In your opinion, whats the best way to go? Obviously most would say to not leave the stockers. Extrude hone the stocks? Replace with aftermarket? another option?
Built motors and injectors.
- Thread starter SIKDMAX
- Start date
IIRC- every 1000 lb increase in pressure equates to 6% increase in volume?
So you kick up the pressure with the stockers to get the flow you need, in an effort to reduce the time required to get all the fuel in. better pumps, call higher pressure, fool or re-map pressures in EFI for even more pressure, etc etc
At some point you run out of time and need to get into a larger injector to reduce injection time, especially as RPM goes up. The bowl in the piston was designed for a reason, emission related burn management IIRC, they wanted the fuel shot in the hole. Somebody else knows better than I, but as we increase timing we start squirting the top of the pistons and chasing it down the hole.
Mike has done alot of work in this area...
OT- Anybody heard from Mike lately?
So you kick up the pressure with the stockers to get the flow you need, in an effort to reduce the time required to get all the fuel in. better pumps, call higher pressure, fool or re-map pressures in EFI for even more pressure, etc etc
At some point you run out of time and need to get into a larger injector to reduce injection time, especially as RPM goes up. The bowl in the piston was designed for a reason, emission related burn management IIRC, they wanted the fuel shot in the hole. Somebody else knows better than I, but as we increase timing we start squirting the top of the pistons and chasing it down the hole.
Mike has done alot of work in this area...
OT- Anybody heard from Mike lately?
Whatever injectors you go with, make sure they are "balanced".
You might be aware we hit 798rwhp on stock injectors (uncorrected) without using up all the fuel yet. And we made peak HP at 4400 rpm. Could we have made more? Yup. It was detuned 10% and had 2 shop rags stuck inside the intercooler tubes.
Without cracking pistons, and without backing off the timing.
I'm trying to play with bigger injectors again, and Guy is getting some built specifically for Casper.
The ones I have experience with are matched as nozzles. I can only speak for my results and those locally, but my balance rates were very good stock....and even better after having the injectors done. Not to mention lower EGTs.
People will argue the fact of matching the nozzle with the injector, but IMHO, there are too many variables once the injector is installed in the motor.
Eventhough there are people that have proven you can make HP with stock sticks, I have a similar opinion to Maxlly.
People will argue the fact of matching the nozzle with the injector, but IMHO, there are too many variables once the injector is installed in the motor.
Eventhough there are people that have proven you can make HP with stock sticks, I have a similar opinion to Maxlly.
Yes, Pat, I remember the rags picture :rofl:
Thanks for the helpful insight so far. It seems that my motor may have a cracked injector or two, so I need to get them out before I decide which route I may be going.
Of aftermarket stick companies, which are you guys running/most comfortable with?
Thanks for the helpful insight so far. It seems that my motor may have a cracked injector or two, so I need to get them out before I decide which route I may be going.
Of aftermarket stick companies, which are you guys running/most comfortable with?
As I understand it, there are different levels of "balance" these injectors can be taken to. Obviously, the mroe precise, the more expensive, and supposedly the mroe better they'll be.
My question of concern is to what precision are we talking about here on the "balancing"?? I extend that to you as well Big Dipper.
One particular I'm familiar with had a 5-point balance/match job done (don't ask particulars as to what that even means as I can't remember them now) and then was told that wasn't good enough and had them balanced/matched to, I wanna say, 100-points. Again, I can't remember the specifics of what the "points" are or mean but that's what I'm getting as far as a difference in the level of precision. To what precision are you all talking about getting them balanced to? The 5-point job is probably in the $500 range of cost for balancing and the 100-point, as you can imagine, is considerably more than that. So what are we talking about here guys?
C-ya
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The limit of your engine performance or life is dictated by the weakest cylinder. Let's say you want to run the engine at 90% of it's potential limit. If one injector flows 10% more, you need to tune it at 80% to avoid that one cylinder hitting it's limit and failing.
Or you want to tune for max power with no limit, let's say you lose 1% power if you overfuel or underfuel 1%. The better the engine balance, the more power it makes when tuned to the "sweet spot". The sweet spot is where adding or subtracting fuel reduces power.
Either way, the closer the cylinder balance is, the more power you can tune into it.
The best answer would be to be able to individually tune the cylinders like some racing ECM's do. But that currently is not an option. So we must do it mechanically by trying to get all the hard parts on the same page.
I used to believe big injectors caused bent rods and cracked pistons, but that was only partially right. Big injectors out of balance did.
Sorry to hear about cracked injectors, when i bought mine nobody had parts for them and wanted the tips back for core... so if the tip is bad you may have to purchase an injector to get core to get what you want or submit to core costs.
I can only suggest Industrial Injection. I can tell you it'll take some research so many different levels of flow (%based/litre based), method of hogging 'em out (EDM/Flow), number of holes, shims, spray angle... and finally testing. IIRC testing plays a part in accuracy, not everybody has an 8 hole bench IIRC. I waited until II purchased the new bench so they could test accordingly, otherwise (again IIRC) they test 6 (dodge) and plug the others in having to offer an average?
Making the choice was tough for me because I know fuel delivery is paramount, yet i don't understand the science. Buddy up with somebody who can help you out. Guy has access to tips, your prolly talking to him about hard parts already.
EDIT: Last i dealt with this the "standard" was big singles 40% over and twins 90-100%.
what makes you think tht. i dont see how and the heck tht would happen at least on your truck ?
Fuel in oil, compression test on my cylinders supposedly good, high balance rates, white not blue smoke.
I have no idea wtf the problem is, but something internal is wrong so its coming out and Im building it. Its either piston issues or injector.
Back on topic!:joker:
Back on topic!
:joker:
I would recomend Dynomite Diesel. They know what they aredoing there. They have tons of experience with Cummins injectors. You might want to give Paul a call there. He can tell you more about their program and what they are doing.
I sent my own stock tips to Extrudehone, did everything myself. As far as i knew at the time, other companys sent to them for honing, balencing and such i have no idea. Now as far as balance goes, im not sure if this is accurite enough but watching B/R with EFI or whatever, there all very close, much better than stock, if somthing was off, its because it broke an injector, never had an issue with the tips. It runs like a champ, idle is exellent with injectors this big, honed 50% over! These are ginormous for a stock turbo motor, i had them honed that much in anticipation of future mods, regardless there great, plenty of power gained on a stock tune, if driven somwhat nice it got about 20mpg, love them, saved a sh!t load of money, would do it again in a heartbeat! Its running a mouse-tweaked /McRat 20/20 tow tune now, nice puff of black if i floor it from an idle and it clears up to a haze and hauls ass. I run the piss out of it and she keeps on truckin. Just IMO and experiance!
Bumping this back up. Looks like Im going with Extrude Hone. What are peoples thoughts so far as %? Im thinking 30-40%.
Also, anyone else want to send in a set? If we get 2 or more sets then we all get a 10% discount.
Also, anyone else want to send in a set? If we get 2 or more sets then we all get a 10% discount.
Im gonna go with Extrude Honed. I have heard that they are the only people that still have the testing equipment that Bosch uses or somethin to that effect.Not sure on the details but I heard they do much better work for cheaper