My sciatic nerve is bothering me already, along with a bulged disk between my l4 and l5, and I have a long ways to go before I retire.
LB7: SAC 45 overs, who is running them?
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My sciatic nerve is bothering me already, along with a bulged disk between my l4 and l5, and I have a long ways to go before I retire.
Me too. Left leg goes numb and feeks like I have wet paper towels attached to my calf muscle. Getting old sucks and im only 39, physical labor has the tendency to do that though.
Me too. Left leg goes numb and feeks like I have wet paper towels attached to my calf muscle. Getting old sucks and im only 39, physical labor has the tendency to do that though.
I'm 28, mine started at 24. Pretty gay.
Good deal...glad it's working out for you. I'm still debating on if I should just go with the 45%s or the 65s like I planned from the beginning.
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I just had a microdistomy on my s1 l5. Try to put surgery off as long as you can. My l5 l4 and l4 l3 are both bulged. It is horrible!
I'm running a stock bottom end, so I'm not gonna turn the wick up very much, but these sacs flow like nobodies business once you start to add in some pulsewidth. I ran a 2250 with stock injectors as that was about all the fuel I could push, and keep it smokeless at 28 lbs of boost. I dropped down to a 1750 with the sacs(plan on stepping down to 1700), and from the but dyno it pulls alot harder. Small changes make a BIG difference with them once you turn the pressure up. Just dropping them from 1800 to a 1750 made a very noticeable change. The flow sheet I have for the 45's has them flowing not alot less than a 60 over exergy vco at the 160 1700 mark, wished the flow sheet from s&s included the next flow mark up like exergy does just to see the difference in them once the pressure is at 180 and pw is really opened up.
So it sounds like the tuning needs some more tweaks done to get it fine tuned, great, guess I'll cross that bridge eventually
I'll see how mine does when I can drive it, just have to solve the damn high rail pressure issue I'm having
I wasn't so worried about banging out the injector job cause of my crazy fishing schedule since I had my other truck but totaling it a couple weeks back changed that idea
I'll see how mine does when I can drive it, just have to solve the damn high rail pressure issue I'm having
I wasn't so worried about banging out the injector job cause of my crazy fishing schedule since I had my other truck but totaling it a couple weeks back changed that idea
Figuring out the tuning is a bit of a learning curve to say the least compared to vco nozzles. The biggest thing that blows me away is that I'm now spooling my turbo down at 1500-1600 rpm's just bringing the rpm's up in park. It took 1800 or more with stock injectors before my boost would move. And it shows in how it drives.
Im glad to see that you figured out the issue. But brings a huge concern about many tuners knowing how to tune these injectors. I wish they came in a stock size. Lately I have been seeing a lot of bosch remans fail with low miles. Damn lb7s
everything you have been mentioning is what i saw just going with bigger injectors in either VCO or SAC (45% over LB7 VCO and 100% over LLY SAC). throttle response quickens, EGTs drop some, turbo lights easier/quicker, and so on. I dont know if so much of what you are stating is really the difference in SAC or the fact they are 45% over from the stock ones you had. the stock SAC LLY injectors i ran in my truck for a year were lazy/lack luster of what i was use to with the LB7 45% over VCO's. these 100% overs in LLY form brought that performance back and i really cant see much gain yet (need more miles to see what MPG looks like in comparison to the LB7 stuff as well as towing performance). the LLY 100% overs were also easier to tune and clean up than the LB7s were but i also had a good foot hold of where i would be tweaking things from when i had the 45% over LB7 injectors in. The fuel smell at idle is better even at the same rail pressures as the previous injectors though.
That's crazy! I don't know a lot about tuning so I'm going to leave it to the pros. I'm happy for you.
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The SAC 45% LB7 injectors need to be tuned. I see time and time again other venders (not all but some) stating that they require no tuning and then low and behold the customer posts that they have a haze or raw diesel smell. Not to mention that you are adding fuel so you need to have it tuned in order to properly utilize the additional fuel or pull back fuel to get them as close to factory as you can.
What threw me compared to tuning VCO's was that I had to add pulsewidth down low. I've tuned a few with VCO's, so I was already expecting some haze and what not, but they respond COMPLETELY different. VCO's are semi predicteable once you figure latency in, but the SAC's have a completely different table. Instead of having to pull out across the board(obviously more as pressure goes up), I actually found that at roughly 50MPA theres a flipping point. Below you have to add exponentially, but above you have to subtract. It's a known factor that at idle the DURAMAX engine should consume roughly 8mm3 of fuel. With the SAC's it was showing fuel useage of roughly 9 at 35 mpa, at 50 it was right around the 7.5-8mm3 of fuel where it should be, but as rail goes up, the mm3 displayed sharply dropped to roughly 3.6-4 once you got to 160 mpa of pressure. Armed with this knowledge I was able to remap the fuel tables to get my throttle control back without having to remap 3 or 4 other tables. I also found that some of the LLY tables like pulse timing and rail pressure were MUCH better matches to these nozzles than the LB7 tables cutting down on how much I had to rework them.
I know James was second guessing your theory but I wonder how much of a difference the dual plane nozzle makes compared to a factory oversize LLY nozzle?
but I wonder how much of a difference the dual plane nozzle makes compared to a factory oversize LLY nozzle?
Tuning brought them down from the rough numbers I 1st posted to the pics I posted the 2nd time. I loaded in a mostly stock lb7 tune, and was having all kinds of problems, but the high balance rates worried me. Getting the tuning back to where it was idling where the ecm expected it to be idling got the balance rates pretty good, smoothed out the off idle shaking, got most all the grey haze out of it, and cleared up most all the fuel smell. I know the sacs don't burn as clean at idle compared to vco's, but they are very tempermental to tuning to say the least. SMALL, and I do mean SMALL changes make a big difference. Bumping idle timing from -3.6 to -2 was like night and day difference in idle smoothness and 3xhaust smell. Bumping rail pressure up to 40 at idle brought in a bit of a drone idling where 35 took care of it. They do need some tuning to run right as I was not inpressed with stock tuning at all.
They are not intended to be a bolt on item without tuning changes. They definitely are not as hard to tune as you are making it out to be. That's not a dig at you so please don't take it that way. They are different and get very good results. That's why I only use them unless the customer just won't spend the extra money. I think they are worth the effort and the payoff will justify the initial cost.
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It took me some getting used to to get the tables where I was happy with them. I know others would have just changed the tbiq to take care of the touchy pedal, but thats not how I like to do things. I set out to get my base file as close to stock with just pulse, timing, and rail changes so as to keep all the torque tables working like stock. It's just how I prefer to do it. The biggest thing that got me was I quickly found out the flow sheet I got did not match up with what I'm seeing in the tune.