The beginnings of a Megasquirt how-to guide

[BackWoodsBob]

Would seriously be my hero at least!

[icingdeath88]

Thanks, guys I really appreciate the moral support.

Originally Posted by 2006eg33

glad to see full documentation of this.

you could effectively end the enginemanagement woes with this engine.

you'd be a hero.

When you had the MS hooked up to the EG33, did you have any sync issues? I could not get it to sync with the MS3 VR sensor circuitry, no matter how much I turned the pots. Had to switch to the Dual VR board I posted about before. That is only a $35 expense, but one I'd rather be able to eliminate for anyone else trying to do this. Also, the difficulty level of the soldering is just a little more than most people would want to attempt I think, especially with a ~$600 ECU at risk.

[BRZCory]

Originally Posted by BackWoodsBob

Would seriously be my hero at least!

Also subbed, because Bob will eventually need electrical help, and he'll text me for it, so I need to be ready.

If anyone's having problems with the stock ignition coils, and doesn't realize that the stock ignitor is just a transistor array that switches the ground of the individual coils, this sentence might help you.

[icingdeath88]

Originally Posted by BRZCory

Also subbed, because Bob will eventually need electrical help, and he'll text me for it, so I need to be ready.

If anyone's having problems with the stock ignition coils, and doesn't realize that the stock ignitor is just a transistor array that switches the ground of the individual coils, this sentence might help you.

Yep, knowing how stuff works really helps a lot.

People have had problems with the stock ignitors due to not realizing the very short dwell times that need to be used with them, and how to figure out what dwell times should be used. I burned mine because the dwell time I had it set to at first was 6ms (tunerstudio default). Even the LS2 coils only need 4.5ms, and I believe I came across someone using a dwell of 2.3ms with the stock ignitor/coils without problems. Now that I know that, once I have everything running well on the LS2 coils, I plan to switch back to the stock ignition hardware and figure out settings that work for them, so others will be able to use them and not have to spring for the LS2 coils.

[Tireiron]

I'm swapping to the newer COP (coil on plug) coils from subaru that the 205, 255, and 257 use. All you need to do is wire in the connector for each coil pack, run a ground wire for each coil pack, and bypass the stock ignitor. The subaru new style COP can run up to 5ms dwell time (the gray ones). Also because of the design with a longer boot and a coil that does not extend into the cylinder head it eliminates the cracking issues the OEM SVX COP have.

[icingdeath88]

Originally Posted by Tireiron

I'm swapping to the newer COP (coil on plug) coils from subaru that the 205, 255, and 257 use. All you need to do is wire in the connector for each coil pack, run a ground wire for each coil pack, and bypass the stock ignitor. The subaru new style COP can run up to 5ms dwell time (the gray ones). Also because of the design with a longer boot and a coil that does not extend into the cylinder head it eliminates the cracking issues the OEM SVX COP have.

Do they fit well on the EG33? Got any pics? Or part numbers? That sounds like a great idea.

[icingdeath88]

So, an update on my progress:

My brother bought a 2013 GTI, so I have the 6-speed car hooked up to the MS so I can do testing/tuning whenever I have a little down-time, and I'm using my 97 to get around for the time being.

Nobody buy the cheap Ebay LS2 coils! Myself, and at least several others on the MSextra forums, have had terrible luck getting DOA coils. I bought a set of 6, and 3 of the 6 were bad out of the box.

So I bought a set of 8 used OEM GM ones instead. Plugged them in and tested them one by one, all good. (Should have done that with the first set). Tunerstudio has a way to test them, just plug them into a spark plug, whose body is grounded against the intake manifold or wherever you can see whether it's sparking from the inside of the car. This set of coils also came with brackets to hold the coils, which I might be able to modify to fit somehow. Or at least use as a template or something.

The syncing issues seem to be resolved - the dual VR board seems to have done the trick. Once it's running a bit better, I need to check whether it needs shunt resistors due to higher voltage of the signal at higher RPMs, but I'm not very comfortable revving it very high just yet.

I also bought a timing light to confirm the base timing. I need to redo it, since I disabled all the timing settings, but I forgot to disable idle advance, but even if the idle advance was on full, it was still off from the .msq someone posted on the msextra forums that I borrowed to start with by 11* retarded. So next time I have a chance to play with it, I'll confirm the base timing 100%, and post the .msq for reference.

The knock module for the megasquirt I installed might be usable with the stock knock sensors, but I'd like to make 100% sure, since those kind of need to be super reliable. So I think what I'll do is get the 3-wire Bosch p/n 0-261-231-008 wideband knock sensors the guys who developed the knock module used, and use that, then once I know it's working with those, I'll try it with the stockers. They're only $~50 each, and readily available. They are 3-wire (ground/shield/signal), which means that they ground at the MS, which is apparently important. The stockers are only 2-wire (signal/shield) and ground through the engine block. Also, I occasionally get a knock sensor code, so I'd rather use fresh knock sensors anyway, esp on the built engine.

I also am really regretting not wiring up the IRIS solenoid when I was making the break-out-board, since I'll need to open it up to do that.

So, basically, I just need to buy a wideband O2 (or a pair ) and the bosch knock sensors, and wire them up and I should be ready to start the actual tuning part. I have just bought a trans for the '97 since the front diff is blown, and the trans has been on its last leg for a while, so car project funds are a little short right now. I might not be so patient, and just order the knock sensors and try and start tuning it with the stock narrowband O2 sensors, since they are wired up, and now that it's actually firing on all 6 cylinders they have been giving reasonable values.

I also seem to have found closed-loop IACV settings that work well, though I can't take complete credit, as the settings in the .msq I used as a base were a very good start.

Good news for those with OBD2 SVXes that want to use a megasquirt as well . I bought an OBDII body harness to OBDI ECU adapter from TomsSVX a while back. Using that, and FSM wiring diagrams/pinouts, I made an excel sheet documenting the wiring of the adapter , and making a pinout of the OBD2 ECU, cross-referenced to the OBD1 pinout as well. I also think I have the differences between the OBD1 and 2 TCUs documented in it as well. It needs just a bit more cleaning up and some verification before I'm ready to post it, but I will soon.

So, now that Tom pointed out the errors in the FSM OBD1 ecu pinout (the coil numbers were all mismatched), and I found a couple of others, it should be pretty straightforward to make a DIY BOB for the MS3X for the EG33, for the 92-95 SVXes. The OBD2 ones should also be doable if the proper ECU plug can be found. None of the DIYBOB ones are a match for it. But I think there are other Subarus from around the same time with a similar plug, so maybe the plug can be cannibalized from one of those. There are not very many OBD2 SVX ECUs around, so it's probably best not to cannibalize one of those for its plug, unless it's a dead ECU. I'll post a pic of what the plug looks like so others can keep an eye out for something similar as well.

Unfortunately, although the MS3 can communicate over the CAN protocol, it doesn't have full OBD2 support, so in states with inspections, you would still have to figure out a way around that. But with a DIYBOB, it might be possible to just plug the stock OBD2 ECU back in just to pass the inspection, if you set everything up with that in mind, and the car is still automatic (the OBD2 m/t swap CEL remains a problem).

I think the MS should also work fine with a stock automatic and TCU. If there is a lot of interest I might try it out with my '97. I plan on using the adapter I bought from Tom to make the '97 run on a 92 ECU and TCU, so I can use the ECUtune TCU and ECU software. The trans I got for the '97 is a 4.11, so I'd prefer to use the ECUtune TCU for that reason, in addition to the other benefits (higher redline and shift points, etc). So I could make a full BOB for the MS3 instead of the half-BOB/half-separate harness I am using in the '94, and plug the MS into the '97 to give it a try. Then probably sell the BOB. But that is not going to happen for quite some time.

I took some pics of the mess of wiring that is the engine bay, but they're on my home computer, so I'll post those later as well.

Also need to buy a car adapter for my laptop so my laptop won't keep dying on me when I've got it plugged into the car...

[92 SVX]

Power inverter 400w plugs into power point on car has 2 a.c.outlets and a usb.
Pick up at Wal-Mart 50 or so

[icingdeath88]

Originally Posted by 92 SVX

Power inverter 400w plugs into power point on car has 2 a.c.outlets and a usb.
Pick up at Wal-Mart 50 or so

Too late, just ordered one of these: http://www.amazon.com/gp/product/B002UI2Y8Q/

Although I should get an inverter one of these days just because they do come in handy.

[TomsSVX]

not trying to step on the progress I know how hard at work you are with this project. I know how projects like this can be a lot of fun and help you learn more than you ever bargained for. But I have to play the devils advocate here. Knowing what you know now and know full well all the time you had to put into this. Is all that time spent working on getting it running right worth it past putting down the extra cash up front for a plug and play alternative like the Hydra? No offense but to me, spending the extra $800 and saving months of frustration and having more time to drive and tune your car is worth the extra money.

Tom

[icingdeath88]

Originally Posted by TomsSVX

not trying to step on the progress I know how hard at work you are with this project. I know how projects like this can be a lot of fun and help you learn more than you ever bargained for. But I have to play the devils advocate here. Knowing what you know now and know full well all the time you had to put into this. Is all that time spent working on getting it running right worth it past putting down the extra cash up front for a plug and play alternative like the Hydra? No offense but to me, spending the extra $800 and saving months of frustration and having more time to drive and tune your car is worth the extra money.

Tom

Fair enough. For me, the learning, the fun of putting it together, and the problem solving aspect of it is half of the point. Saving the money is just a bonus for me. I have the time to spend working on it now, since I can't do very much actual mechanical stuff right now due to my current living arrangement. But I can build a wiring harness in my living room watching TV if I want. And at the end, I'll have a much better understanding of everything that's going on than someone who just plugged it in and fired it up. Also, "months of frustration" is far from the truth. I haven't spent that much time on it, I just don't have that much free time, what with grad school and everything else going on.

And when I'm done, all the hard work is done, and for the next guy to come along and try to do the same thing, it's just a matter of wiring it up. The actual assembly won't be significantly more difficult than merging harnesses, since it'll all be documented. Also, I'm trying to figure out ways to reduce the overall cost of everything, again, more for the next guy than for me. Right now, the total expense is probably not as far off from a Hydra as the initial cost of the ECU itself would indicate. I'll make a list to breakdown my cost so far, but it's closer to $1k than to $600.

I'm not entirely sure what all the Hydra can do, but I would be surprised if the Hydra could do more than the MS3X, especially since the MS community has a wealth of mods that can be built to make some really crazy setups possible. Did anyone mention yet that tunerstudio has an AFR-based autotune feature? I quickly looked through the specs on the Hydra website and I didn't really see anything that it has that the Megasquirt doesn't have that would benefit the EG33. The tiers are confusing also - how much would the one that works with the EG33 cost?

Also, nobody in Tampa AFAIK can tune a Hydra. Closest one IIRC is on the other side of Orlando.

[BackWoodsBob]

Good info, really gotta sit down and re-read it all!

The DIY PNP kits seem like the best bang per buck as far as standalone control goes, I mean, as long as you don't mind taking your time you save 800$+.

[icingdeath88]

Originally Posted by BackWoodsBob

Good info, really gotta sit down and re-read it all!

The DIY PNP kits seem like the best bang per buck as far as standalone control goes, I mean, as long as you don't mind taking your time you save 800$+.

Yea, those are a lot cheaper, but those use the MS2/Extra boards. You would have to go wasted-spark, and batch-fire with the injectors, unless you add another module for sequential injection. And a few other things aren't available as they are on the MS3/X, but not any that seem essential. Gotta make sure it can drive a 3-wire PWM IACV.

There will probably be some differences in wiring compared to mine, and some things will need to be figured out from scratch, as they are different from the MS3/X - knock control, etc. But it should work, and they are even cheaper. But you have to be able to build it.

[TomsSVX]

Originally Posted by icingdeath88

Fair enough. For me, the learning, the fun of putting it together, and the problem solving aspect of it is half of the point. Saving the money is just a bonus for me. I have the time to spend working on it now, since I can't do very much actual mechanical stuff right now due to my current living arrangement. But I can build a wiring harness in my living room watching TV if I want. And at the end, I'll have a much better understanding of everything that's going on than someone who just plugged it in and fired it up. Also, "months of frustration" is far from the truth. I haven't spent that much time on it, I just don't have that much free time, what with grad school and everything else going on.

And when I'm done, all the hard work is done, and for the next guy to come along and try to do the same thing, it's just a matter of wiring it up. The actual assembly won't be significantly more difficult than merging harnesses, since it'll all be documented. Also, I'm trying to figure out ways to reduce the overall cost of everything, again, more for the next guy than for me. Right now, the total expense is probably not as far off from a Hydra as the initial cost of the ECU itself would indicate. I'll make a list to breakdown my cost so far, but it's closer to $1k than to $600.

I'm not entirely sure what all the Hydra can do, but I would be surprised if the Hydra could do more than the MS3X, especially since the MS community has a wealth of mods that can be built to make some really crazy setups possible. Did anyone mention yet that tunerstudio has an AFR-based autotune feature? I quickly looked through the specs on the Hydra website and I didn't really see anything that it has that the Megasquirt doesn't have that would benefit the EG33. The tiers are confusing also - how much would the one that works with the EG33 cost?

Also, nobody in Tampa AFAIK can tune a Hydra. Closest one IIRC is on the other side of Orlando.

As long as the hydra has been set up to right it has an auto tune selection. But most people have found it easier to just tuned by ms. There is a lot about the hydra that most people don't know. Quite frankly if the MS3 could do all the things you can do with the hydra I would be blown away. I mean you can tune maps for antilag, individual cylinder fuel trim if your injectors are not perfect or if you intake and/or exhaust lengths are not equal. There is traction control, launch mode, valet mode.... The list goes on. Unfortunately since I am not really representing the hydra here anymore and Jonnybeas is an idiot so... If there were any real questions i guess I would be the one to ask.

Tom

[icingdeath88]

Originally Posted by TomsSVX

As long as the hydra has been set up to right it has an auto tune selection. But most people have found it easier to just tuned by ms. There is a lot about the hydra that most people don't know. Quite frankly if the MS3 could do all the things you can do with the hydra I would be blown away. I mean you can tune maps for antilag, individual cylinder fuel trim if your injectors are not perfect or if you intake and/or exhaust lengths are not equal. There is traction control, launch mode, valet mode.... The list goes on. Unfortunately since I am not really representing the hydra here anymore and Jonnybeas is an idiot so... If there were any real questions i guess I would be the one to ask.

The megasquirt can do individual cylinder fuel and spark trim, launch control, and I'm sure you could make another switch-activated map and call it valet mode. Traction control has been done by at least a few people. And I'm pretty sure it has anti-lag, but I haven't looked too closely at the boost-related stuff yet. Johnybeas being the only one who I know to get a Hydra from is another reason I didn't go that route. Although I'm sure I could have gotten one from another source if I really wanted to.

Actually, another advantage to the MS in my eyes is the community-support aspect of it. The guys who write the code and design the boards actually watch the support forums themselves, and sometimes will, for example, write a custom firmware for someone whose engine setup is a little out there.