maftpro is working

[drjonez]

yikes. rampant mis-info here....i'll reply sometime later today....

 

[toml]

Hah, that'd be appreciated drjonez.. just from following the last few posts its kinda lead me to believe that if I'm looking at a 500hp goal but wanting to retain 'stock driveability' then I should be looking into something different.

But I could be confused, mislead, totally ignorant, still waking up )) or whatever...

 

[yannis-supras]

yikes. rampant mis-info here....i'll reply sometime later today....

Hmm I don't know if all this is mis-info but I thought it was clarified here http://www.supramania.com/forums/showthread.php?t=6950&page=3 . From post #25 and on it was stated that maft pro deals with FCO and on post #28 it was mentioned that even a much desirable pressure adjustable fuel cut was a sw update away. That update has actually occured but without this function obviously...

 

[bigaaron]

Hmm I don't know if all this is mis-info but I thought it was clarified here http://www.supramania.com/forums/showthread.php?t=6950&page=3

Hopefully I am not part of the mis-information, i'm just trying to help. Honestly I don't have first hand tuning experience with the maft pro yet but I ran the maft for several years and did lots of tuning and adjusting of that.

 

[yannis-supras]

Oh no, Aaron I wasn't reffering to you at all. You see I think that Adam meant by "mis-information" the fact that maft pro resolves fuel cut. But if that's the case then it's getting complicared cause Adam verifyed that maft pro actually does that. But these are just my assumptions, come on Doc shed some light here :icon_bigg

 

[bigaaron]

yikes. rampant mis-info here....i'll reply sometime later today....

I quoted you by accident yannis, I was actually referring to the good doctor. Either way I would like to get the correct info so I can be a part of the solution rather then part of the problem, if that is the case. I know on the maft the fuel injector size affected the karman freq needed to make the right af ratio, and the smaller injector would need a higher karman freq which would cause an earlier fuel cut.

 

[yannis-supras]

Non the less it has been clearly stated on this thread that maft pro not only can deal with fuel cut by its own FCD but it would also offer the ability to set it to a higher pressure level. From people's experiences though this is not the case so far.

 

[elhsupra]

I am not familiar with the FCO, but isn't that the purpose of the "Freq out max" setting? To limit the maximum frequency(hz) that the ECU would see from what it thinks is the AFM. Unless fuel cut can also be triggered by oem sensors that the MAFTPro doesn't control.
Again I am not familiar with this since my application is N/A

 

[Adjuster]

Well, here is the rub.

The stock TCCS cut's the fuel at a hertz rate of about 1500hz. (This is the signal coming out of your Karmann meter, or AFM.)

Going to the lexus unit flows about 25% more air at the same freq. because the ID of the unit is larger. Going to 25% larger injectors results in about the right fuel tune on a stock TCCS with no other mods. (Thus the Lexus/550 mod was born.)

Tuning on the TCCS generally delt with PULLING fuel Hz rate that the TCCS "See's" via some kind of device. (SAFC, EMAN, MAFT Pro etc.) No changes to ignition retard could be made, and the Eman would allow timing advance, which is not much of a benefit unless you set the base timing low, and then added it all back where you wanted it...)

To keep the TCCS working even when the AFM is producing a signal in excess of 1500hz, some of the controlers allow the signal to be clamped off at a certain point. In the case of the Eman, that point is 1450hz. The TCCS never thinks the engine is pulling any more air than 1450hz when you clamp the signal, but since that's the case, it does not add any more fuel injection pulse width. (In theory, you could go 100+%, but more like 85% on Lucas type injectors is safer.)

So, going to larger injectors, you are pushing down the hz needed to fire those larger injectors to get the fuel needed to run the engine at lower speeds, and at lower boost levels, leaving more head room for the "85%" or so duty cycle/signal from the TCCS injector drivers to fuel your engine. The problem is sometimes at idle, you have to adjust the fuel even more to get it running right, and with larger injectors, that can be tricky.

I really don't want to go stand alone as the AEM EMS is too expensive, the Megasquirt looks like a royal PITA to wire up and tune, and I'm a cheap bastard who just want's to turn up the boost and not fry my motor. (Spell that rich fuel ratio's my friend.)

From what I can gather, this replaces the old VPC right? No more AFM, and the car is now speed density based. (The maft is just providing a nice hz signal for the TCCS to feed on.)
This does have the ability to clamp that hz rate at a value under 1500hz, so the TCCS does not fuel cut based on just hz rate alone. (Even though I've had trouble with FC, even with the rate clamped at 1450, it must have something to do with injector duty, or throttle position or some other load factor that the TCCS is reading and deciding my fun is over.)
This is why I'm looking at 720cc injectors. To gain more headroom on the TCCS. (And the Maft Pro can tune my idle so it's nice and smooth right after I set the idle fuel pressure so the Vf voltage is 2.5v?) I'm hoping that at that point, the Maft Pro would not need to do much, but that sounds like a hollow hope based on this feedback.

Will Neely just ran the VPC, the 720's and some fuel computer to get his running right? That's an affordable goal in my opinon. The AF tune and other stuff would just be icing on the cake if my fuel economy improved as a result of this piggyback. (I can buy LOTS of fuel with the difference in the cost between a maft pro, and a simple AEM EMS and some tuning time on the dyno, figure nearly 3k for the AEM tuned right, and under 700.00 for the Maft Pro...) Ok, 2300.00 buys me quite a bit of gas.

The 720's are not fixed in stone yet either. I could go 680 right? But I figure if the 720's will work, why not have the larger ones since last time I thought the 550's would be all I'd ever need.... (Ok, so 1000cc injectors are not on my plate, or budget.)

My wife is tired of this money pit car, and I'm tired of screwing with it actually, so this is my last modification binge. (Turbo/manifold/fuel computer/etc.) I really just want somthing that will supply fuel for a T70 Ebay turbo and not cost an arm and a leg to run around in. Heck, anything over 450, 500rwhp is mostly tire smoke anyway, but the idea of getting rid of the AFM with the current "VPC" setup appeals to me. Larger injectors that leave more headroom and less chance of FC appeals to me. Endless tuning and datalogging and changeing this and that all the time does not appeal to me at all.. LOL

 

[drjonez]

well, here it is...let the flames begin!

Hey folks,
I have read that some of you are having issues with the latest version of TunerPro RT. I little while ago I helped another board member with a similar issue. Here is a link on the FullThrottle site which talks about the same problem. In my reply to that post I wrote down the steps and attached a file that should get you up and running with the TunerPro RT program....Enjoy!

http://www.fullthrottletech.com/showthread.php?p=9674#post9674

Good info….

For those of you having stumbling issues when hitting the gas, I changed my Throttle body size to 15 and it made a big differance. I also had better luck messing with the MAP enrich rather than the TPS enrich. I set my TPS enrich to 0 and the mapenrich is at .21 (if memory serves me right).

Stumbling issues are due to the nature of the speed/density conversion. Settings will be different for every car, you’ll need to play with the settings to make it work correctly for your car.

I have asked the same question in the past numerous times, especially prior to buying the Maft pro but the answer back then was always afirmative. That was the main reason that I bought the Maft Pro for; to overcome FCO...

Forgive me for phrasing my response to adjuster in such a manner.

As already stated, there is more that goes into FCO calculation than just mass-flow. RPM, TPS, coolant temp, intake temp all play a role. Finding the balance of settings to completely prevent FCO is quite a trick.

Yes, the MAFT pro can be updated with code to account for all those settings. We’re looking into it…

So I Suppose Fcd Is Needed?

Maybe? I don’t think so…

The best thing to do is get your car tuned and see where you’re at. Are you still getting a load FCO? Are you getting any FCO? Sort that out first, before you panic….

If you have big enough injectors for the power you are making you will not have any fuel cut issues.

Misinfo #1.

Injector size has NOTHING to do w/FCO. Yes, it’s call fuel cut off….but that’s just because fuel is being cut off. Injector size, fuel pump size, etc. will have NO affect on the FCO point.

Yes, you can “fool” the ECU by running huge injectors or high fuel press and removing a lot of signal via an AFM scaling device. Is this a good idea? Probably not as large AFM corrections = large amounts of timing advance.

I am running 720's also.

Contrary to popular belief I have been driving the car with the stock ECU for about 3000 miles. The only issues I ahve is it goes pig rich at WOT and my BOV vents to atmosphere so it is also rich between shifts. Closed loop operation always stays very close to 14.7.

I dont see any reason to use the MAFT Pro to tune for drivability. I set my FPR to the lowest it could go and still idle good (which was like 28psi with vac connected) and hopefully that will get me in tunable range at WOT.

Yup, no surprises there. Unfortunately, the ECU is trying it’s hardest to yank as much fuel as possible. Tuning to balance out Vf will be needed….

No, no I still haven't fitted mine, my engine is nor even running yet :icon_bigg I hopw I will be ready to check it out in a month or so. I'm just checking everyone else's experiences so far so that I will be prepared.
So you're saying that with that size of injectors FCO shouldn't be a problem then?

See my above post re: FCO vs. inj. size.

Hah, that'd be appreciated drjonez.. just from following the last few posts its kinda lead me to believe that if I'm looking at a 500hp goal but wanting to retain 'stock driveability' then I should be looking into something different.

But I could be confused, mislead, totally ignorant, still waking up )) or whatever...

First off, you need to note what power level is that- 500 crank or 500 rwhp. My intent in all my comments re: standalone is simple- there are a myriad of ways to do it, but there is always a BEST way to do it. Think about it- mid-500srwhp is almost 3X the stock output….you can’t possibly expect the stock ECU + a piggyback to be able to cope with that much of a difference.

Driveability is ALL a function of how much time you spend tuning….with ANY set up. You cannot expect to buy a device, plug it in and have the car drive like stock. It takes TIME of changing varied settings, logging runs and watching your gauges (WB, EGT, etc.)

… on post #28 it was mentioned that even a much desirable pressure adjustable fuel cut was a sw update away. That update has actually occured but without this function obviously...

That is true, it IS just a SW update away….obviously there is A LOT going on for development and new SW is always being developed….

…I know on the maft the fuel injector size affected the karman freq needed to make the right af ratio, and the smaller injector would need a higher karman freq which would cause an earlier fuel cut.

As with any device that offers “injector correction”, it’s merely a global AFM scale….in which case increasing inj. size decreases the mass flow input to the ECU. Useful to a point, just keep in mind the inverse relationship between mass-flow and timing ….less mass-flow = MORE timing.

Non the less it has been clearly stated on this thread that maft pro not only can deal with fuel cut by its own FCD but it would also offer the ability to set it to a higher pressure level. From people's experiences though this is not the case so far.

Where? Please show me an example of someone who has followed all the steps, taken the time to tune and STILL has FCO. Examples of people who are confused and just want a simple fix need not apply…

The issue is multi-faceted- the above listed parameters that affect FCO and then the end user. See my above comments re: the PROPER way to do things….

I am not familiar with the FCO, but isn't that the purpose of the "Freq out max" setting? To limit the maximum frequency(hz) that the ECU would see from what it thinks is the AFM. Unless fuel cut can also be triggered by oem sensors that the MAFTPro doesn't control.
Again I am not familiar with this since my application is N/A

Yup, Foutmax is there for that purpose- to clamp the MAFT pro’s output to the ECU’s input.

See my above comments re: other parameters that has an affect on FCO.

Well, here is the rub.

The stock TCCS cut's the fuel at a hertz rate of about 1500hz. (This is the signal coming out of your Karmann meter, or AFM.)

Give or take, yup.

Going to the lexus unit flows about 25% more air at the same freq. because the ID of the unit is larger. Going to 25% larger injectors results in about the right fuel tune on a stock TCCS with no other mods. (Thus the Lexus/550 mod was born.)

Don’t forget about the much larger bypass chamber…

Tuning on the TCCS generally delt with PULLING fuel Hz rate that the TCCS "See's" via some kind of device. (SAFC, EMAN, MAFT Pro etc.) No changes to ignition retard could be made, and the Eman would allow timing advance, which is not much of a benefit unless you set the base timing low, and then added it all back where you wanted it...)

Scaling the AFM input to the ECU….if anything you end up with more advance….

Yup, the eman could retard, you just needed the Igf simulator.

To keep the TCCS working even when the AFM is producing a signal in excess of 1500hz, some of the controlers allow the signal to be clamped off at a certain point. In the case of the Eman, that point is 1450hz. The TCCS never thinks the engine is pulling any more air than 1450hz when you clamp the signal, but since that's the case, it does not add any more fuel injection pulse width. (In theory, you could go 100+%, but more like 85% on Lucas type injectors is safer.)

And as previously stated, at 1450 or so you’re still near 85-100% duty….

So, going to larger injectors, you are pushing down the hz needed to fire those larger injectors to get the fuel needed to run the engine at lower speeds, and at lower boost levels, leaving more head room for the "85%" or so duty cycle/signal from the TCCS injector drivers to fuel your engine. The problem is sometimes at idle, you have to adjust the fuel even more to get it running right, and with larger injectors, that can be tricky.

I assume you mean you install larger injectors and then further AFM scaling (reduction). See my previous comments re: mass-flow vs. timing….

I really don't want to go stand alone as the AEM EMS is too expensive, the Megasquirt looks like a royal PITA to wire up and tune, and I'm a cheap bastard who just want's to turn up the boost and not fry my motor. (Spell that rich fuel ratio's my friend.)

Honestly, this is reasoning I don’t understand- you have how much $$ invested in your stroker/coated engine? How much invested in your turbo setup? Yet you won’t invest $1.5k or so in proper engine management…that’s like building a huge mansion and using milkcrates for furniture….

From what I can gather, this replaces the old VPC right? No more AFM, and the car is now speed density based. (The maft is just providing a nice hz signal for the TCCS to feed on.)

Yup, the MAFT pro performs calculations to convert from speed/density to the proper mass-flow output to the ECU….and it even has a clean signal!

This does have the ability to clamp that hz rate at a value under 1500hz, so the TCCS does not fuel cut based on just hz rate alone. (Even though I've had trouble with FC, even with the rate clamped at 1450, it must have something to do with injector duty, or throttle position or some other load factor that the TCCS is reading and deciding my fun is over.)

Yup, the MAFT pro can do that. Yup, there’s other stuff involved in the FCO calculation…see above.

This is why I'm looking at 720cc injectors. To gain more headroom on the TCCS. (And the Maft Pro can tune my idle so it's nice and smooth right after I set the idle fuel pressure so the Vf voltage is 2.5v?) I'm hoping that at that point, the Maft Pro would not need to do much, but that sounds like a hollow hope based on this feedback.

Not sure how that’s hollow….yes, it’s possible do this as stated above. My only reservation is the timing issues….as stated above.

Will Neely just ran the VPC, the 720's and some fuel computer to get his running right? That's an affordable goal in my opinon. The AF tune and other stuff would just be icing on the cake if my fuel economy improved as a result of this piggyback. (I can buy LOTS of fuel with the difference in the cost between a maft pro, and a simple AEM EMS and some tuning time on the dyno, figure nearly 3k for the AEM tuned right, and under 700.00 for the Maft Pro...) Ok, 2300.00 buys me quite a bit of gas.

Sure, will did it…..he used a SAFC. Again, was it the best way? No sir.

$3k for an AEM EMS? Sounds a bit high to me…what about dyno time for the MAFT pro?

The 720's are not fixed in stone yet either. I could go 680 right? But I figure if the 720's will work, why not have the larger ones since last time I thought the 550's would be all I'd ever need.... (Ok, so 1000cc injectors are not on my plate, or budget.)

Inj. size should be based on ultimate power goals.

My wife is tired of this money pit car, and I'm tired of screwing with it actually, so this is my last modification binge. (Turbo/manifold/fuel computer/etc.) I really just want somthing that will supply fuel for a T70 Ebay turbo and not cost an arm and a leg to run around in. Heck, anything over 450, 500rwhp is mostly tire smoke anyway, but the idea of getting rid of the AFM with the current "VPC" setup appeals to me. Larger injectors that leave more headroom and less chance of FC appeals to me. Endless tuning and datalogging and changeing this and that all the time does not appeal to me at all.. LOL

See above. In order to get it to “just work” you have to spend the time on the front end tuning….there is no set up that will just plug n go.

 

[mixmastermatt]

I see a lot of people talking about trying to tune to compensate for Vf correction and maintian the AFR that they want during closed loop. Why not get rid of the Vf correction all together? Removing O2 sensor feedback will force full time open loop, even at idle. My experience with this has proven fairly successful. Using my SAFC2, I was able to tune for a simulated "closed loop" @ 15:1afr for low load and cruising conditions. Under load, the transition to a 11.9:1afr was clean without the typical spiking that is usually experienced. Coming back off throttle, it would transition back to the "closed loop" smoothly. I used a GM 2bar map sensor as the "throttle" input to the safc to determine which map to use. I know, most of you will say the Vf correction is neccessary to correct for any fuel delivery system issues. If you have upgraded the pump, lines, fpr and injectors, and you monitor fuel pressure, then you don't need the Vf correction. Especially with the MAFTpro, enabling the AFR tracking will do the same thing, without fighting the Vf. I'll try to get some screen shots from my LM-1 and show you what I mean in the logs.

 

[drjonez]

I see a lot of people talking about trying to tune to compensate for Vf correction and maintian the AFR that they want during closed loop. Why not get rid of the Vf correction all together? Removing O2 sensor feedback will force full time open loop, even at idle. My experience with this has proven fairly successful. Using my SAFC2, I was able to tune for a simulated "closed loop" @ 15:1afr for low load and cruising conditions. Under load, the transition to a 11.9:1afr was clean without the typical spiking that is usually experienced. Coming back off throttle, it would transition back to the "closed loop" smoothly. I used a GM 2bar map sensor as the "throttle" input to the safc to determine which map to use. I know, most of you will say the Vf correction is neccessary to correct for any fuel delivery system issues. If you have upgraded the pump, lines, fpr and injectors, and you monitor fuel pressure, then you don't need the Vf correction. Especially with the MAFTpro, enabling the AFR tracking will do the same thing, without fighting the Vf. I'll try to get some screen shots from my LM-1 and show you what I mean in the logs.

there really isn't a "Vf correction", just the Vf output indicating what the ECU is doing w/the fueling.

while your idea is a good one, the big unknown is what does the ECU do w/o any O2 feedback? what fuel/timing table does it leave you on? what about long term fuel trim? a safe guess is it puts you in one of the "limp" tables- i.e. real rich and not a lot of advance. it would be a good question to ask reg up in CAN....he should know.

 

[mixmastermatt]

I know its not a limp table. As for long term trim, if you reset the ECU prior to, the long term and short term trims will be 0. I think it uses the same timing and fuel table as what it would normally use in open loop, with no trims applied(if the ECU had been reset). At idle and low load conditions, with no correction from the safc, it sits at about 10:1afr.

 

[drjonez]

I know its not a limp table. As for long term trim, if you reset the ECU prior to, the long term and short term trims will be 0. I think it uses the same timing and fuel table as what it would normally use in open loop, with no trims applied(if the ECU had been reset). At idle and low load conditions, with no correction from the safc, it sits at about 10:1afr.

what's Vf w/o the O2 sensor connected?

 

[bigaaron]

Originally Posted by bigaaron
If you have big enough injectors for the power you are making you will not have any fuel cut issues.

Misinfo #1.
Injector size has NOTHING to do w/FCO. Yes, it’s call fuel cut off….but that’s just because fuel is being cut off. Injector size, fuel pump size, etc. will have NO affect on the FCO point.

Originally Posted by bigaaron
…I know on the maft the fuel injector size affected the karman freq needed to make the right af ratio, and the smaller injector would need a higher karman freq which would cause an earlier fuel cut.

Yes, you can “fool” the ECU by running huge injectors or high fuel press and removing a lot of signal via an AFM scaling device. Is this a good idea? Probably not as large AFM corrections = large amounts of timing advance.

See, this is where I fail to understand you. You say I am wrong, but then you basically agree if I word the same thing differently.

Here is an example:
You have 440 cc injectors and you want to make xxx hp and to do that you need to have xx psi of boost. You have a afpr also and it's maxed out. To get a safe a/f ratio at that point you will need a specific karman freq to make the ecu run the injectors at the proper duty cycle to get to the proper a/f ratio. You are already at 1500 hz and still at 13.5/1 at xx psi and xxx hp, what kind of "tuning" are you talking about that will fix that? So some of the unsuspecting people hear about a fcd and figure they will set that at 1450hz and they will not have fuel cut. Right, but they will also have a melted piston running 15/1 under boost. You make it sound like no one runs injectors that are too small and it is always just a tuning issue. Now I do understand that you obviously don't want a 1000cc injector to run 10 psi, you need to match the injector to the hp expected from the engine, otherwise the timing will be off.

Injector size directly affects the karman freq you will need to have output from the maft to get the proper tuning, and you have said the karman freq is the number one factor in fuel cut. I didn't say to run a monster injector and scale it back to 500hz, I said "if you have big enough injectors for the power you are making you will not have any fuel cut issues. I think we are arguing over semantics instead of agreeing about the main point. I guess I should change it to:
"if you have the right size injectors for the power you are making, and the tuning is done properly, you will not have any fuel cut issues.
You (on the other hand) shouldn't imply that the tuning is the only thing that fixes a "fuel cut problem"

 

[drjonez]

See, this is where I fail to understand you. You say I am wrong, but then you basically agree if I word the same thing differently.

not sure where the hard part is- larger fuel inj. ALONE will NOT affect FCO. NO hard fuel part (pump, inj., line, tube, etc.) will have ANY bearings on FCO.

you need to think about who will be reading this and be as clear as possible....

Here is an example:
You have 440 cc injectors and you want to make xxx hp and to do that you need to have xx psi of boost. You have a afpr also and it's maxxed out. To get a safe a/f ratio at that point you will need a specific karman freq to make the ecu run the injectors at the proper duty cycle to get to the proper a/f ratio. You are already at 1500 hz and still at 13.5/1 at xx psi and xxx hp, what kind of "tuning" are you talking about that will fix that? So some of the unsuspecting people hear about a fcd and figure they will set that at 1450hz and they will not have fuel cut. Right, but they will also have a melted piston running 15/1 under boost. You make it sound like no one runs injectors that are too small and it is always just a tuning issue. Now I do understand that you obviously don't want a 1000cc injector to run 10 psi, you need to match the injector to the hp expected from the engine, otherwise the timing will be off.

Injector size directly affects the karman freq you will need to have output from the maft to get the proper tuning, and you have said the karman freq is the number one factor in fuel cut.

i can't follow that too well....the thing you're missing is that for a given mass-flow rate the ECU will set XX inj. duty. typically around the FCO point (1500 Hz) the ECU is running near max inj. duty.

inj. size has nothing to do w/AFM output....until you start messing w/the AFM output via an AFM scaling device (SAFR, SAFC, MAFT, etc.). the AFM will continue to output XXXX Hz for a given mass-flow rate....regardless of whether or not there are 200cc inj or 1000cc inj installed.....airflow = airflow.

 

[bigaaron]

not sure where the hard part is- larger fuel inj. ALONE will NOT affect FCO. NO hard fuel part (pump, inj., line, tube, etc.) will have ANY bearings on FCO.

you need to think about who will be reading this and be as clear as possible....



i can't follow that too well....the thing you're missing is that for a given mass-flow rate the ECU will set XX inj. duty. typically around the FCO point (1500 Hz) the ECU is running near max inj. duty.

inj. size has nothing to do w/AFM output....until you start messing w/the AFM output via an AFM scaling device (SAFR, SAFC, MAFT, etc.). the AFM will continue to output XXXX Hz for a given mass-flow rate....regardless of whether or not there are 200cc inj or 1000cc inj installed.....airflow = airflow.

You answered before I was done editing my post.

WE ARE TALKING ABOUT A AFM SCALING DEVICE. its a MAFT we are talking about in this whole thread. Everything I said is with reguards to a maft.

 

[drjonez]

honestly, i think we've reached the point if diminishing returns in this thread. i cannot keep fielding tons of questions that are approximately the same here or general questions....the original intent of this thread was for discussion of the MAFT pro. i will try to continue to answer MAFT pro related questions, but i will let the rest slide.

 

[drjonez]

You answered before I was done editing my post.

WE ARE TALKING ABOUT A AFM SCALING DEVICE. its a MAFT we are talking about in this whole thread. Everything I said is with reguards to a maft.

wonderful. my statement about inj. size vs. mass flow is NOT about an AFM scaling device, read post 676.

 

[bigaaron]

honestly, i think we've reached the point if diminishing returns in this thread. i cannot keep fielding tons of questions that are approximately the same here or general questions....the original intent of this thread was for discussion of the MAFT pro. i will try to continue to answer MAFT pro related questions, but i will let the rest slide.

I was thinking the same thing just now, I am coming from the point of warning people not to run a maft to get rid of their fuel cut when their main issue might be that they need a bigger injector. I know that is not always the case.