Why??? I mean....why take the risk for a mere 10hp increase of leaning out and risking the engine.
Just get it to run safe. I wouldnt run 13:1 ratio even on 100+ octane fuels
Larger Injectors For Forced Induction
- Thread starter LinuxRacr
- Start date
Why??? I mean....why take the risk for a mere 10hp increase of leaning out and risking the engine.
Just get it to run safe. I wouldnt run 13:1 ratio even on 100+ octane fuels
I know some places put forward the concept of 13.2:1 being max torque but from everything I've done I disagree. One of my professors in college actually did his thesis on that and water injection... he wrote the book on it basically... he advocated 12.5:1. From most of the research I've done (and I have done engine test stand research as well.) peak output based on AFR alone is between 12.5 and 12.8:1 AFR's. However, that doesn't translate always for peak total output. You often can obtain more output by going richer and running more timing etc.. all about finding the balance for your car and the compression ratio you have etc.
Also, peak power is NOT made on the threshold of detonation, it is actually several degrees before in most cases. The TRUE peak power occures when you hit your highest MEP (mean effective pressure) inside the cylinder at between 12 and 14 degrees after top dead center. so your timing needs to target that. Now, since most people don't have pressure taps on their cylinders to ID that exact situation etc, it's much more trial and error, but the simple fact is maximum advance doesn't ensure that you do hit that point, you CAN over advance a motor and lose power.
The only thing pure water injection gains you is greater resistance to pre-ignition, and a slightly cooler charge which can allow you a LITTLE more advance... most people add methanol which then ups your octane which then allows you more advance... but again... all goes back to the theory above, which your intent doesn't match, so I'd suggest re-evaluating your approach.
Also, peak power is NOT made on the threshold of detonation, it is actually several degrees before in most cases. The TRUE peak power occures when you hit your highest MEP (mean effective pressure) inside the cylinder at between 12 and 14 degrees after top dead center. so your timing needs to target that. Now, since most people don't have pressure taps on their cylinders to ID that exact situation etc, it's much more trial and error, but the simple fact is maximum advance doesn't ensure that you do hit that point, you CAN over advance a motor and lose power.
The only thing pure water injection gains you is greater resistance to pre-ignition, and a slightly cooler charge which can allow you a LITTLE more advance... most people add methanol which then ups your octane which then allows you more advance... but again... all goes back to the theory above, which your intent doesn't match, so I'd suggest re-evaluating your approach.
kyle's protege5
Member
- :
- 2002 MP5-T
Point taken by you both. I was only stating the plan, and what I was guessing I was gonna do. I do plan on tuning by AFR to start and when its all broke in and dialed in as good as I can that way, its off to the dyno for the final tuning.
And I will be running premium gas all the time and 50/50 water methonal.
You two are pretty darn knowledgeable, you wanna take at look at this thread and give me your opinion as to why my motor seems to be stuck?
http://www.mazdas247.com/forum/showthread.php?t=123678197
And I will be running premium gas all the time and 50/50 water methonal.
You two are pretty darn knowledgeable, you wanna take at look at this thread and give me your opinion as to why my motor seems to be stuck?
http://www.mazdas247.com/forum/showthread.php?t=123678197
Enough of the BS. Stock injectors are insufficient.
Use this to figure out what size injectors you need.
http://www.rceng.com/technical.aspx
Use this to figure out what size injectors you need.
http://www.rceng.com/technical.aspx
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kyle's protege5
Member
- :
- 2002 MP5-T
cool, thanks for that link. Looks like i'm gonna need bigger injectors now!
the calculators tend to be significantly over conservative. Plain and simple with a Walbro pump and stock injectors you can make it to about 220 whp without much issue... if you ned to go over that you need bigger... don't understand why the confustion for so many people. The reason some of the Haltech guys and others struggle though is because they are not full sequential systems... and because of that the calculator also will not approximate it properly... non-sequential systems hit max dutcy cycle sooner and are less efficient in fuel distribution.
That statement about Haltech not being able to fire injectors in sequential order and not being fully sequential is false and ignorant.
E6X and E8 are able to fire injectors in sequential order.
I know you are an advocate of the Microtech, but do not speak on a system that you do not use.
RC Engineering has been supplying aftermarket fuel injectors to racers for a while, so they know their fuel injection.
As for being conservative, you should not run your fuel injectors over 80% duty cycle because you will run the risk of the injector not being able to open and close quickly enough, which causes the injector to float half open. Not good or safe at high rpm/loads.
E6X and E8 are able to fire injectors in sequential order.
I know you are an advocate of the Microtech, but do not speak on a system that you do not use.
RC Engineering has been supplying aftermarket fuel injectors to racers for a while, so they know their fuel injection.
As for being conservative, you should not run your fuel injectors over 80% duty cycle because you will run the risk of the injector not being able to open and close quickly enough, which causes the injector to float half open. Not good or safe at high rpm/loads.
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Take your own advice and don't jump to conclusions about what I do and don't use... I have tuned a fair number of Haltech's and fixed a few Haltech installations as well. I'm well familiar with the E6X and F10 systems. I have not had experience with the E8. I have also tuned a few of the E-manage and others.
The E6X from what I remember and can see trying to double check against spec sheets etc can only fire in semi-sequntial firing which means it fires the same as wasted spark ignition... pair injectors firing at a time. Since you then have to fire every revolution instead of every other revolution you run out of duty cycle quickly (unless they are firing a bridged semi-sequential and firing every other rev but doing closed valve firing... which is a whole 'nother thing to discuss...). And from what I recall with the systems I worked with etc that was the case, and it's what I'm finding from spec sheets and the like I'm pulling up in some quick searches. Now if it's not, then show me where it says otherwise and I'll happily stand corrected. We had the same "issue" on the Microtech early on and had them correct it for us to get to full individual 4 channel sequential.
I also remember coming across it at some point, but will have to dig to verify it, about not running with a cam sensor, and if you do that there is no way in hell you can run sequential.
I also don't see any issue with either of the quotes you posted... we did 260 whp on a car with stock injectors... and I said simply that with a walbor and stock injectors I believe it to be safe/fine to go to 220+ whp... we were having leaning problems at the 260 that I wouldn't recommend.... so I don't understand your point in posting those quotes.
And yes, while I sell and advocate and prefer the Microtech, I've worked with every system on the market for the Protege, and know how to tune, install, and run all of them.
The E6X from what I remember and can see trying to double check against spec sheets etc can only fire in semi-sequntial firing which means it fires the same as wasted spark ignition... pair injectors firing at a time. Since you then have to fire every revolution instead of every other revolution you run out of duty cycle quickly (unless they are firing a bridged semi-sequential and firing every other rev but doing closed valve firing... which is a whole 'nother thing to discuss...). And from what I recall with the systems I worked with etc that was the case, and it's what I'm finding from spec sheets and the like I'm pulling up in some quick searches. Now if it's not, then show me where it says otherwise and I'll happily stand corrected. We had the same "issue" on the Microtech early on and had them correct it for us to get to full individual 4 channel sequential.
I also remember coming across it at some point, but will have to dig to verify it, about not running with a cam sensor, and if you do that there is no way in hell you can run sequential.
I also don't see any issue with either of the quotes you posted... we did 260 whp on a car with stock injectors... and I said simply that with a walbor and stock injectors I believe it to be safe/fine to go to 220+ whp... we were having leaning problems at the 260 that I wouldn't recommend.... so I don't understand your point in posting those quotes.
And yes, while I sell and advocate and prefer the Microtech, I've worked with every system on the market for the Protege, and know how to tune, install, and run all of them.
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Fallacy 1
You haven't used every system. You haven't used/tuned a Unichip or the E8.
Fallacy 2
Page 119 E6X manual.
http://haltech.com/downloads/e6xv303v2Windows_manual.pdf
A. I know this system better than you.
B. The car is equipped with a CAM sensor, you are able to set it up to run sequential, you just didn't know it could.
C. The Protege is 4 cylinder and the E6X controls 4 seperate channels.
Fallacy 3
The point of those quotes is what you are telling people is unsafe and not recommended. It is beyond what the stock injectors can support SAFELY. The only way you probably did it was using an aftermarket FPR to bump up the fuel line pressure.
Finally, that is great you believe that of yourself. You are not as good as you think you are. Knowing the subject and knowing it well are on 2 ends of the spectrum.
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Now we know why your car pops at start up.
You have your new project. Rewiring time.
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I really don't have the time to get in to a pissing match. So I'm over and out on this one after these points So you have an open forum to crucify me as you so please or believe on this one....
1) The unichip is basically discontinued from what Ken tells me, and I haven't seen an authorized vendor selling the E8 or anyone using it... so I didn't consider them to be "on the market" and the E8 software is a derivative of the Halwin software which I'm familiar with... and the wiring isn't going to be any different from a technical standpoint. You ARE more familiar with the Haltech availability, so if the E8 is being sold by you or another... then my statement should have been "Most" of the systems.
2) Never said you didn't know the system better than me.
3) I said I stand happily corrected if it can run sequential. You've stated it does...
4) Linux and the other early adopters ran it the way he does... so I was correct in indicating that some Haltech users could be coming up short on fuel relative to what they should be because of that setup. He's not the only one running that way I'm sure.
5)You don't know what duty cycle we were or weren't running, so you can't say if the setup was safe or not. Also, you don't know what the efficieny of the motor was either. That's the problem, you put your faith in the theory of the stupid calculator online and don't pay attention to any of the rest of the factors. Yes, they are a great conservative baseline, but they are also in the business of selling injectors so they are going to give you a more conservative estimate so you need bigger injectors. If you do the math yourself with more info you'll find that they typically recommend about 25% to 50% bigger than necessary and bigger than you'll see on an Evo or other factory vehicle. But unless you know the actual VE and natural efficieny of your motor and it's MEP and the like to calculate it's given output then you can't with any reasonable accuracy say how much horsepower will come out of the injectors set to it because you can't say with what efficiency the system is operating and converting the usable energy of the volume of fuel to horsepower. In other words, to size an injector properly to your vehicle you need to know more about what it's characteristics are... the calculators are largely conservative shots in the dark. They also assume maximum open time is at/near redline, which again is garbage and almost NEVER the case because of the dropoff in VE toward redline... not to mention holding peak boost to the last moment etc.. and gives no value as to where peak horsepower is or a host of other factors... again a shot in the dark.
Also... the 80% duty cycle idea is a bit of useless "knowledge" that many cling to as the gospel of injectors rather than to actually understand what the point involved behind that "guideline" is. Simply put an injector needs a certain amount of time to be able to close to not float. That's typically a given number of micro seconds/fraction of a millisecond. As long as that value remains in place you can safely run much much higher duty cycles than 80%, just depends on the quality of the mechanics of the injectors. For simple example, if an injector has a response ability such that it can close at the operating pressure in say 1 millisecond... (much much longer than it would really need, but an easy number to work with). And you are running at a low rpm where a cylinder needs a lot of fuel, lets say 3,000 rpm's which should be about 20 milliseconds per revolution (as long as I didn't botch the math trying to do it quickly here)... you can run as much as 19ms of open time and still give the injector more than enough response time. In other words you are running at 95% duty cycle very much safely. Similarly, if you are using an older or cheaper injector you could find that at 6500 rpm's you can't even run 60% duty cycle safely. So rather than using generic calculators it's better to actually know what you are doing in the first place and what physically is involved. And before you go and rip the calculations above as implausible etc... yes the 3000 rpm one is not real relavant to actuality because of the loads etc involved, but was illustrative in it's intent.
I also know for a fact that on the 220 horse tune we did originally we were under the golden cow 80% recommendation throughout the width of the power band, on stock fuel pressure, with a pierberg inline as the only adjustment to the fuel system. And running a clean 12:1 through most of the boost ranges.
Also, a floating/half open injector typically leads to fuel leakage and additional richness which is in and of itself fine (as long as you aren't tuning to that condition). The bigger issue is that continual use in this range and for extended periods can burn out the coil in the injector... THAT is the real problem, not the bit of extra leaked fuel. But the extra leaked fuel can be a problem if the tuner doesn't pay attention to the condition or isn't aware of the limitations of the injector and manages to run a cylinder out lean because of a single AFR reading from 4 cylinders and the lack of consistency cylinder to cylinder that can be present at that time.
Lastly, seriously, chill out... this is an internet forum you are rapidly sounding more and more like MPNick and the hissy fits him and Dana used to go through on a regular basis... we both have better things to be doing.
1) The unichip is basically discontinued from what Ken tells me, and I haven't seen an authorized vendor selling the E8 or anyone using it... so I didn't consider them to be "on the market" and the E8 software is a derivative of the Halwin software which I'm familiar with... and the wiring isn't going to be any different from a technical standpoint. You ARE more familiar with the Haltech availability, so if the E8 is being sold by you or another... then my statement should have been "Most" of the systems.
2) Never said you didn't know the system better than me.
3) I said I stand happily corrected if it can run sequential. You've stated it does...
4) Linux and the other early adopters ran it the way he does... so I was correct in indicating that some Haltech users could be coming up short on fuel relative to what they should be because of that setup. He's not the only one running that way I'm sure.
5)You don't know what duty cycle we were or weren't running, so you can't say if the setup was safe or not. Also, you don't know what the efficieny of the motor was either. That's the problem, you put your faith in the theory of the stupid calculator online and don't pay attention to any of the rest of the factors. Yes, they are a great conservative baseline, but they are also in the business of selling injectors so they are going to give you a more conservative estimate so you need bigger injectors. If you do the math yourself with more info you'll find that they typically recommend about 25% to 50% bigger than necessary and bigger than you'll see on an Evo or other factory vehicle. But unless you know the actual VE and natural efficieny of your motor and it's MEP and the like to calculate it's given output then you can't with any reasonable accuracy say how much horsepower will come out of the injectors set to it because you can't say with what efficiency the system is operating and converting the usable energy of the volume of fuel to horsepower. In other words, to size an injector properly to your vehicle you need to know more about what it's characteristics are... the calculators are largely conservative shots in the dark. They also assume maximum open time is at/near redline, which again is garbage and almost NEVER the case because of the dropoff in VE toward redline... not to mention holding peak boost to the last moment etc.. and gives no value as to where peak horsepower is or a host of other factors... again a shot in the dark.
Also... the 80% duty cycle idea is a bit of useless "knowledge" that many cling to as the gospel of injectors rather than to actually understand what the point involved behind that "guideline" is. Simply put an injector needs a certain amount of time to be able to close to not float. That's typically a given number of micro seconds/fraction of a millisecond. As long as that value remains in place you can safely run much much higher duty cycles than 80%, just depends on the quality of the mechanics of the injectors. For simple example, if an injector has a response ability such that it can close at the operating pressure in say 1 millisecond... (much much longer than it would really need, but an easy number to work with). And you are running at a low rpm where a cylinder needs a lot of fuel, lets say 3,000 rpm's which should be about 20 milliseconds per revolution (as long as I didn't botch the math trying to do it quickly here)... you can run as much as 19ms of open time and still give the injector more than enough response time. In other words you are running at 95% duty cycle very much safely. Similarly, if you are using an older or cheaper injector you could find that at 6500 rpm's you can't even run 60% duty cycle safely. So rather than using generic calculators it's better to actually know what you are doing in the first place and what physically is involved. And before you go and rip the calculations above as implausible etc... yes the 3000 rpm one is not real relavant to actuality because of the loads etc involved, but was illustrative in it's intent.
I also know for a fact that on the 220 horse tune we did originally we were under the golden cow 80% recommendation throughout the width of the power band, on stock fuel pressure, with a pierberg inline as the only adjustment to the fuel system. And running a clean 12:1 through most of the boost ranges.
Also, a floating/half open injector typically leads to fuel leakage and additional richness which is in and of itself fine (as long as you aren't tuning to that condition). The bigger issue is that continual use in this range and for extended periods can burn out the coil in the injector... THAT is the real problem, not the bit of extra leaked fuel. But the extra leaked fuel can be a problem if the tuner doesn't pay attention to the condition or isn't aware of the limitations of the injector and manages to run a cylinder out lean because of a single AFR reading from 4 cylinders and the lack of consistency cylinder to cylinder that can be present at that time.
Lastly, seriously, chill out... this is an internet forum you are rapidly sounding more and more like MPNick and the hissy fits him and Dana used to go through on a regular basis... we both have better things to be doing.
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Maxx Mazda
Contributor
- :
- Stock P5
On a non sequential injection setup, don't you have more headroom on the injectors? Sure, you need to fire them twice, so the duty cycle agrument is valid, however because they are fired twice per cycle of the engine (once per crank revolution, but each engine cycle is 2 crank revolutions) you only need the injector to be open half as long each time.
There has been a LONG standing debate on sequential vs. multipoint injection, and the benefits of each. Frankly, there weren't enough benefits to sequential to justify the switch. I think someone got a 5% gain, and had to mess with the injector phase angle quite a bit to get there.
Sam, when you wire them up sequential, do you run the home or trigger signal wire to the CMP sensor signal? It says in the manual somewhere, but do you leave it set as motronic, or do you use the "mazda A" preset?
There has been a LONG standing debate on sequential vs. multipoint injection, and the benefits of each. Frankly, there weren't enough benefits to sequential to justify the switch. I think someone got a 5% gain, and had to mess with the injector phase angle quite a bit to get there.
Sam, when you wire them up sequential, do you run the home or trigger signal wire to the CMP sensor signal? It says in the manual somewhere, but do you leave it set as motronic, or do you use the "mazda A" preset?
I actually misspoke when i grouped semi-sequential in. So I apologize... I was thinking of what most would call batch or grouped fire but is sometimes grouped in with semi-sequential (as cylinder can get fuel in a semi-sequential manner (as far as SEQUENCE, not method) under batch fire...).
here is a simple link that explains them, if semi-sequential, you are a little less efficient (and thus need extra fuel somtimes), and need a little more open tmie, but not by a ton, batch is when you get hurt the most due to the two injector "stops" so double the needed rest periods. And Maxx, you are right, there is not a huge differentiation between the two unless you optimize phase firing etc. Usually not a big deal for a lot of people.
http://www.motec.com/products/ecu/tutorial.htm
here is a simple link that explains them, if semi-sequential, you are a little less efficient (and thus need extra fuel somtimes), and need a little more open tmie, but not by a ton, batch is when you get hurt the most due to the two injector "stops" so double the needed rest periods. And Maxx, you are right, there is not a huge differentiation between the two unless you optimize phase firing etc. Usually not a big deal for a lot of people.
http://www.motec.com/products/ecu/tutorial.htm
Motronic. Page 151.
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You like to write page long dissertations to justify your reasoning. Save it for a PHD. I had to cut your dissertation short.
You ran a rising rate fuel pump, it bumps fuel pressure as MAP increases. Bumping up fuel pressure changes the equation.
The math isn't a shot in the dark. You are telling people to run the stock injectors to the very edge of their safe limits or even past the limits in those 2 quotes. Use this formula and plug in a BSFC at .45 and .60 to get your range. You can run it as conservative or not. Same result either way.
Brake specific should be .45 to .50 for naturally aspirated engines,
.55 TO .60 for supercharged engines,
and .60 to .65 for turbocharged engines. To convert cc / min to lbs. / hr. - Divide by 10.5
Plug in for 280cc or even 310cc injectors and see what you get.
I am informing people to correct information. I read this thread as it was stickied and there was slew of incorrect information.
Don't get mad I called you out and was right about it.
Maxx Mazda
Contributor
- :
- Stock P5
Thanks. Check your PM.
Only crap is what you post. (blah)
Get your facts straight and I don't have to call you out.
Have fun blowing people's motors up.
By the way, if you did this full time instead of a side job, you would know Unichip still makes the system, just the # of dealers that sell it are now limited.
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uh you just got owned. period. (stfu)
