adeso said:
I would not try to run small sticks, you can't keep the pw and timing where you really want it pushing a huge amount of fuel. 800 HP on 30% is harder on the engine than 800 HP on 60%
Click to expand...
I agree 100%.
 
Last edited:
duratothemax

duratothemax

<--- slippery roads
Aug 28, 2006
7,139
10
0
Wyoming
My 40% Dipper injectors dont smoke at idle when warm, but they definitely do smell more than a stock truck. As the truck warms up, it gets better, the smell really isnt bad, but you definitely do notice it.

just as quiet as stock injectors, starts fine in sub-zero temps. I have a stock LBZ long block in my truck, so 16.8:1 compression ratio vs stock 04-05 LLY at 17.5:1.

Also, if its below 50* or so at cold start, they do haze blue-ish and the smell is pretty strong and makes your eyes water if you are standing around the back of the truck before its warmed up.

Whats weird though is my buddy's fully-built LLY with 125% over injectors doesnt smell any worse than my 40%. His 125% sticks have zero smoke at idle, but obviously when driving at part throttle/lower boost, they are somewhat smokey.
 
juddski88

juddski88

Freedom Diesel
Jul 1, 2008
4,655
120
63
Chesterfield, Mass.
I would have to say that injector rated-size is not constant, therefore your 60 overs may be the same as someone else's 40 overs...just an example: exergy>extrude honed

DAVe3283 said:
Engine: LB7
Compression: Stock (17.5:1)
Injectors: 60% over by Industrial Injection
Turbo: S371 by EPR
Tuning: Mine, I only run a race tune. EGTs are fine with the S371, even towing!
Trans: Built by MikeL, tweaked stock TCM tune by me.
Elevation: 0 to 2,500 feet. I will tune any smoke out at higher elevations, as soon as I am at a higher elevation for a few days.

No smoke under 50% throttle at all. At WOT, it will smoke during spool, but that is because I have not finished dialing in the MAF limiters. Once the turbo lights, it is completely clean. If you are getting mid-throttle smoke, raise your shift points just a hair. Or for you lucky guys with VGTs, just command more boost!

I mentioned idle smoke and smell (and how I eliminated it) in previous posts.

Having a tuner at higher altitude is good, because they know how it affects things, and what modifier tables to adjust. I tuned my engine when it was stock at 5,300 feet, and at sea level. Got rid of all the smoke between those two extremes. Once you get your tuning close, it is really just one table to adjust, at least in the LB7.

I talked with Rob a few weeks ago, and he said they are trying to make all their tunes smoke free (unless otherwise requested). He should be able to get your truck running how you want, even with large injectors.

And finally, I recommend at least 60% over injectors. I get the same mileage (a hair better on the highway due to less restrictive intake/exhaust, and a hair worse in town due to slightly higher shift points). Idle smoke and smell is gone at the flip of a switch (or all the time if you prefer). Drives great. I kind of wish I had gone 100% overs.
Click to expand...
 
You must log in or register to reply here.
Top Bottom