VH45 Megasquirt setup....

[tmorgan4]

Even though I've already got the engine wired up on mine and everything appears to be working well (electrical wise) I've still got an interest in putting in a Megasquirt setup. For those of you not familiar with it, it's basically an adaptable ECU for pretty much any engine that would replace the stock ECU completely.

I think I've got basically the whole thing figured out and it would work extremely well with our engines. Especially for those running boosted setups and need the ability to tune the ECU. Megasquirt 1 allows fuel control, and Megasquirt 2 adds the ability to control spark (what I'd want).

It seems like a lot of people are hesitant to do this swap because of the wiring and electrical portion. It's an advanced engine with a lot of sensors. Using the Megasquirt system we could eliminate a lot of sensors, and essentially make it about a 10 wire hook up to your specific car. You can also get rid of your MAF since it uses a MAP sensor which would be a godsend for all the turbo'd people.

Anyone else interested in such a thing? The price compared to an aftermarket standalone is cheap.

[Hogg]

Im super interested, with boost in mind down the road as well I think it would be brillaint to have just a really simple VH45DE with simple computer and make mega power.

Really interested to see how things go along with megasquirt as Im rather new to "Home Brew ECMs"

-Spence

[tmorgan4]

I looked into a couple different setups over the past few hours and the price on them will really just depent on how many options people want in their ECU. Some of the higher end ones come with knock sensor inputs (even though our factory knock sensors don't do much), cooling fan relay outputs, and we could even keep the VTC even though I'm not sure how many people would want that.

I really like the idea of having a SIMPLE ecu with necessary sensors and not much else.

[Stinky]

I was looking into doing megasquirt for the vh at one point but the lack of coil on plug support was the killer. If they've released the router board or if MS2 actually supports the 8 coils I'd say go for it. It you cant do COP then I'd skip it.

[tmorgan4]

You can in fact keep the coil on plug setup. Of course it's the hardest setup to make work, but it will.

[darinz]

I think people get overly worried about the wiring. I have wired mine twice in 3 months!!!!!!!I have a pretty high end setup and all that was wired up is MAP, intake temp, water temp, cam and crank angle, TPS, VVT, obviously 8x injectors and 8x coils and then a fuel relay. That is pretty easy. The hardest part was getting the coil and injector timing correct depending on ecu requirements. ie some wire 1 to 8 others need to be wired in firing order.The advantages of an (good) aftermarket are well worth it. I don't know how reliable the Megasquirt but that is the biggest thing I'd be concerned with as if the ecu drops the tune then you can have a lot of issues. Also a cheap ecu that is hard to tune can end up costing a **** load when it comes to dyno time. The factory ecu can do it but it appears it will run the motor really rich so it will cost a lot to run and will mean bigger injectors are needed to get X hp.ie I have about 530hp (375 at the wheels) with standard injectors.

[tmorgan4]

Darinz...how did you wire up the coils with your Autronic ECU? Are you using factory coil packs on the spark plugs? Did you keep the factory ignitor chips?

[darinz]

I'm using an Autronic CDI and factory coils. The CDI replaces the ignitors so everything is controlled from inside the truck which was important for the wet mddy condition it is in. ie the motor may be running while under water. So I have the ignition wiring running from inside a sealed box inside the cab to the factory plugs, on the factory coils. The ecu can only run 4 coils so it is using a wasted spark setup.

[Carl H]

megasquirt is an inferior system compared to the stock eccs control module...the nissan efi is advanced by today's standards.i would go with the nistune software and an eprom emulator for tuning, from then on out its all gravy.

[qsiguy]

I think I have to agree with Carl. The more I learn about tuning my OEM ECU the more I like it. It has so many options and endless settings once you figure out what they all are, which I haven't. I am getting my tune working pretty nicely now. The only thing I wish I had at this point is an emulator so I didn't have to swap chips to try a new tune.

[Jeff Taylor]

I have been doing research on running the MS on the VH for the past week or so as well...

Here are my concerns:

Coil On Plug - Basic MS has one or two ignition drivers. MS Extra provides 4 or so ignition drivers, so 8 coils could be driven with a waste-spark setup. I'm not a fan of waste-spark, but oh well, it would work.

Injector Drivers - I'm under the impression that the MS does not have more than 2 seperate injector drivers? Perhaps I'm wrong? If so, injectors would have to be grouped into batch groups of 4, and fired simulatenously four at a time. While this doesn't matter too much at higher rpms, attempting to idle extremely large injectors may be problematic.

Nissan Cam Angle Sensor - My biggest concern. The Nissan CAS is very strange by design. It is an optical sensor with two seperate signal outputs. One output has 1-degree of resolution, the other has 45-degree resolution (on a V8 engine). Due to neither of these signals having a Top Dead Center reference the MS can easily acknowledge, special software or hardware would have to be designed to "decode" the signals from the Nissan CAS in order for the MS to function.

There has been talk of implementing a counter/decoder circuit on the incomming CAS signal prior to it entering the MS, however I am not sure I want to go through the bother.

I have also toyed with the idea of converting an AEM EMS honda box (because they're cheaper) or skyline/300zx box (because their ECU plug is the same) to run the VH45. This would work, but I don't want to spend the money on the skyline/300zx EMS nor risk converting the Honda 30-1020, 1040, etc and have it not work.

Anyway....There are several solutions, they just require either lots of time or lots of money.

[John Dixon]

Coil On Plug - Basic MS has one or two ignition drivers. MS Extra provides 4 or so ignition drivers, so 8 coils could be driven with a waste-spark setup. I'm not a fan of waste-spark, but oh well, it would work.

Nissan Cam Angle Sensor - My biggest concern. The Nissan CAS is very strange by design. It is an optical sensor with two seperate signal outputs. One output has 1-degree of resolution, the other has 45-degree resolution (on a V8 engine). Due to neither of these signals having a Top Dead Center reference the MS can easily acknowledge, special software or hardware would have to be designed to "decode" the signals from the Nissan CAS in order for the MS to function.

YOu can run wasted spark easily by just pairing up the inputs on the factory ignitors, keeps the wiring neat too as you can use the factory sub-looms inside the covers then just wire to the ignitor inputs.

For the CAS, I made up a new trigger disk with a ford 36-1 pattern to suit my Emerald ECU. Have spun it up at cranking speed and with a drill and the ECU reads the speed perfectly, no reason to believe it shouldn't work at high RPM too. Picture of the disk here: http://www.photobox.co.uk/album/7989055

[tmorgan4]

John....

From what I've seen in your pictures, you had a whole new crankshaft pulley made to replace the harmonic balancer. Did you incorporate this wheel into the new pulley?

I'm assuming it was custom made for the belt setup since you aren't running the factory accessories and you've got a dry sump system to turn.

[John Dixon]

No, I made a new trigger disk to fit inside the CAS. Better than a crank pickup as you can run sequential injection without an additional phase sensor on the cam.Also, using the CAS gives you a good 0/+12v logic level signal rather than a low level one off a pickup so much less prone to inteference.If you look at that pic you can see the new disk against the nissan one. The index (missing hole) is set 90deg BTDC on cyl no 1 (I think!!, still need to hook up a timing light and test it).

[Carl H]

i still vote for the stock ecu, ive got my rb20 mapped for a solid 22psi out of a gt30r and when it hits full boost it follows fuel and timing like a dream, not to mention full factory driveability and functions.aem ems is nice but tends to not play well with the stock cas and a new trigger disc is requires.some one a while back made a very comprehensive post about the stock cas and how it worked with the ecu but in essence its a very high resolution sensor with 2 dedicated processors for decoding and figuring out what to do with the signal and one main processor for subroutines and other functions.impressive stuff really, again like i said very advanced.

[SSDwellah]

i still vote for the stock ecu, ive got my rb20 mapped for a solid 22psi out of a gt30r and when it hits full boost it follows fuel and timing like a dream, not to mention full factory driveability and functions.aem ems is nice but tends to not play well with the stock cas and a new trigger disc is requires.some one a while back made a very comprehensive post about the stock cas and how it worked with the ecu but in essence its a very high resolution sensor with 2 dedicated processors for decoding and figuring out what to do with the signal and one main processor for subroutines and other functions.impressive stuff really, again like i said very advanced.

Regarding the CAS problems with the AEM EMS, have you heard about switching the trigger from falling edge to rising edge? That seems to fix all of the Nissan RB CAS sync problems (by the way I think there were two parts: one mitsubishi and one hitachi, and only one of them suffers from this symptom). There is a whole thread about this on the AEM electronics forum. My apologies if you've already tried that and still have issues.

[darinz]

My ecu came with a replacement disc for inside the VH CAS sensor. It is similar to one on the right in the link above, but it has less segments. All I can say is my motor runs very very smoothly at all rev points and never hesitates, misfires etc. Apart from when you lift off as we didn't tune the deceleration maps as who worries about a few small backfires when braking!!!!!!!!

[s2k12]

Has anyone used MSII on a VH yet?

[Mettler]

megasquirt is an inferior system compared to the stock eccs control module...the nissan efi is advanced by today's standards.i would go with the nistune software and an eprom emulator for tuning, from then on out its all gravy.

QFT! Huge functionality in the stock unit! Very impressive.

If I had but one complaint about the factory eeprom, is the 16x16 resolution fuel map... but really, who needs to make finer adjustments than every 4-500rpm increments anyway?

From what I've seen, and I haven't gone very far into it, tuning the AFRs is a breeze.

What software are you guys using to edit the actual bins? And also, is anyone making any headway in terms of expanding the ADR file and finding more functions hidden away in the hex table?

[tmorgan4]

What I'm really curious about is if someone can modify the ECU so it doesn't throw an EGR temp sensor, automatic transmission, or speed sensor signal code so my check engine light isn't always lit up. I'll never know if there's an issue since it's lit up all the time.

[Marquinho]

I thought this thread was about who was interested in running Megasquirt!!! But it seems that people have decided to make it otherwise.

So, I'm interested!

And let's be honest, for all its high-tech ECU, the stock unit just complicates matter for me. Honestly guys, I'm doing an engine swap, not trying to run a luxury car here. The less stupid sensors I have to deal with the better for me - I want to be able to tune the engine for power and drivability, mostly timing and fuel maps while controlling knock and keeping it safe. cam timing is ok, but I prefer to remove it all together if possible.

[Mettler]

And let's be honest, for all its high-tech ECU, the stock unit just complicates matter for me. Honestly guys, I'm doing an engine swap, not trying to run a luxury car here.

? The stock ECU runs the engine only. The rest of the Q45's electronic features are taken care of by other individual & isolated computers. The engine computer is just that, the engine computer, and I'm not sure how this complicates matters?

The less stupid sensors I have to deal with the better for me - I want to be able to tune the engine for power and drivability, mostly timing and fuel maps while controlling knock and keeping it safe. cam timing is ok, but I prefer to remove it all together if possible.

These stupid sensors exist to make the engine run properly! If it's an advanced EFI motor, it's guaranteed to have sensors all over it. Exactly what sensors would you actually want to remove? Temperature sensors? Or perhaps the oil pressure sender unit? Or maybe the AFM. They're all needed!

Also, the VTC improves the engine's powerband and thus is a desirable feature. Why would you want to remove it?

[Marquinho]

? The stock ECU runs the engine only. The rest of the Q45's electronic features are taken care of by other individual & isolated computers. The engine computer is just that, the engine computer, and I'm not sure how this complicates matters?

These stupid sensors exist to make the engine run properly! If it's an advanced EFI motor, it's guaranteed to have sensors all over it. Exactly what sensors would you actually want to remove? Temperature sensors? Or perhaps the oil pressure sender unit? Or maybe the AFM. They're all needed!

Also, the VTC improves the engine's powerband and thus is a desirable feature. Why would you want to remove it?

I've built my share of performance engines and know perfectly well what the stock ECU does, but thank you for the lesson...

Since I don't really like to type much (which is the reason I only have 34 posts although I've been a member since 2004), you can see an example of the engine builds I've done before (in case you doubt me, which people tend to do) here:

http://pages.sbcglobal.net/marcoy/

So, when I say that I don't want deal with stupid sensors, I know fully well what I'm saying and I stand by my philosophy of building my engines and cars; lightweight and simple.

Honestly, I was just making a point – why is it so difficult for people to respect the topic. If you’re interested in running MS in your VH, say so. If you’re not, then move on. Some of us don’t mind having a “lesser” ECU running our cars. We’re not stupid, we can ask questions when in doubt.

[npez]

? The stock ECU runs the engine only. The rest of the Q45's electronic features are taken care of by other individual & isolated computers. The engine computer is just that, the engine computer, and I'm not sure how this complicates matters?

These stupid sensors exist to make the engine run properly! If it's an advanced EFI motor, it's guaranteed to have sensors all over it. Exactly what sensors would you actually want to remove? Temperature sensors? Or perhaps the oil pressure sender unit? Or maybe the AFM. They're all needed!

Also, the VTC improves the engine's powerband and thus is a desirable feature. Why would you want to remove it?

I'm in full agreement with mettler and the others regarding the sophistication of the factory ECU. When you begin to make "compromises" (waste spark setup, no VTC, swapping CAS trigger wheels, etc.) to accomodate the engine's operational design, there is something already wrong. An engine computer shouldn't be "made to work" with the engine, it should fully accomodate it from the get-go. I don't believe Nissan spent millions in the development of the ECU if they didn't have to. There are options to tune the factory ECU, and the hardware/software probably costs as little as having to purchase a MS2+. Now if you're doing this as an academic exercise that it can be done/you made it work, now that's a different story altogether.

Mettler a possible correction (correct me if I'm wrong) but if I recall correctly while looking at the VH electrical diagrams during my Z32/VH45 electrical integration document, I believe the oil pressure sender is not a sending unit for the ecm, but is wired to a low-pressure "dummy light" on the cluster (this can be seen as the sensor is only 1 wire, hence no reference voltage/feedback loop to the ECM). I may be wrong but that's how I remember it.....

Thanks,Nick.

[Mettler]

Yeh you're probably right... I was just sitting here trying think up 'sensors' that could actually be removed... of which there are SFA really.

Cam angle sensor - necessaryTemp sensor - necessaryKnock sensors - useful for tuning, so necessaryetc etc...

I can't really think of anything you'd wanna remove that isn't useful if you still want to run EFI, apart from the EGR emissions stuff.

About the only real thing you could do is remove the TPS and the AFM, and switch to MAP... which doesn't necessarily reduce the complexity of the setup.

Marquinho excuse me if I came across the wrong way, that was not my intention, I'm just trying to understand what you mean... the VH electronics are fairly simple already! Anyway, sorry for the derailment, back to megasquirt!

[tmorgan4]

I'm responsible for derailing my own thread.

I was interested in the Megasquirt setup when I started this but I've since realized that the factory ECU is great for what I need.

[qsiguy]

Jeff Taylor told me he got rid of the stock ECU when he couldn't get the Ostrich 2 working. He went with an AEM EMS, a "Honda 1010 box". Not sure what this is exactly but it was far from a "plug and play" operation from his description. He does now have wasted spark ignition. I believe his primary motivation was to have the real time tuning option.

[elwesso]

For some it may be 6- half dozen of another to get these aftermarket systems to work. IMO, the time you spend wiring up an aftermarket system and making it work as well as the STOCK computer could be used to simply LEARN make the existing system work better.. Even if you want to convert to an MAP they make converters that do that, and its still cheaper than most GOOD aftermarket ECU.

Nistune and their emulator basically do the tuning for you, making the stock ECU very versatile and easy to program. What really turns me on about the stock ECU is the ignition control. If I were running a motor with a distributor setup, i might be a bit more inclined to use something like the MS setup. In the old BMW world the MS setup is very popular because its nearly plug and play, and gets rid of the archaic AFM that comes on the cars.

Something I'd like to do that would really make it possible to tune without a dyno is somehow rig up a light to the knock sensors so we know when detonation is occuring (because we hear it FAR after its actually started).. that way, you simply tune your AF based one your wideband, and keep bumping timing until the light comes on, then bump it back.

[npez]

Elwesso,

This may help you out: " TARGET="_blank">http://tunertools.com/articles...ons

Thanks,Nick.

[elwesso]

youd think thered be an easier way since the factory gives us a knock sensor that works pretty well.. some way to tap into the signal..

good question for Q45tech would be to analyze how the KS reacts during engine knock. We know how to test if theyre good or bad, now how to determine when the ECU "knows" the motor is knocking or not.