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MS3Pro PnP Build Thread

3120 Views 97 Replies 4 Participants Last post by  eschaider
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Hello everyone,

First off, this thread is for a 96-98 GT and not Terminator Cobra. This sub-forum has a lot more activity so I was asked to create my build thread here.

I had an issue with my car, most likely due to weak ignition. I spoked to Ed and we agreed that it would be best to upgrate to a MS3 ECU and IGN-4 coil packs to replace the OEM stuff. Of course, the MS3 opens up a world of possibilities and I want all the bells and whistles, one step at the time.

Here it is
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The first thing I did after plugging it in, is upgrade the firmware to 1.5.2. I don't know why it shipped with 1.5.1 since the newer version is older than the release date of the ECU, but it was straightforward. I noticed the radiator fan would come up as soon as I turn the key on. It was not like that with the OEM ECU. It did a lot for debugging, the guys at DIYAutoTune were REALLY helpful and they replied pretty much instantly. Turns out I had a dead transistor and had to ship the ECU back for repair. They repaired it the next day they received it, but the whole round-trip took 3 weeks because I'm from Canada.

Meanwhile, I had the time to install my Spartan 3 wideband controller from 14point7. Allan (the owner of 14point7) was also helpful and answered all my questions. I got two wideband and two controllers, so one for each side. They are wired to the MS3 via CAN BUS. The instructions on how to set up all this were very good. In fact, everything worked on the first try! I emailed Allan to congrats him on the product and instructions and somehow turned a bad day for him into a good day. It's nice to sometime contact the people behind a company to tell them when we are happy, not only when things go bad. I also set up the controller to start heating the sensors when the engine has been running for about a minute. This is supposed to improve the life of the sensor because they won't be hit with cold condensation while they are hot.
Here is the controllers, next to the J&S Vampire. All this is under the passenger seat
Bag Luggage and bags Electrical wiring Gas Automotive lighting



Next was tuning the idle. I managed to solve an issue I had with the OEM ECU since I converted the car to an automatic transmission (2016). When it's cold, and I get it in gear, it would stall. I searched for years to open up some more of the IAC when in gear with the OEM computer but it wasn't possible. Turns out the solution was so much easier. I had 14* timing at idle. I bumped it to 18* and voila, no more stalling when cold.
Another thing that helped to stabilize the idle a lot is getting the injector dead time correct. I had not touched this configuration from the base tune by DIYAutoTune and was trying to let VE Analyzer build a VE table and the numbers were all over the place and constantly changing. The car would also backfire, shake, ran terribly. All that was solved by having the correct injector dead time.


Next up was finally getting to the ignition. Once again, I listened to Ed's recommendation and got MSD 8.5mm wire for the Ford/Hemi pro stock.
I decided for fun to test the wires with an oscilloscope and compare them to the OEM wires. I was quite surprised at what I saw, and have no explanation for it. If someone can enlighten us I would be glad.
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MSD wire is the yellow line, OEM wire is the blue line. I simply sent a 5V square wave using an Arduino and measured at the other end of the wire. The patterns are completely different and I would love to know why, and I know one is more desirable than the other.

Fitting-wise, I had issues with cylinders #2 and #3. There was no way the tubes would clear the Kenne Bell inlet, even cut at the shortest. I ended up removing the boots from the OEM-like wires, and used them on the MSD wire.
Motor vehicle Hood Automotive design Automotive exterior Gas

I went ahead and measured everything, made the wires, and checked the resistance (under 50 ohms per foot all the time), but after I had 6 wires all said and done, the seventh one had resistance in the kilo-ohms, sometimes even mega-ohms. It took me a couple of minutes to figure what was wrong. Turned out the wire wasn't crimped at the assembled spark plug side from MSD!
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This is what it should look like
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I assumed this was a fluke and proceeded to the next one. Same thing! I lost confidence, and good thing I did, all 8 of them weren't crimped! It's quite a job to remove the insulator and put it back in place, especially when the wires are fully assembled and the tube has to come from the side where it's not crimped before installation, except now it's crimped. There was a lot of grease used to be able to slip everything back into place which doubled the time required to do the job that was almost finished. I don't know if they are designed like that (I hope not), or if someone didn't do his job on my particular set. Learn from my mistake and check yours!

Here's the bracket I made to bolt the driver-side coil-pack since OEM is 4 bolt and those are 3 bolts, and not at the same location.
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I already had a custom-made bracket for the passenger side coil pack, I simply had to drill 2 more holes (and reused one)

I have two pressure sensors ordered (one for fuel pressure and the other for oil pressure). I will keep this updated as I work on this project. My plan is to use the option connector on the MS3 to wire those sensors.
Pin A will be ground, pin B will supply 5V to both sensors, C will be signal from the fuel sensor and H will be oil pressure.

That's it for now, I appreciate feedback, suggestions, comments, questions, etc

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Very impresssive, Michel. Those forums are the right place to communicate this stuff to DIY and the TunerStudio guys. I think the time is long past to revoke your learner's permit. :giggle: Your tuning instincts are excellent, and you are clearly working with real design improvements in the core fueling logic the ECU uses. Very impressive!
Thanks for the compliment Ed. I'm still new to this and have a lot more the learn but it's getting there. My full time job is programming, cars are an hobby so I enjoy this crossover a lot.

I'm quite surprise that something as simple as not retarting timing depending on load, tps, or other factor is still not implemented. It's been asked since at least 5 years, quite easy to do and many have the same issue I do. It's mind boggling why it's still not on their TODO list.

I noticed something scary in the datalog today. My injector duty cycle was 85% at 6000rpm with a Lambda of 0.7 (about 10% too rich). If my math are correct, I would hit 100% at 7000 rpms, which used to be my shift point, with those injectors, for the last 10 years! My goal with the MS3 was to be able to up the rev limiter to 7500 maybe 8000rpms. Clearly I can't do that with my Siemens Deka 80#. I will most likely get in touch with Greg Banish for a new set.
I remember some years ago, Injector Dynamics were recommended by everyone. Is it still the case or should I look elsewhere? Open to recommendations here, but I'd like to stay EV1 style.
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Michel, when you contact Greg, ask him to flow the injectors for the MS3Pro. He has a special flow program to produce all the necessary injector characterization data in MS3Pro format. I had him do a set for me. It is money well spent.
Michael,
What pump(s) do you have? PLEASE don't skimp on pumps and fueling. Looking in the archives there are a lot of broken motors b/c fueling was not adequate which is the ONE thing that I don't skimp on.

My fuel system consists of:
Three 450LPH pumps
1/2" feed and return lines
160# flow matched inj from Fuel Injector Connection
E85.
My duty cycle at 950RWHP (1200FWHP) was 70%.

Fueling is sooo important to me that I will have the injectors flowed/clean again after the head swap.

ks
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Michel, I should have commented on the pumps, and I did not, I am glad Kevin did. I was suffering from injector characterization myopia. What Kevin said is spot on. Go to the TToC and get the fuel system calculator out of the Fuel System section of the TToC and use it to size your fuel pumps. Historically we have shot for an 85% duty cycle on the injectors when the engine is at peak power. In years past, the rationale for this had more to do with high impedance, large injector availability, cost, and concern for idle quality. With today's injectors, you can pretty much get anything your heart desires, and idle quality is not the issue it once was.

One of the old-time members on the site, Mofasta, uses dual 2200 cc injectors because he runs methanol. At the end of the day, the fuel system gets flushed out with gas, and the car is operated on gasoline until the next outing. On gas, the engine idles at 850 to 900 rpm, give or take, on dual 2200 cc injectors with no issues! You can use the Fuel System Calculator <= clickable, to back into an injector size that requires, somewhere between a 50% or less than 60% injector duty cycle at WOT. That will give you plenty of headroom, and the engine will still have an excellent idle!

Like Kevin is suggesting, you want to stay as far away as possible from under-fueling the engine at WOT. With a close but no cigar fuel delivery, you will accumulate damage to the pistons and fail progressively over time rather than a sudden and massive engine failure — although those are in the offing also if you put the engine on too lean a diet. It is easy to be safe today; we don't have the fuel pump or injector restrictions we had 20 years ago.
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Sorry for the late reply, I somehow didn't get the notification there as new reply to this thread. I believe my fuel system is adequate but I think about changing it for next year. It's been good enough for a decade but I could be better now.

I have 2 GSS340 pumps (255lph), connected to a Boost-A-Pump to make them run at 17v. I tested them last Winter. Free flow, they gave me close to 500gph so they're still good. I have a 04 Cobra fuel tank. My fuel hat is custom made from that tank with a bung for the return line that ALWAYS leak a few weeks after I reweld it, I'm getting so tired of that and that's what fueled (see what I did there) the desire to change my fuel system to a returnless. I have -6AN lines out of each pumps, to a Y block, then a single -8AN line to the fuel rails, then the regulator, and a -6AN back to the tank.
On the datalog, fuel pressure was stable, not dropping so pumps were still enough. Meanwhile, my injector duty cycle at 90% at just 6000rpm, dangerously close for 7000rpm action. It can get there because I was running way too rich, but that's still be 100% injector duty cycle. Way too close for comfort and will upgrade the injector this summer. Thinking of going with Fuel Injector Clinic since I have a local friend who have a shop that sells them (Billet Pro Shop). Not sure what size, their calculator say I'm good with 850cc but I already have 800cc so..... yeah. I'll get the 1000cc or 1200cc and be done. They are flow matched, come with a nice datasheet and all the spec to enter directly on the MS3 which is very nice.
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Some of you may have already saw my other post, but the issue I was fighting last Autumn is now solved thanks to the MS3. I did a pull up to 6600 RPMs and everything was fine. There is still many smaller issues I need to work on and I will post when I have a solution for each of them.

First I found the culprit for something weird that happened more than once. I would consider it a bug in TunerStudio. Some screen share the same Y-bin table. Example, Warmup Enrichment (WUE) and Cold Advance. If you change the coolant temp in one screen, it also change it for the other one! This explains why randomly, my last row in WUE was not 100% and fueling was off. Playing with Cold Advance was changing my Y-axis for the WUE. I digged in the configuration file in tuner studio and found this bin table named "tempTable" is being used in those 4 table:
  • Stepper Idle Warmup Position
  • PWM Idle Warmup Duty Cycle
  • Cold Advance
  • Warmup Enrichment (WUE) Curve
Changing it in any of those, change it for all of those. There may be other bins that are shared in weird places that I haven't discovered yet.

Other thing I now qualify as a bug is sometime, the triggered datalog is not saved, and that's sad. I have TunerStudio setuped to automatically start datalogging with the condition rpm > 100, and stop when rpm < 100. This works 95% of the time. Before doing my WOT pull earlier, I double checked and the "Data logging" indicator was lit so it was supposed to datalog. I did my thing, went back to the garage and when I went to the datalog folder, nothing recorded :( Luckily enough, I had all the infos needed on the MS3 SD card. There's less detail, but the essential is there.

About that datalog? Here's a quick screenshot
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Don't mind the fuel pressure number, it's wrong as discussed in previous posts. What's concerning is that it was slowly dropping. Also, duty cycle was 89% at 6600 RPMs. Way to close for comfort for my regular shift point of 7000 RPMs, and plans of going close to 8000 RPMs are cancelled until further notice. I will need to buy new injectors. Still undecided on the size. My current favorites are Fuel Injector Clinic 1200CC => 1200cc (110 lbs/hr at 43.5 PSI fuel pressure) FIC Fuel Injector Clinic Injector Set for Mustang GT (1987-2004)/ Cobra (1993-1998)(High-Z). They have all the data ready to go in the MS3, flowmatched with a datasheet etc. After that, I may need new fuel pumps, and if I want to go return-less in the future, it will be the time to do so.
Quick question about those injectors: all the data they give is at 3 Bars / 43.5psi. Does that mean I should adjust my regulator to 43.5psi, or scale the data to 39.15psi? My feeling is telling me to up the pressure but just want to be sure before making a mistake.

Final issue for today (don't worry, there is more), I still get some random stalling. It's not because of MAT-retard anymore since I have disabled that. I have a datalog of this happening just as I was parking in the garage. I tried to make a screenshot but it was too messy so I have attached a datalog in case some one want to dig a little bit. I'm not sure yet why it does that. Timing and AFR is correct when it's happening. Again, since this forums doesn't accept .msl file I renamed it .txt and you would have to renamed it to msl to open it with MegaLog Viewer.

While I'm at it, I added the WOT datalog just for fun if anyone is interested

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I'll look at both the data logs later this week to see what I can, Michel.

With respect to the bugs you have detected, be sure to communicate them to the TunerStudio guys. They are receptive to identifying and fixing bugs as we discover them. You can use the Fuell System Calculator to size a new set of injectors for the engine, or you can use a purpose-built fuel injector sizing calculator that Black2003Cobra built more than 15 years ago. You can find Black2003Cobra's purpose-built calculator in the TToC under the Fuel System Tech section of the TToC. It is the third entry on the list.

Back in the day when this calculator was crafted, we did not have as broad a range of high-impedance injectors then as compared to today. Additionally, the few we did have, at the time, were quite expensive as you went up in flow capacity. Today we have an excellent range of high-impedance injectors available all the way up to 2200 cc units. Both because of cost and availability, at that time, we would run higher than Ford OEM base fuel pressures to squeeze the most we could out of an injector. We would also run high-duty cycles to again extract as much performance as possible out of a particular injector.

The third leg on this milk stool is the low slope injector performance. It was measurably different than the high slope performance and affected idle and tip-in-throttle performance, which frequently was where the engine was operating. Today's injectors are measurably better than 20 years ago. You can use amazingly large injectors and still get a decent idle which adds up to buying injectors less often. Try using a 50 or 60% duty cycle for the injector in the calculator. It will call out a larger injector for you. Whenever possible, describe the injector using injector cc's rather than injector #/hr as the sizing metric, it is more precise.

Almost forgot, one other consideration when using injector sizing calculators; most calculators rely on a BSFC metric to size the injector. BSFC varies from engine because it is derived, and predicated on the actual in-service performance of various engine design metrics, including such things as compression, engine efficiency, supercharger adiabatic compression efficiency, internal engine friction, and others. All this makes BSFC challenging to specify accurately. The calculator that Black2003Cobra built uses a Brake Specific Air Consumption (BSAC) model, which completely sidesteps all these variables and just looks at the air the engine consumes to determine the required injector. Very clean and very accurate. It is a vastly superior approach to injector sizing.

BTW the reason for using the 39.15 psi base fuel system pressure is, it lowers the max fuel system pressure required at WOT. Because the ECU needs to know the differential pressure across the injector for fueling, as the FRPS reports back the measured manifold boost, the ECU commands higher fuel pressures to maintain the commanded 39.15 psi injector differential pressure and tuner specified target lambda. 20 psi of manifold boost will add 20 psi to the fuel rail pressure and perhaps another 5 psi way back at the pump. The additional fuel system pressure takes electrical power and can tax the car's in-car electrical system, possibly past safe operating limits. When that happens, the car goes lean, and something gets hurt — typically a piston.

Use 39.15 or 3 BAR (43.5 psi) for your base fuel system pressure. If you use 39.15 be sure to tell the calculator so it sizes for that. If your fuel system has been set for a 43.5 psi base fuel system pressure, stay with it and use 3 BAR (43.5 psi) injector sizing. Just be consistent. Both base fuel system pressures work as long as you maintain consistency. Do not go above 3 BAR. There is no need to with today's injectors.
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I just wanted to chime in on the fuel pressure sensor issue. I am currently fighting the same problem, and have not really found the cause yet. I am using the low-dollar sensors, and an also on my second failure in the same method as you. mine is also mounted on the fuel rail. I'll have to check the temp on it sometime, but it gets pretty warm.
I have a mechanical gauge installed somewhat permanently, and use that to verify the sensor is losing about 14psi.
I think I will have to contact low-doller again and ask their opinion on the issue.
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Thanks a lot for chiming in. I have the exact same results as you, about 14psi too low when it's hot, at cold it's almost dead-on. I think the best option is to listen to Ed and get a Ford manifold-referenced differential pressure sensor (FRPS) as he mentioned in post #73.

I did fiddle around the Fuel System Calculator in the last few days. To make sure I was understanding everything I tried to input what I currently have and check how close it is to reality.



As it is, I should hit 90% duty cycle if I had 65# injectors, but I have 80# so there's still something not perfect.
Let say I want to hit 8000 rpms, a little higher Ve for future upgrade, and 60% duty cycle, that's what I should need:



If I'm right, that's in the territory of 1440cc at $1400. For $150 more I could have 1650cc, and $85 on top of that would get me 2150cc which would 100% be the last injectors I would ever need to buy. But do I need to spend $230 more than necessary? Only I do and I still haven't made up my mind.

Next up is fuel pumps. I noticed a little pressure drop at higher RPMs, but I'm not 100% sure if it's really dropping of if it is the sensor. According to the calculator, I should be using 466lb/h of fuel, which is quite close to what 2x255lph pumps can supply, even at 17v. And I'm only talking about the 6600RPM I went, not may normal shift point at 7000.

When I built this fuel system about 10 years ago I thought it was the one and only time I was working on that and that would be good for the life of the car. Turn's out I'm back to the drawing board. I will do the injectors this summer, then I need to decide if I convert to returnless. If so, that's a Winter project, otherwise I will have to shop for fuel pump(s) sooner than later.
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Apologies Michel, I didn’t mean to put you through all those pushups. Here is an easier way to the injector sizing. If you use my Fuel Systems Calculator out of the TToC, it will be a bit easier. I don’t recall, but I think you either have a KB 2.4 or 2.6 blower. If that is the case, then Calculator page 1 looks like this:

This combination of pulleys and blower will produce ~16 lbs of boost depending on local temperature and altitude.

Calculator Page 2 will look like this:

At a 60% duty cycle, you will require 912 cc’s injectors at 3 BAR, which is the rough equivalent of an 87 LB injector. They don't exist! Whenever buying injectors, go by the cc’s/min rather than the lbs equivalent metric. The cc’s metric is more precise.

That’s it! You basically want a set of 900 or 1000cc injectors. Remember what I said about using cc’s rather than lbs. BTW that, 11.2:1 AFR is not a typo. That is the correct AFR for E-10.

Apologies I should have sent you this way instead of the other. Both work and will give you correct answers; this path is just easier and faster.
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Michel,

I have looked through the data logs, and I think the triggering event is attributable to a loss of Fuel volume. The engine shut down / rpm drop occurs as the engine goes lean — as if the fuel pumps had shut down. The fuel pressure and AFR begin to badly misbehave T=1225 seconds prior to the engine coming to a complete stop. Prior to that, the engine is still lean, just not shut down lean.


You can see the yellow AFR curve head for the sky ad simultaneously the engine shutting down. I suspect that the shutdown has to do with fuel delivery that is being squeezed off, producing the lean AFRs and eventual engine shutdown. Perhaps a bad sensor, a table calibration whoops, or ??? Whatever the shutdown gremlin is, I believe it is fuel delivery related.

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Humm.... something is definitely wrong here. I found your calculator and entered the correct values for my car. It's a 2.6H, crank pulley is 7.5" and blower is 3.25". I used 11.25 AFR as I'm on E10 and targeting 0.75 Lambda, will lean it out later to 0.78 - 0.80.
18.4psi is spot on as I datalog 18.2psi usually. My IAT2 is often around 150F.





This means I should be at 65% duty cycle on my 80#.
Maybe I have something wrong in the tune that overuse the injectors. I don't know if injector timing, dead time, or something else would cause that.
I agree about using CC, but they are Siemens 80#, I'm not even sure if they are 800cc or 840cc as I've found both number. Judging by your calculator, I'd say they are 840cc.

This also means that my twin 255lph pumps are plenty if only 262lph is required.

On the stalling issue, this may very well be fuel related. I suspect something is of with the fueling when MAT is high. Having the engine idling reduce the air flow and drives the MAT higher. When I start the car dead cold, AFR is perfect. But if I stop it for even a couple seconds, it will go very lean. It recovers, but never as good as if I would not have stopped it. Since this was the second drive of the day with a 10 minute rest time, that may be it. Now to figure what needs to be changed where.... As I said, I still have a lot to learn on tuning.

Quick side note as this is beginning to be a long post, I did inform the guys about the table being shared between features. It's because they are shared in the firmware (not Tuner Studio's problem), but they should be read-only, so no risk of doing what I did. The issue is about something being case-sensitive and the read-only is not being respected. To have independent table for the features that share this table, it would require modification on the firmware.
For the datalogging issue, funny enough, on the same day I posted about that, James (the developer of the MS firmware) posted about that same issue he is personally experiencing. It may be caused by having CAN devices connected to the MS3. Both of my wideband controllers are connected via CAN so that may be why. They are investigating this issue.
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I don't recall anymore, but I want to say the FRPP 80# Siemans DEKA injectors are 840cc injectors at 3 BAR. The wrinkle in the bed sheets is Ford uses a different base fuel system pressure, and I believe their BAR figure is something like 2.7 BAR, but I know the pressure in psi is 39.15. These numbers are only important when you are using Ford parts. Once you go aftermarket, you should use 3 BAR for simplicity. That is the pressure all injectors are sized at. There is no good reason to continuously convert back and forth between Ford and the rest of the world.

This is an upgraded AFR table I will add to the next version of the FuelSystem Calculator;


You will notice the line in the sand for E-10 is 0.8 lambda or 11.26 AFR, and that assumes your wide bands have been calibrated for E-10.
Additionally, I richened up all the other fuels comparably. I have no first-hand experience with E-85 or E-100, so those redlines were empirically established. I do have first-hand experience with both methanol and nitromethane in supercharged engines. Those redlines are personal experience.

All of the don't go leaner barriers are for after the car is launched. To use methanol as an example, in a racing application the launch AFR would be around .55 lambda or an AFR between 3.2 and 3.5. Once the car got out in first gear, you could lean it out to about a 3.7 AFR which is still a whisker on the rich side. The reason for erring on the rich side is methanol loses little if any power when it is a 'whisker' rich; however, you drop combustion and exhaust temperatures making parts live longer without sacrificing any performance. On the street, this would give bad mileage, but that is about all. With a fuel like E-10, running rich would shorten plug life and also cost you mileage.

The rich launch is because we take first gear away from the car to keep from blowing the tires off when you launch at WOT. As soon as you can black track without breaking loose, you have the right first gear starting line launch ratio. It will always be a combination of transmission first gear, ring and pinion, tire size, and car weight. It will also be elusive.

Cruising on the street or highway, you can easily head towards a Lambda 1.0 figure for cruising and mileage reasons. This kind of driving places little to no load on the engine. The lean mixtures work fine for cruising and will also provide good mileage. Be sensitive to not using enough fuel to keep the engine happy when under load. For E-10, I start getting antsy right around 0.8 lambda. Experiment cautiously, with your own engine, car, and driving style. The engine will talk to you and let you know if it is uncomfortable. There is a good post I did a while back on reading plugs. Here is a link to it, click here => Reading Plugs. You can also find it in the TToC under Tuning. It will be the last entry in the Tuning section

Methanol is the easiest fuel to read, and predictably gasoline is the most difficult. It has to do with how clean the fuels burn. When you attempt to read the plugs, it should be a new set after one pass at the track. It is impossible to 'read' street-driven plugs.

Almost forgot. Do not pay too much attention to the IAT2 temp field. I have disconnected it for the time being. I want to do something different with it going forward. The IAT1 and the Altitude fields do impact the air density the engine inhales. You can get your local altitude off your smartphone these days.
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Forgive me for side tracking the thought process but I will admit that the conversation took a turn beyond my knowledge, however, let me toss this out there for a second:

How long in seconds is the fuel pressure falling? ie How long is the run?

On my last dyno day I had serious issues of not having enough fuel despite the three 450 pumps and #160 injectors BUT what we soon reasoned was the tubing from the manifold to the regulator was too small to feed the regulator diaphragm "fast enough" to ramp up the fuel pressure. The tubing size is 5/32" but couldn't flow enough air to pressurize the regulator to raise fuel pressure before the dyno pull was done. The motor was running waaaay lean for the few seconds that a dyno pull was done. So we added 20psi to the base fuel pressure then the fueling for WOT was right on par.

In a nutshell I need much Larger tubing feeding the regulator to keep the fuel pressure up in order for the regulator diaphragm to get pressurized faster.. Maybe this has nothing to do with what you are experiencing...

ks
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That is a real possibility, Kevin. It is the reasoning behind why I like the Bosch integrated MAP and IAT2 temp sensors. With an electrical connection instead of a vacuum line, the messaging between the sensor and the ECU is instantaneous and 100% accurate. The long vacuum line required to use the onboard 4 BAR MAP sensor introduces a delay in messaging for the built-in MS3Pro MAP sensor. That same delay, in the case of a fuel pressure regulator and a small-diameter tube, can cause the regulator to be slow on the draw in responding to rapidly changing MAP-based fuel demands, as you have already discovered.

While increasing tubing ID fixes one dimension of the problem, it aggravates another. The increased volume of the larger diameter tubing takes more time for the rising or falling manifold pressure signal to travel the length of the tubing after we increase the diameter. Sort of a damned if you do and damned if you don't kind of dilemma. That said, if I am using tubing to monitor MAP, my preference is usually bigger rather than smaller. You can measure the effect using a few feet of small-diameter and a few feet of larger-diameter tubing. When you apply pressure to the far end of the tubing and watch the gauge, it will take a second or so to register the correct pressure. Same dynamic but different timing when you apply a vacuum at the far end. The gauge will not respond immediately. That delay can be problematic depending on your boost level, the engine loading, and the compression ratio.

While this might be the origin of Michel's fueling problem, the whoops might also be rooted in the hot start mischief he has discovered. I honestly don't know which is the bad guy or if both are contributing factors — a more likely scenario. That said, probably because I am troubled by the hot start issues, I am suspicious of the fueling issue being more rooted in the hot start bed of snakes. I could easily be flat-out wrong. This is going to take a little old-fashioned science-project-style experimentation to find the bad guy.
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Ed, I don't remember having to configure my wideband for a specific fuel? It's part of the reason why I choose to tune in Lambda because it should be fuel independent. In all case, I'm using Spartan 3 controller with Bosch LSU ADV.

Kevin, it was a very short quick pull on the highway, about 3.5 seconds.



There was about 0.5 second between the time my foot hit the floor (and I did not slam the pedal), and the time I had full fuel pressure. Also, my foot was not even on the floor yet and the widebands were already reading quite rich. The response time, while far from being as fast as the speed of electricity look ok to me in this graph. The T-MAP sensor Ed suggested is still in the shopping cart and is a mid to short term project.

I think I need to make longer pull to get a better picture of the fuel drop. That means, I need to go to the track because it's getting way to fast /dangerous for highway driving.

What I'm suspecting, is something wrong with the timing of the injectors. I have cams with bigger duration than stock. Maybe some part of the fuel goes right out the exhaust valve unburned, justifying why the injectors need to dump so much fuel while the AFR is still where it's needed. That would also explains the 25l/100km the car is burning.

With everything I learned lately, I can explain why a couple weeks ago I had fouled spark plug to the point of not being able to start the engine. I would sometime start the car at lunch time and tune some things. Then, when work was over, about 5h later, I would something do another run of tuning and the engine would run crazy lean. More than once I had to start over my Ve table when this was happening. I was giving it way more fuel to keep the engine happy. Then the next day, at lunch, it would run stupid rich. Going back and forth like that is what fouled my plugs and cause the no start condition I was experiencing. Now I know to only play with the Ve table on the first start of the day. That will also be a big problem if I go the the track, because it involves a lot of start and stop. I need to figure out this issue, and I know MalcolmV8 is having the same problem. This is being my most critical issue because I can't go to the track until it's solved, and I need to go to the track to check fuel pressure and everything else.
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Ed, I don't remember having to configure my wideband for a specific fuel? It's part of the reason why I choose to tune in Lambda because it should be fuel independent. In all case, I'm using Spartan 3 controller wish Bosch LSU ADV.

Kevin, it was a very short quick pull on the highway, about 3.5 seconds.

View attachment 176646

There was about 0.5 second between the time my foot hit the floor (and I did not slam the pedal), and the time I had full fuel pressure. Also, my foot was not even on the floor yet and the widebands were already reading quite rich. The response time, while far from being as fast as the speed of electricity look ok to me in this graph. The T-MAP sensor Ed suggested is still in the shopping cart and is a mid to short term project.

I think I need to make longer pull to get a better picture of the fuel drop. That means, I need to go to the track because it's getting way to fast /dangerous for highway driving.

What I'm suspecting, is something wrong with the timing of the injectors. I have cams with bigger duration than stock. Maybe some part of the fuel goes right out the exhaust valve unburned, justifying why the injectors need to dump so much fuel while the AFR is still where it's needed. That would also explains the 25l/100km the car is burning.

With everything I learned lately, I can explain why a couple weeks ago I had fouled spark plug to the point of not being able to start the engine. I would sometime start the car at lunch time and tune some things. Then, when work was over, about 5h later, I would something do another run of tuning and the engine would run crazy lean. More than once I had to start over my Ve table when this was happening. I was giving it way more fuel to keep the engine happy. Then the next day, at lunch, it would run stupid rich. Going back and forth like that is what fouled my plugs and cause the no start condition I was experiencing. Now I know to only play with the Ve table on the first start of the day. That will also be a big problem if I go the the track, because it involves a lot of start and stop. I need to figure out this issue, and I know MalcolmV8 is having the same problem. This is being my most critical issue because I can't go to the track until it's solved, and I need to go to the track to check fuel pressure and everything else.

My bad on the O2 sensors, Michel. I forgot you were using the Spartan 3 units.
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