Supercharger and Fuel Map Discussion

[Romer]

Sumotoy, I understand thats your opinion and you have gobs of experience, but I think your wrong on the closed loop stuff. Did you read the sheet from Toyota?

I would hate for this conversation to go down a dirt road because of one persons opinion.

Where do you get your numbers and %'s and "by your measurements" above. If it's not a source specifically on this engine and setup, it is worthless information. Please define.

You can not take what you know about Audi's or other vehicles and assume that this setup is the same.

 

[sleeoffroad]

ST, Can we please agree to disagree that you think a FPR and bigger injectors is the only way to do it, and I say that a piggyback with extra injectors is a much better and easier way to do it.

I would rather be able to tune using numbers I plug into a computer vs swapping hardware parts until I get it right.

 

[sleeoffroad]

Other manufacturers fuel maps are not proprietary and can be modified (re-programmed). Toyota's can not be modified, as far as we know. Think of the fuel map as a duty cycle time for off/on.

Any chip program can be modified, they are all proprietary. It's a lot of work, but it can be done. The fuel map is usually 3D, i.e. it's a fuel map and a timing map.

Show me someome that has tweaked the Toyota ECU. I know anything is possible, just not sure we have enough $'s to do it.

Now adding a FPR or better injectors will not help in the above scenario during closed loop operation as the Toyota computer will adjust the duty cycle to be back with what it is now using the sensors.

NO. You have increased the airflow, so you have increased the need for fuel. You can easily put in bigger injectors and/or FPR and the computer will operate just fine. The trick is making sure you don't go beyond the capabilities of the electronics, while still supplying enough fuel for the demands of the engine. If what you say is true, you should have a fuel code with the supra fuel pump.

Why is it an automatic NO? The truck is using 02 sensor feedback to adjust fuel trim. If the stock pump and injectors can keep up, even under boost, then there is no need for it in closed loop.

If you put to big of an injector in the truck can also trip a code if the fuel trim can not back the extra fuel out. This is probably what you mean with trick.

When Christo adds additional injectors in his turbo set-up, he has a piggy back computer controlling them. He uses his fuel mixture gauge (AWO) and adjusts via his laptop while driving to tweak it. This only controls the additional two injectors.

I don't think you need them, but they will work. At 15% DC, a bigger injector would probably work, as would better, just a single injector running 30% DC.

ST, the above is a prime example of why people get pissed at your posts. Just because you think you don't need them does not make it a bad thing to do. You automtically disregard anyone elses experience in favor of your past experience.

I never post btdt plus 5 year of experience etc etc. However we do have a little more experience in tuning turbo's on the 1FZFE than you. I don't have any on the Audi's though. I can just tell you that tuning a 1FZFE is way easier with a piggyback computer and extra injectors that swapping parts until we have it right.

Open loop is the operation where a different Regulator or injectors would impact operation. It is unclear if a SC engine in Open loop is running a little lean, a little rich or "just right".

Not true, if you have boost below WOT, you have boost under closed loop operation. The SC engine is running a 'little lean' by my measures, but hardly dangerously so.

Please show me what part of the statement that Romer made is not true? Your reply on the quote is not even relevant to that quote?

 

[landtank]

I spent the better part of the day doing research.

Our trucks running a stock injector with a SC puts the duty cycle at 85%. this is a little high as most put the exceptable max limit at 80%.

The injectors that I bought are from a 1986.5-1992 Supra. They are 380cc/36# injectors and if installed on the SC truck they would work in the 71% range.

Our stock MAF is calibrated for 30lb injectors.

If I were to install the 36# Supra injectors I would need to replace the stock MAF with one tuned to the 36# injectors. If I didn't the the truck would run rich during the open loop cycle. This is do to the fact that that the ECU will pulse the injectors based on the MAF report on air at the 30# rate.

Our MAF is a 5 wire connection. Some hot wire MAFs are 4 wire connections. Either will work as the 5 wire has one dummy in there from what I can tell. I've lost track of my EWD book so if some one could post up the wiring to the MAF I could check it out.

Right now the best looking candidate is the MAF for a Ford Lightening. It uses a 90mm MAF and there are companies that will tune them for the proper pound injectors. This is a supercharged truck so a stock unit might also work if the proper sized injectors can be found. Most of the Ford MAFs use a flange type base which looks compatable to the air cleaners on the pre 95 trucks. That would be nice otherwise there are adapters available, but I'd prefer to avoid that.

It's possible to stay in the Toyata family for the MAF. I just need to find a hot wire MAF on a car with the larger injectors. I had found a site yesturday that listed the injector sizes for the Toyotas but didn't save it and can't find it for the life of me today.

This is a very common upgrade. Lexus owners use both the MAF and injectors form a Supra to gain performance on their LS400s anjd I found a guy who used a Lexus MAF to run high lb injectors on his Supra.

It's basically finding a matched set that will physically fit the engine in the 440cc/42lb injector size.b These would put the duty cycle at around 61%

Dan's busy right now but there is an application within Toyota that might work.


disclaimer: all calculations were using RC Engineering formulars

 

[SUMOTOY]

Sumotoy, I understand thats your opinion and you have gobs of experience, but I think your wrong on the closed loop stuff. Did you read the sheet from Toyota?

Read it. Very basic, and I think you misinterpreted what it says. Specifically Page 5 PP1 and PP2

All fuel systems with 02 are defined this way. Remember, getting 14.7:1 (1.00lambda) is only a moment in time. Load determines how much of that moment you really see.

I would hate for this conversation to go down a dirt road because of one persons opinion.

Again, fuel injection isn't opinion, exactly what the box does is a best guess, but they all strive for the same thing.

Where do you get your numbers and %'s and "by your measurements" above. If it's not a source specifically on this engine and setup, it is worthless information. Please define.

You can not take what you know about Audi's or other vehicles and assume that this setup is the same.

EFI is EFI, this defines OBDII. Remember, the computer is just a calculator. It doesn't know what you did, it only knows what timing and fuel point to use on a matrix. Some systems have more inputs or are more sophisticated, but they all do the same thing in terms of operation of the fuel injectors.

Regarding percentages, the computer in open loop mode goes to a set of tables, again these are calculated tables, they aren't picked from the inputs anymore. Think of WOT as WFO (wide f'n open), as in dump fuel to estimate .86 lamda. Up to the wide band O2 introduction, that's how every carbeurator, CIS and EFI system works.

I assume this is the same, because this is how EFI works. 80's are not special cases.

Again, if you want to claim so, it's certainly not in the document you referenced.

ST

 

[Romer]

See thats the problem with your posts. You don't know for sure so you ASSUME based on your years of documented experiance. ASSUMING gets people into trouble. I am an engineer and know better than to assume.

Christo knows a lot more about this stuff then you do relative to this engine, plain and simple fact. He has demonstrated his knowledge with accomplishments. I have not seen one accomplishment relative to this engine from you.

Your a smart guy with a lot to contribute, stop posting like your THE EXPERT, your not. This is my thread so I am talking like a mudder and not as a moderator (disclaimer). You need to answer questions straight on with specifics, half the time your answers are like a polititians, you dance around and never take the question head on. This is why a lot of folks have issues with your posts.

Unless you have specific Toyota Data or can be clear and concise, stay out of my thread. It was a great discussion before.

 

[SUMOTOY]

ST, Can we please agree to disagree that you think a FPR and bigger injectors is the only way to do it, and I say that a piggyback with extra injectors is a much better and easier way to do it.

I would rather be able to tune using numbers I plug into a computer vs swapping hardware parts until I get it right.

You can plug them into a spreadsheet and get pretty darn close, that's why I use them. A piggy back can work, but Christo, a 15% DC on an injector is too low, the normal operating range is 20-80%. Above that it goes semistatic, below that you don't get good fuel atomization. That's pretty well documented.

I look at fuel as just science. An adjustable fuel pressure regulator (that BEGI is really nice to work with) with the proper size injectors really negates the need for piggy back. You can use the, I have, but not since my last CIS tweeking days. In EFI, it's redundant, you already have a electronic fuel injection system, why add another? Because it's easier than learning to size fuel injectors and fuel pressures? That's where we disagree. I believe you think you have more adjustability with a piggy back, I believe you have almost infinite adustability with the stock EFI. The question is: What are you looking for it to do? If both of us can answer the question, why add another system into the mix.

I like computers with knock sensor input that have been designed for the application. I rarely find fuel the reason to change that. I can find a lot of other reasons to change to standalone. I find no reason to piggy back either the OBDI or especially OBDII fuel systems.

ST

 

[SUMOTOY]

I spent the better part of the day doing research.

Our trucks running a stock injector with a SC puts the duty cycle at 85%. this is a little high as most put the exceptable max limit at 80%.

The injectors that I bought are from a 1986.5-1992 Supra. They are 380cc/36# injectors and if installed on the SC truck they would work in the 71% range.

Our stock MAF is calibrated for 30lb injectors.

If I were to install the 36# Supra injectors I would need to replace the stock MAF with one tuned to the 36# injectors. If I didn't the the truck would run rich during the open loop cycle. This is do to the fact that that the ECU will pulse the injectors based on the MAF report on air at the 30# rate.

Our MAF is a 5 wire connection. Some hot wire MAFs are 4 wire connections. Either will work as the 5 wire has one dummy in there from what I can tell. I've lost track of my EWD book so if some one could post up the wiring to the MAF I could check it out.

Right now the best looking candidate is the MAF for a Ford Lightening. It uses a 90mm MAF and there are companies that will tune them for the proper pound injectors. This is a supercharged truck so a stock unit might also work if the proper sized injectors can be found. Most of the Ford MAFs use a flange type base which looks compatable to the air cleaners on the pre 95 trucks. That would be nice otherwise there are adapters available, but I'd prefer to avoid that.

It's possible to stay in the Toyata family for the MAF. I just need to find a hot wire MAF on a car with the larger injectors. I had found a site yesturday that listed the injector sizes for the Toyotas but didn't save it and can't find it for the life of me today.

This is a very common upgrade. Lexus owners use both the MAF and injectors form a Supra to gain performance on their LS400s anjd I found a guy who used a Lexus MAF to run high lb injectors on his Supra.

It's basically finding a matched set that will physically fit the engine in the 440cc/42lb injector size.b These would put the duty cycle at around 61%

Dan's busy right now but there is an application within Toyota that might work.


disclaimer: all calculations were using RC Engineering formulars

You don't need to do this! MAF on OBDII will use long term fuel trim to modify the baseline injector DC. Rick, before you spend a penny on the MAF, try a different injector with the stock MAF. BTDT many times.

I used RCE site and got 328HP at 80% DC at 43psi (a bit on the high side in terms of HP, but not that far off). Why exactly are you looking for bigger injectors? Try doing this with boost, and use a rising rate fuel pressure regulator. What happens to the 'effective' fuel injector size?

I'll put down the first punch. Leave the MAF out of this for now, if it can measure the air, leave it alone. IME (more than doubling HP), a MAF needs replacing if it codes, is a restriction to airflow, or can't measure the airflow going thru it. You have none of those issues.

ST

 

[SUMOTOY]

See thats the problem with your posts. You don't know for sure so you ASSUME based on your years of documented experiance. ASSUMING gets people into trouble. I am an engineer and know better than to assume.

I assume nothing. I KNOW that OBD I and OBDII compliant EFI all works the same way.

Christo knows a lot more about this stuff then you do relative to this engine, plain and simple fact. He has demonstrated his knowledge with accomplishments. I have not seen one accomplishment relative to this engine from you.

Means more to you than me. I only look at a fuel system, and the documentation you put forth of it, and say it's exactly as I have learned EFI in my 20 years with it. In fact, get Probst book, if you think toyotas is different, some of the tech sheet you published is almost verbatum.

Your a smart guy with a lot to contribute, stop posting like your THE EXPERT, your not. This is my thread so I am talking like a mudder and not as a moderator (disclaimer). You need to answer questions straight on with specifics, half the time your answers are like a polititians, you dance around and never take the question head on. This is why a lot of folks have issues with your posts.

Unless you have specific Toyota Data or can be clear and concise, stay out of my thread. It was a great discussion before.

Yikes! Ken, I am an educator by nature. I understand HOW fuel systems work. I have now seen a supra fuel pump, piggy back injectors, and a larger MAF. 2 won't do what has been proposed, and 1 is just unnecessary.

The problem here, is that most want to jump to the FIX. Without understanding how it works, how are you going to FIX anything? I'm looking for a baseline in terms of understanding how a fuel system works, then I'm happy to HELP folks work towards the solutions.

To tell me that I come off as the expert isn't right. I'm not an expert, I have a lot of fuel system experience. What I rarely do, is just give the easy answer. In fuel, turbos etc, it's the homework that earns the answers. What nobody wants to do is blow up a motor, or spend oodles of dollars learning that what they did was a waste. THERE I am an expert!

I look at fuel simply as this. Find out what's happening in your fuel system by calculating what you think it is you need, testing (WBO2 and/or fuel pressure and/or gas analyzer), and earn your answers. I can put down a lot of the answers here. That's never been my modus. I can HELP in a tech discussion, and put up a lot of experience and theory to HELP that discussion lead to understanding of various technical systems.

I had 3 days away from the thread, as I drove my SC truck and loaded tandem trailer to Chesapeak and back along the hills of route 68. I'm quite pleased that my truck didn't blow up, didn't run so lean with a 120k stock fuel pump climbing the hills at 6.5psi that it snapped a rod. I'm pleased that my understanding and testing of the 80 fuel system did not change what I understood to be in the hardware and software profiles of my toyota truck.

I appreciate your caution, I urge you to take the same approach to allowing an in depth technical discussion to go in depth.

I'm game and you started it.

ST

 

[Romer]

You havn't been paying attention again, If your an educator you have a lot learn about educating. As I have told you many times, you don't undertsand your audience, you don't try and understand what they are saying and you jump right too it and start spouting off all your experiance (see 20 years above, a few days ago it was only 15) and this is the way it is. I get more PM's about you because people don't know what the fawk your talking about that they are afraid to enter the discussion. Discussions are two way. Looking back to your threads, you qoute someone and tell them how it is rather than discussing.

Geez, another perfectly good thread ruined. We were trying to discuss how the 1FZE fuel system works and figure it out and Lantank was collecting data from similar components so we could discuss data and not my 40 years of experiance!

 

[sleeoffroad]

I look at fuel as just science. An adjustable fuel pressure regulator (that BEGI is really nice to work with) with the proper size injectors really negates the need for piggy back.

Until you have done it with a turbo system comparable to the AVO unit we use, please don't tell me it does not work and it is uncessary. Why? I have a complete fuel map to work with, especially in open loop at the top end. What do you have in terms of tunability with a fuel regulator and bigger injectors?

I am not saying that a piggy back is the answer for a SC charged truck with no intercooler. This discussion came from the people wanting to do turbo's.

As for atomization, yes, we could have disconnected 1 injector and just tuned it for one, which would have put us into the higher DC range. Something we would like to try. However we are also installing a system designed by a Turbo company (pretty sure orders of magnitute more experience based on your 15/20 years experience) and I have to trust what they gave me is the way to go.

If you doubt what they do, look up http://www.avoturbo.com/

The 1FZFE kit is not the only one they do.


> In EFI, it's redundant, you already have a electronic fuel injection system, why add another?

Why do they exist? Are all the companies that make them dumb?


> Because it's easier than learning to size fuel njectors and fuel pressures? That's where we disagree. I believe you think you have more adjustability with a piggy back, I believe you have almost infinite adustability with the stock EFI.

As do you with the piggy back system. Just because you don't like it, doesn't mean it does not work.

The question is: What are you looking for it to do?

Optimum performance and make sure we do not blow a motor up.

If both of us can answer the question, why add another system into the mix.

I am of the opinion that you will not be able to get optimum results with the turbo using a regulator and extra injectors. I have seen the tuning maps for the 80 with the turbo we did, you have not.