As the title says, I'd like to open up a discussion on engine tuning with a piggyback or standalone ECU. Feel free to post up any questions you have and I'll do my best to answer them here. We're gearing up for a video series covering various tuning topics, so any questions that are asked here may end up as the basis for a video segment.
Ask your tuning questions here; open discussion thread on engine tuning.
- Thread starter Zach
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Ok so I just put 264 cams in my 7M running on a MAFT Pro speed density. I had to pull quite a bit of fuel at idle-2k to get the wb back to stoich at idle and cruising, is that normal? I guess what I should be asking is I've never had the ability to tune a car when upgrading cams before, what should I expect to have to do to fuel, timing, etc? Should i be bringing the WB back to stoich when tuning outside of WOT? Quick setup is 560cc's, forged bottom, ported head, upgraded springs, turbonetics bolt on 63 trim, fmic w/pipes, 3" catback.
There's very rarely a free lunch when it comes to increasing power output. Going with more aggressive cams will typically improve breathing at high RPM, but usually at the expense of efficiency down low. Your car simply isn't moving the same amount of air at low load/RPM as it did with stock cams, so you had to trim the fuel map to match. You should also expect to have to add fuel up top since the efficiency increased in that range.
With speed density calculation your fuel delivery is calculated by a table that represents how efficient your engine is at different points as you change RPM and inlet pressure (pressure in the intake manifold). Changing a part like a camshaft directly changes the efficiency, so you have to retune. With a system that uses a direct measurement for airflow (like the stock MAF), fuel calculations are based primarily from a direct measurement of the volume of air entering the engine, so the efficiency increase due to cams would be accounted for automatically.
Stoich is fine for part throttle cruising and idle, and if the stock ECU is still seeing the O2 sensor then it'll try to keep it there. Depending upon how aggressive your cams are in terms of overlap, you may find that a slightly richer mixture runs more smoothly. Lots of overlap will lead to an increase in unburnt fuel being pumped through the engine when both the intake and exhaust valves are open, and indicating a leaner mixture on the wideband than what the cylinders are actually seeing. 264s aren't too aggressive, but it's something to experiment with to see if it runs better.
Adjusting timing is something that should be done on a dyno (or using the Virtual Dyno feature of our DET3 or EMU, shameless plug). That's something that really needs to be tuned for effect, and with pump gas you don't want to get too greedy since fuels aren't terribly consistent and the stock ECU doesn't have great knock control.
With speed density calculation your fuel delivery is calculated by a table that represents how efficient your engine is at different points as you change RPM and inlet pressure (pressure in the intake manifold). Changing a part like a camshaft directly changes the efficiency, so you have to retune. With a system that uses a direct measurement for airflow (like the stock MAF), fuel calculations are based primarily from a direct measurement of the volume of air entering the engine, so the efficiency increase due to cams would be accounted for automatically.
Stoich is fine for part throttle cruising and idle, and if the stock ECU is still seeing the O2 sensor then it'll try to keep it there. Depending upon how aggressive your cams are in terms of overlap, you may find that a slightly richer mixture runs more smoothly. Lots of overlap will lead to an increase in unburnt fuel being pumped through the engine when both the intake and exhaust valves are open, and indicating a leaner mixture on the wideband than what the cylinders are actually seeing. 264s aren't too aggressive, but it's something to experiment with to see if it runs better.
Adjusting timing is something that should be done on a dyno (or using the Virtual Dyno feature of our DET3 or EMU, shameless plug). That's something that really needs to be tuned for effect, and with pump gas you don't want to get too greedy since fuels aren't terribly consistent and the stock ECU doesn't have great knock control.
Processing power has virtually nothing to do with it, an engine at 9000 rpm may as well be standing still compared to any modern processor. Fast processor speeds make for good marketing bullet points, but it has no direct correlation to performance.
Here are the biggest factors in terms of idle quality:
Cam profile- the more aggressive it is, the more difficult it will be to get a stable idle. Like I mentioned before, lots of overlap causes unsteady combustion at idle (meaning under the exact same measurable conditions, combustion is different from one cycle to the next).
Injector flow rates- If you have large cylinder to cylinder variations in flow rate at small pulsewidths (not static flow rate), then you'll have a very difficult time locking down a stable idle.
Injector nonlinearities- Some larger injectors have nonlinear behavior at small pulsewidths (usually under 2 milliseconds), meaning that there's not a predictable link to how long the ECU gives it a signal to open and how much fuel is delivered. We plan to add a table to our software so that you can define this curve at small pulsewidths, but there are several cars running ID2000s with our EMU on gas with small cylinder sizes and have no issues with idle quality. Some other injectors have far worse behavior at small pulsewidths, but you don't see too many of them these days.
Sequential vs. semi-sequential fueling- If you're running a stock 7M or 1JZ (JZA70) ECU then you have three injector channels with 2 injectors on each channel. This won't pose a problem with idle quality until you start running larger injectors. Switching to sequential fueling allows you full control over the injection event, meaning you can adjust the timing of the injection event relative to intake valve opening event. Open versus closed valve injection is a topic for another time, as that's a bit of a lengthy explanation.
Here are the biggest factors in terms of idle quality:
Cam profile- the more aggressive it is, the more difficult it will be to get a stable idle. Like I mentioned before, lots of overlap causes unsteady combustion at idle (meaning under the exact same measurable conditions, combustion is different from one cycle to the next).
Injector flow rates- If you have large cylinder to cylinder variations in flow rate at small pulsewidths (not static flow rate), then you'll have a very difficult time locking down a stable idle.
Injector nonlinearities- Some larger injectors have nonlinear behavior at small pulsewidths (usually under 2 milliseconds), meaning that there's not a predictable link to how long the ECU gives it a signal to open and how much fuel is delivered. We plan to add a table to our software so that you can define this curve at small pulsewidths, but there are several cars running ID2000s with our EMU on gas with small cylinder sizes and have no issues with idle quality. Some other injectors have far worse behavior at small pulsewidths, but you don't see too many of them these days.
Sequential vs. semi-sequential fueling- If you're running a stock 7M or 1JZ (JZA70) ECU then you have three injector channels with 2 injectors on each channel. This won't pose a problem with idle quality until you start running larger injectors. Switching to sequential fueling allows you full control over the injection event, meaning you can adjust the timing of the injection event relative to intake valve opening event. Open versus closed valve injection is a topic for another time, as that's a bit of a lengthy explanation.
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You'll need to use one of the latest versions of the firmware for use with the stock multiplex ignitor. Send me an email at support@ecumasterusa.com and I'll provide you with a base map.
Thanks!
Thanks!
Send me an email with your current map and a log of you trying to start it. Also, include what firmware version you're using. There's a video on our youtube channel that shows you how to save a log. Email the info to support@ecumasterusa.com
I use the apexi safc2. I have low throttle at 30, high at 70. I have the lexus afm, 550's, and afpr. Also a very large intake manifold and throttlebody. For some reason the safc has to be set at 25% to be at 14 on wideband. But the ecu and SAFC are fighting eachother. The wideband sweeps back and forth and back and forth. Im rich one minute and lean as hell the next.
Hi there,
The car I’m working on is a 1988 Toyota Supra Turbo (7MGTE).
Preparing to install the unit and was checking configurations. I do have a couple of questions that I’m hoping that you can answer.
I have the classic with a plug and play harness adapter.
Thanks!
The car I’m working on is a 1988 Toyota Supra Turbo (7MGTE).
Preparing to install the unit and was checking configurations. I do have a couple of questions that I’m hoping that you can answer.
I have the classic with a plug and play harness adapter.
- FPR signal seems to be mapped to pin 5 Grey (AUX 3), but physically the wire goes to pin 6 Grey (Injector #4.) I’ve re-pinned to 5 Grey, is this correct?
- Both my RC 550cc injectors as well as the stock 440cc injectors are low impedance. Based on the EMU manual, it is necessary to install a 4.7 ohm 50W resistor inline to limit the current. Is this correct, or is there another current limiting circuit somewhere between the ECU and injectors that would remediate the issue?
- Do any of the standard connections (PnP harness wired pins) require the flyback diode? It doesn’t look like it, but just wanted to verify that I hadn’t missed something.
- IAT signal in the PnP harness (21 Blk) goes to THA (Air Temp Sensor.) When I install the GM IAT sensor, I should sever that connection and take one lead to 21 Blk and the other to Gnd, correct?
Thanks!
1. That was the issue I had as well and I moved it to gray 5. You can change the settings under the software to any open pin available under your settings.
2. No, as long as the new injectors are low independence you keep it wired up like it is. I am running sequential injection so I got a Acura Legend fuel injector resistor box so I can have 6 separate injector channels.
3. Not that I seen. I am not running any.
4. Correct. Polarity does not matter either on the GM air intake temperature sensor.
2. No, as long as the new injectors are low independence you keep it wired up like it is. I am running sequential injection so I got a Acura Legend fuel injector resistor box so I can have 6 separate injector channels.
3. Not that I seen. I am not running any.
4. Correct. Polarity does not matter either on the GM air intake temperature sensor.
Any the ECU masters classic or black standalone's can be used with any of those motors you listed plus tons more... Just as you stated, you just have to repin a few things according to the motor you are using and download a base map or make your own. I am running the ECU Masters classic and I used both the 7mGTE pigtail harness (which I am selling now) and made my own engine harness to plug directly into the standalone.
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IchibanEye
Thank you for the prompt reply. I'd like your personal opinion too if you wouldn't mind that is? Anyone else feel free to chime in on this too please. Okay comparably based on features, quality and price what do you think of the Aem v2 when compared to either your emu black or the classic? I found a V2 for $900 most likely he'll take $800. However I think I need to make sure it's for the 88' and under years [yellow plug/harness?] and not 89' above? I'm not sure though. I'm looking to get a stand-alone by summers end. It's about time I've started to add the needed supporting goodies to my baby that was built to go, go, go more than that factory blow, blow, blow. Cheers!
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No problem. For me I originally wanted to go with the AEM V2 but after seeing the support for the V1 drop fast when the V2 came out and hearing issues people had with the CPS unit/ignition I decided to research a bit more. 3 other local supra owners I have talked with liked their ECU Masters classic unit and for the features, fail-safes, built-in map sensor, capable of powering ignition coils, lifetime support/firmware upgrade and price it was a win-win. I made 366whp on the first and only untuned dyno pull and will be in the 500 to 600whp range on e85 once the final tune is done.
The standalone did have some hiccups in the beginning but after learning more about the software hands-on and talking advance features with my tuner, things are making much more sense now.
Personally for around that price, DM offers a new ECU Masters classic standalone for $899 with warranty and everything new in the box. I have the barley used 86.5-88 yellow style plug-in-play adapter for the classic which I am selling:
I do not need it because I built a new engine harness from scratch so I pined everything to plug directly into the standalone and body plugs.
Overall I am now a person who would recommend this standalone to anyone as well. I am starting to see more builds use this standalone on YT and as time goes on, this company will become more and more mainstream.
The standalone did have some hiccups in the beginning but after learning more about the software hands-on and talking advance features with my tuner, things are making much more sense now.
Personally for around that price, DM offers a new ECU Masters classic standalone for $899 with warranty and everything new in the box. I have the barley used 86.5-88 yellow style plug-in-play adapter for the classic which I am selling:
I do not need it because I built a new engine harness from scratch so I pined everything to plug directly into the standalone and body plugs.
Overall I am now a person who would recommend this standalone to anyone as well. I am starting to see more builds use this standalone on YT and as time goes on, this company will become more and more mainstream.
Likes:
IchibanEye
No problem. For me I originally wanted to go with the AEM V2 but after seeing the support for the V1 drop fast when the V2 came out and hearing issues people had with the CPS unit/ignition I decided to research a bit more. 3 other local supra owners I have talked with liked their ECU Masters classic unit and for the features, fail-safes, built-in map sensor, capable of powering ignition coils, lifetime support/firmware upgrade and price it was a win-win. I made 366whp on the first and only untuned dyno pull and will be in the 500 to 600whp range on e85 once the final tune is done.
The standalone did have some hiccups in the beginning but after learning more about the software hands-on and talking advance features with my tuner, things are making much more sense now.
Personally for around that price, DM offers a new ECU Masters classic standalone for $899 with warranty and everything new in the box. I have the barley used 86.5-88 yellow style plug-in-play adapter for the classic which I am selling:
I do not need it because I built a new engine harness from scratch so I pined everything to plug directly into the standalone and body plugs.
Overall I am now a person who would recommend this standalone to anyone as well. I am starting to see more builds use this standalone on YT and as time goes on, this company will become more and more mainstream.
The standalone did have some hiccups in the beginning but after learning more about the software hands-on and talking advance features with my tuner, things are making much more sense now.
Personally for around that price, DM offers a new ECU Masters classic standalone for $899 with warranty and everything new in the box. I have the barley used 86.5-88 yellow style plug-in-play adapter for the classic which I am selling:
I do not need it because I built a new engine harness from scratch so I pined everything to plug directly into the standalone and body plugs.
Overall I am now a person who would recommend this standalone to anyone as well. I am starting to see more builds use this standalone on YT and as time goes on, this company will become more and more mainstream.
I've thought it over and good deal or not I'm passing on the V2. Like you've mentioned it just can't compare to others out the with more options for monitors and fail safes. Most built in too without having to purchase more add-ons or paying for extra relays and technical support and so on.
I think AEM is looked at or mentioned so much because they've been around for so long and have a big fan base. Im guilty of this myself but never sold on anything until all the research is done and then a decision is made.
So you're still rocking the classic but just constructed a whole new harness is all then? Decent numbers on that raw run too. What turbo was run and boost level on that solo pull?
By the way that's one clean looking adaptor. Im curious what's your asking price on that?
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I was also the same way with the top name brand players in the car world but some of these smaller upcoming companies are disrupting the scene. From what I was also told about the v2 is that is is not really meant for a mk3 supra (like the v1 was) but is actually a Honda version tweaked to work for the mk3 Supra.
Yes, I been on the classic this year. I took a OEM supra engine harness apart for reference this last winter and made a new harness using over 300 ft of high quality wiring. Check out my build for some pictures.
I also have a YT video of that first pull on my build thread if you wanted to check it out. I am running the Sound Performance 6262 turbo but it was over boosting due to the wastegate not opening up sooner. Once the turbo was bench tested, I found out later that it opens up around 23 psi which is probably one of the highest opening internal wastegate's that I have seen. My tuner told be with that boost level you can only run e85. I have the new lower psi wastegate installed on it now so the boost solenoid can do its job properly.
Yes, I been on the classic this year. I took a OEM supra engine harness apart for reference this last winter and made a new harness using over 300 ft of high quality wiring. Check out my build for some pictures.
I also have a YT video of that first pull on my build thread if you wanted to check it out. I am running the Sound Performance 6262 turbo but it was over boosting due to the wastegate not opening up sooner. Once the turbo was bench tested, I found out later that it opens up around 23 psi which is probably one of the highest opening internal wastegate's that I have seen. My tuner told be with that boost level you can only run e85. I have the new lower psi wastegate installed on it now so the boost solenoid can do its job properly.
I bet that new harness works great. Did you gain better conductivity electrically with the better wire? I'd be brave enough to mess with wiring if I was around someone to learn from, with reading and all it's just not enough for me to feel comfortable jumping into anything major. I learn best with study and hands on time coupled together. I know I'm most likely my own worst enemy here so for now I choose wrenching and bloody knuckles over wiring any day. I'm truly grateful for the people [you included] here detailing their wiring adventures it's a huge help.
Is that beauty an 88' hardtop? What's the interior color on her? If it's grey we've got the same exact ride. Mines minus the abs though but has everything else. I love the better feedback of standard powered brakes.
Is that beauty an 88' hardtop? What's the interior color on her? If it's grey we've got the same exact ride. Mines minus the abs though but has everything else. I love the better feedback of standard powered brakes.