ZHooligan
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posted October 13, 2002 06:05 PM
You know psycho you are always so non technical. 
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Your Car Is Slow
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Fuck Nitrous...Got Boost?
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posted October 13, 2002 06:07 PM
I dont get it....perhaps some of us got better pumps than others.
Ive been spraying for quite some time now..and making alot more than 200hp...and the plugs show zero sign of fouling or damage....the trodes were a light brown.
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psycho1122
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posted October 13, 2002 06:33 PM
 Edited By: psycho1122 on 13 Oct 2002 19:34
THX! Z..... 
YCIS....why risk it and run your system "on the bubble"????
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ZHooligan
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posted October 13, 2002 06:47 PM
Again I have to inject that getting 200 with NOS versus gas only is not the same. The NOS is a secondary fuel source. The NOS is an anomaly in this equation. Or is essence we are talking apples and oranges. Try getting 200 plus horsepower without the NOS and then the pump according to psycho and Muzzy's data becomes a problem. I only know that at this moment I have the pump (suggested by my engine builder, he didn't make anything of of the sell) and my 1361 makes just a hair under 210 SAE without NOS. And it makes 263 SAE on the juice. And at this point if the pump helps or doesn't I'm not taking off!! And as bad as psycho hates Han's carbon snorkel I'm leaving it on because it is bitchin to look at and sometimes in life that's a good enough reason!!!
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To those who do not count their life in years, but in how life
has touched them in the past and how much it can hold in the
future; -- Youth is forever.
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psycho1122
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posted October 13, 2002 06:57 PM
I don't "Hate" the snorkel....I was very dissapointed when it took away ram pressure. I too love the way it looks....but I love the "X-Factor" of the ram pressure when running against "Higher Powered" bikes MORE! 
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Your Car Is Slow
Needs a job
Fuck Nitrous...Got Boost?
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posted October 13, 2002 07:22 PM
quote:
YCIS....why risk it and run your system "on the bubble"????
I was simply saying that the bike is still running RICH at 215 hp on spray...its obvious that using nitrous doesnt task the fuel system as much as "all motor" does. So saying that the fuel pump "is at its limit" at 200hp is a general and seemingly incorrect statement.
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fish_antlers
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posted October 14, 2002 07:53 AM
Well, it's Monday, and up here in Canada it's Thanksgiving. Luckily for once I have the day off! I have to say that this is highly entertaining... I have been sitting here with a cup of coffee reading this thread... damn.. .this place is better than a magazine subscription!
If only I could think of some way to carry this (computer) over towards the bathroom... ... some way to let me read it when I'm on the shitter... hmmmmmm  ...
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your car is slow
Needs a job
Fuck Nitrous...Got Boost?
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posted October 14, 2002 08:15 AM
Wireless man....
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ZHooligan
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posted October 14, 2002 04:32 PM
Wireless is the way!
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To those who do not count their life in years, but in how life
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future; -- Youth is forever.
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ra12r
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posted October 16, 2002 03:46 PM
Well, i have noticed that the simple questions, Doug has not been answered. Maybe he has been busy?!
Psycho, I have been doing some number crunching based on your WONDERFUL information. Now, i am not very smart but here goes......
1) 1cc = 1ml
2) Stock pump can move 360ml/min or 36ml/sec
3) 80% at 43psi injectors can move 5.33ml/sec which equals 196hp
4) 43psi fuel pressure maintained at both rates
I know that i am not very smart, compared to Doug, but 36/5 = 7!!! Which means the stock pump can pump 7 times more fuel than the injectors can flow in the same amount of time!!!!!!!!!!
Would someone more knowledgable check my math please!!! Cause i don't want to be wrong and run my engine lean. Thanks!!!
Maybe plugged injectors created your lean conditions?!?!
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psycho1122
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posted October 16, 2002 10:44 PM
Heres the best Info I can provide at this time......
Take the flow rate of each injector "Before cleaning" : 316.3 and Multiply that by 4 which equals 1,265.2 cc/min at 80% duty cycle.
Stock pump flows 2,200 cc/min.
The only info I do not have is how much more fuel flow there would be ABOVE 80%!
I did exceed 80% duty cycle to get the right A/F w/ the VP gas.
Also, when I bench tested the fuel rail w/ the regulator on, I noticed that I approached 50 psi (Compressed Air) before the Regulator started to bleed off!!
With those two pieces of info, I would not be suprised if I exceeded the fuel pumps flow rate.
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You say PSYCHO like it's a BAD thing!!
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psycho1122
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posted October 16, 2002 11:21 PM
Edited By: psycho1122 on 17 Oct 2002 08:02
Additional Info:
If rail pressure does get as high as 50 psi...The flow rate on the same injectors "Before Cleaning" rises to 339.10 cc/min or 1,356.4 for all 4 per min.
Here's the BIG one........At 90% duty cycle the B.S.F.C. in the same system rises to .55.....which was "only" good for 175.2 h.p.!!
This is important, in my 1270 map I am as much as +30 to +35 all over the map to obtain optimun A/F ratio!! My current B.S.F.C. is .48-.51 depending on Actual rail pressure AT 80% DUTY CYCLE!
W/O the pump,I could easily exceed 80% in these sectors, which would make my B.S.F.C rise. Good thing I have the HIGH Flow Pump in place.
W/ the pump It will help keep the B.S.F.C. as LOW as Possible.
ADDITIONALY...once you exceed 20% on your stock fuel injection system,(MAP) You NEED to address the ability of your fuel pump.
"Freeflow" rate (Which I was able to test) is alot different than "Static Flow Rate" after the rail builds pressure.
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kcadby
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posted October 17, 2002 09:33 AM
WOW?!?!?!
Can't we all just get along!?!?!?
Never mind...I don't need...let alone WANT TO get along with...SOME people...
Doug DID post IN DEPTH about the fuel pump issue after he hurt a motor LAST YEAR???
He (and Muzzys) don't "need" the sales they get from this...or any other board...IMO...
He just comes here to help people out with some things that are of "common interest to many of us" that come to these boards...
Thank you again Doug for sharing what I KNOW is time you could be spending on MANY other things in your life
Zhooligan...I talked to Mike about the rod bolt clearance deal (thank you )...I have all the clearancing done on this motor now
I could have and would have figured everything out on my own but...I LOVE knowing how "everyone else" does things too...saves time AND sometimes trouble...
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ZHooligan
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posted October 17, 2002 04:42 PM
Edited By: ZHooligan on 17 Oct 2002 17:47
Your welcome, glad to help when I can.
You know I do have to say that I have encountered a problem with my 1361. Since getting it together, tuned, the NOS and all of the other stuff, I have encountered a clearance issue in my helmet. The damn grin I get riding the thing around is putting a lot of stress on my cheeks from the Arai cheek pads. I'm not certain if I should get the porting tool out to releive the pressure or go to an open face helmet!!
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future; -- Youth is forever.
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ra12r
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posted October 17, 2002 10:52 PM
Kevin, point taken!!!
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fish_antlers
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posted October 18, 2002 06:13 AM
I , for one, as a mere internet layman would appreciate a shor technical answer from Doug.... lemme see if I can dig up the "hurt thread"..
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psycho1122
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posted October 18, 2002 08:43 AM
Doug WILL answer...........
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dougmeyer
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posted October 21, 2002 09:50 PM
Ra12
First, nothing personal here. You've made several comments regarding technical issues. Then you've made inferences about the company I work for and a product we offer based on an apparent lack of technical knowledge. I don't like that but I never fault someone for not knowing something, God knows there's an awful lot I don't know, but I try and learn before I speak. I've written a lot in magazines and on these boards answering questions. Every time I do that I learn, and one thing I learned a long time ago and something that I love about technical issues and engineering is how much there is to the most simple concept. There are layers and layers. All things mechanical are based on some pretty simple physical laws and basic chemistry. It's all physics and chemistry but, like medicine, there's a little bit of art in a job well done. Several of the other guys have just about explained all this but here's my nickel's worth.
First a little about pumps. A pump moves a fluid. It creates a flow with pressure. You can have a lot of flow at a low pressure or a little flow at a high pressure or high flow at a high pressure or low flow at low pressure. Different types of pump designs are best for each of these requirements. Examples- a centrifugal pump like the water pump on your bike creates a lot of flow at a low pressure. A gear pump like the oil pump can create a generous flow at a high pressure. Flow and pressure are generally related in that if you retard the flow, the pressure builds. Allow the flow to increase and the pressure falls. Pumps are spec'ed with a certain flow at a certian pressure. An easy example would be a bucket and a hose. Household water pressure is about 35 psi. Run a hose onto a bucket and you get a fair amount of water in there pretty quickly. Put your thumb over the end and the pressure goes up dramatically, and the flow (amount of water getting into the bucket over a given time) goes down. The "spray" is better, though (remember that). Each type of pump has it's limitations. Pinch off the flow in a centrifugal pump and it just spins freely with no problem (and no pressure). Restrict the flow in a good gear pump and the non compressability of the fluid can build pressure until something breaks or blows up. That's why there are pressure relief valves in oil systems. Pumps have a flow vs. pressure efficiency curve. Turn a pump too slow and flow is very small or zero, ask it to flow too much and pressure begins to drop- it can't "keep up", it cavitates or can't move the fluid fast enough to satisfy the requirement and the pressure drops.
The fuel pump in a ZX-12 is a kind of hybrid between a centrifugal vane pump and gear pump, called a friction pump. The electric motor (which is cooled by and submerged in the fuel) spins a thin plastic disc rimmed with small "teeth" like a very fine gear. This disc spins in a small plastic housing. The fuel goes to the periphery of the spinning wheel, is "grabbed" by the small teeth, spun around and forced out of the housing. It's not exactly a positive displacement pump like a gear pump, but it's not exactly a centrifugal pump either. It's a little of both. Problem is, it has a pretty small sweet spot of good flow and pressure. But, that shouldn't be a problem because a stock ZX-12 has a very predicable fuel requirement, and as you point out, the pump always spins the same speed. The pump NEEDS only to provide enough fuel to create no more than about 180 hp at no less than 47 psi. The pump does that just fine, but it does that at the very high end of it's efficiency curve. Ask it to provide enough fuel to create 200 hp and it can barely keep up. It can do it, but let it get worn or let the fuel get hot lowering the vapor pressure, or let the injectors get "sloppy" or let any number of other factors degrade it's performance and the flow (and pressure) drops. Less fuel means a leaner mix and soon, detonation and broken parts. How much fuel are we talking about here? The answer lies in something called Brake Specific Fuel Consumption (BSFC), which is expressed in pounds of fuel burned per horsepower per hour. Gasoline contains a pretty much fixed amount of heat energy that when "liberated" through burning is mechanically converted to horsepower. In a modern four stroke that amount is fairly constant at between .42 and .5 pounds of fuel per horsepower per hour. As an example let's pick .5 'cause the math is easy. 180 hp would require .5 pounds of gas for each of 180 the hp or 90 pounds per hour (PPH). A gallon of gas weighs about 6.2 pounds so that's 14.5 gal per hour or .24 gal. per minute at wide open. I'm told by Kawasaki engineers that the stock ZX-12 pump is a .65 liter per minute pump at 45 psi continuous. That converts to .21 gal per minute, 12.7 gallons per hour or 79 PPH. Ask it for more and you might not get it. Interestingly enough, that fuel delivery is enough for about 160 hp at .5 or at a more realistic .47, 164 hp. Guess what the average stock ZX-12 (2000/01) makes for HP? So, why not put in a different pump, one that is sized to deliver much more fuel at 50 psi. That way you are unlikely to be able to approach the point where it can't "keep up", where the pressure might drop a bit. The Muzzy pump flows over 350 PPH at 50 psi., enough for 700 hp. More than you need? Sure. But on a modified ZX-12 the stocker may very well be less than you need. There really isn't anything in between that fits the physical mounting requirements.
A few words about injectors and pressure may be in order here. An electronic fuel injector is a nothing more than an electromagnetically operated solenoid valve. There are two basic varieties, "high impedance" and "low impedance". In a high impedance injector, a current is sent to the magnetic coil in the injector which lifts a plunger and holds it open for a set period of time (in thousandths of a second or milleseconds) then cuts off and lets it close. Low impedance injectors are a little more sophisticated. They use a high current to quickly open the injector then a lower current to hold it there until closing. Better, but the "driver" circuitry and injectors are more expensive. The "open time" is expressed as a percentage of 100% (always open) and is called the duty cycle. A duty cycle of about 80% is preferred. Most OEM systems (including the 12) use the low impedance injector design. When you more flow from the pump, the only way to increase the fuel to the engine is to lengthen the injector duty cycle. A drawback to this is that the longer you hold a low impedance injector open, the longer the (high opening) current is flowing through the coils in the injector, creating electrical resistance and heat. This is a bad thing for the injector's health. Also, the longer you have the injector open the more you put the pump into the high flow, high pressure corner of the pump's output curve. What might help this? How about more fuel pressure? That would flow more fuel through the injector in a shorter time. That additional pressure will also make a better "spray" (see bucket example above). The pressure flow relationship is not linear. It takes four times the pressure to get two times the flow through a constant orifice. Remember, flow through an orifice is volume over time and the duty cycle controls the time. To increase the fuel flow needed on the ZX-12 when raising the power from 165 to 200, would require an 8% increase in flow through the nozzles. If it were to be done with pressure alone, without changing the duty cycle, that would take an increase in pressure of 36%. On a stock system that would necessitate an increase of fuel pressure up to 61 psi., something the stock pump is clearly not up to. Again, the "bigger" pump will allow for more fuel to be pumped at a given pressure. Increase the duty cycle (orifice size) and the pump can "keep up".
All this talk about fuel flow and quantities makes me think about how easy it is to determine these numbers now that we have electronic fuel injection. Back in the day, to measure fuel flow mechanically we used "turbine" flow meters that put a signal to a digital indicator. WAY back in the day we actually ran a carefully measured (by weight) amount of fuel over time on the dyno and measured the consumption to figure out the BSFC. Now days it's real easy. An injector is rated for a certain amount (in cc's) of fuel flow at a certain pulse width (in milleseconds) do the math and you get an accurate measurement of the fuel per "squirt". You get one squirt per injector every other revolution (1/2 the rpm). Do a little more math and you know exactly how much fuel you are using at a given rpm. Do this on a dyno, and you know how much fuel per hp and you have the BSFC.
So, are we cool here?
Doug
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RAC4IT
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Bergie
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posted October 21, 2002 10:10 PM
DAAAAYYYUM!!! Doug is the man! Seriously thank you for a very technical post delivered in terms we can all understand.
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frEEk
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ummm... yeah
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posted October 21, 2002 10:32 PM
not THAT was good reading. thx fer the lesson doug.
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ZHooligan
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posted October 21, 2002 10:36 PM
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To those who do not count their life in years, but in how life
has touched them in the past and how much it can hold in the
future; -- Youth is forever.
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frEEk
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ummm... yeah
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posted October 21, 2002 10:41 PM
holy shit! i posted my response soon as i finished reading this thread, but RAC4IT's post wasnt on when i read it! took me at least 26 min to read this fucker. damn...dis haer reedin ting is ard ma'um.
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psycho1122
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posted October 22, 2002 06:59 AM
THX! Doug..........
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your car is slow
Needs a job
Fuck Nitrous...Got Boost?
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posted October 22, 2002 07:34 AM
damn dude....you ever try out for jeopardy? My head hurts :/
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ra12r
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posted October 22, 2002 07:43 AM
WOW!!! I will have to read your (Doug's) reply several times to digest the info.
I will say that I don't mind "raising my hand in class" and asking or saying the wrong things. Pressing the envolope is neccessary at least for me, because i really needed to know the information and thank you Doug for explaining as everyone that reads through this thread will learn something.
My post will become less as i realized in this thread that my questions are CERTAINLY NOT well recieved on this board. Doug, i don't have any personal issues with you as i don't even know you, however i have not always felt warm inside about information that i have gotten from your company. Just because Muzzy's sells it or says it doesn't mean "TO ME" that it is neccessary or that it is the best or even different, but it could. {Even our current president is misleading us about some truths!!!!!!!!!! Ask any Marine!!!} The facts determine it for me. Technical information is not generally subjective, so i can only thank you for sharing the information. Thanks!
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