Vertigo

+1 for wrinkle paint. Looks good.

Worked beautifully

Ive decided that dealing with four IGF lines and a 5v supply wire and a second transistor stage is just too finicky to bother with. Im sure it would work, but Ive decided to go the route of the Megasquirts own tach output function - just need to solder a wire into the board. Last night I tested the original circuit in the first post with a square wave function generator output of my oscilloscope, and it works flawlessly - tach responded to frequency tweaks from 10hz to 200hz @ 10% duty cycle (actually, up to 50% duty cycle was fine also, and Im sure 90% would work too, but I prefer pulses to be as short as possible). Above 200hz, the tach wanted to go way out of bounds. Tonight I finish the board modification and test with the car running.

I have redesigned the circuit with a second stage, though I am not sure exactly how to separate the two 5v lines - Ive put resistors in as a guess, but this isnt really my forte. Can you advise? The rest of the circuit should be sound. Added some waveforms and helper indicators in red and blue, and wires with grounds in grey overlay. Here is going high: And going low... Edit: Actually, the spike is triggered on voltage going high, not low, because its there that current flow drops to near zero. But thats just the diagram indicated incorrectly. The circuit remains valid.

Sup guys. Ive built the following circuit to translate what I thought was a 5v pull-high square wave tach signal into the signal that the AW11 tachometer requires, originally derived from the -ve of the ignition coil - 12v pull-low square wave + voltage spike. The idea is that the tach sees 12v most of the time, then when the transistor is closed briefly, it sees 0v and the inductor is charged. When it opens again, the tach sees 12v again, the field in the inductor collapses from lack of current, and spikes a voltage. This gives the correct signal to the tach. It doesnt work, because the output from my coils IGF line is actually 5v pull-high square wave instead - I needed to have 5v supplied to the IGF line, where the coils switch it to ground. I can make this change easily enough, but that means that the output signal will be inverted to pull-high instead, so I attempted to modify the above circuit. See below: Ill admit, this is a guess. I have adjusted the transistor trigger appropriately, but Im unsure about the 12v side. Need to connect the tach output to the inductor, but seems to me that the inductor will still need a fairly free flowing path to charge it, which is now missing. Any ideas here? The other option I guess I could do is to invert the inversion with a second transistor stage, but that seems over the top.

Absolutely is. When it works, its really awesome. Its a bit more sensitive to environmental variables than other ECU's, but you can compensate for that most times. Actually, I just got the COP's running last night - big win. No need to test with a Link now. Turns out that the biggest problem was that I had double-crossed the ignition trigger lines, so it was ordering spark (from ECU to loom to coils): 1-2-3-4 -> 1-3-4-2 -> 1-4-2-3, and thats because of an incorrect pinout diagram I found online. Always do a bench test and directly observe your sparks to be sure they are in the right order!

Another option would be to plug in a Link Atom G4+ of someone elses, see if it runs any better. Because I used a Link loom, itll plug right in, just need to tweak settings slightly.

Yes, sadly the MS1 (or maybe its the firmware its running) does not support modifying the waveform detection settings on the primary trigger input - only the secondary one, if it exists (which it doesnt in my case). Swapping the VR wires results in invalid RPM reading, so pretty sure Ive got things the right way around. My VR lines are well shielded, but I will try a bit extra to be sure. Im leaning towards the VR conditioner on the board being incorrectly set, but open to other ideas.

Hey guys. I bought a Megasquirt from MSNZ many years back now. Its an MS1 v2.2. It read my 4-tooth distributor sensor no problem and ran really well that way, but has always had issues when I attempted to read a 24-tooth CAS sensor modified with one tooth missing (for #1 TDC reference). Spinning it with a drill, it reads a very good an solid RPM, but the detected triggers are often all over the place - sometimes detected, sometimes not, and sometimes false triggers detected out of order. Im going to go back to MSNZ and get an answer for this, but Id like to hear what experiences anyone here has had with their unit - from the same company, or sourced from overseas. Also let me know what version of MS you have.

Oops, thanks!

Hi guys. Just after some general chat around the cert process, how hard it is, your experiences, etc. My MR2 has aftermarket seats, wheels, suspension (adjustable), engine (20v currently, soon to be 16v turbo for the cert), and brakes (slightly bigger from another Toyota). The seats are Bride Lomax, with rails to suit from NZKW. Im hoping these will pass inspection. Advice here would be nice! The engine that will be certed will be a 16v 4AGZE with supercharger swapped for turbo. Im guessing so long as things are tidy and leak free, it should pass fine. Is bracing for the turbo a requirement? I have an oil filter relocation, will this be focused on? The fuel system is mostly stock, with an aftermarket FPR as the only modification, though I do intend to upgrade the fuel pump too at some point. The suspension is adjustable, but a decent brand (Yellowspeed I think). Nothing really special about it, just a tiny sliver of negative camber, and fairly stiff. Been told these will probably not be a problem. Wheels, so long as they arent bigger diameter, you can go as wide as you want, it seems, which is good because mine are 20mm wider than factory. They are hidden under arch extensions. Obviously Im intending to visit the certifier soon to have an initial once over for advice from them, but was curious what you all thought as well.

Hey dude, long time no see. Good to see you still doing the expensive car toy things. Been bitten myself - got two AW11 MR2's now, with one donating its 4AGE turbo to the daily soon. Be cool to catch up some time. -Cam

Thanks dude. Im going to rewire the entire loom, so good opportunity to switch at the same time. Good info.

Oh wow, what a great idea - using the cam wheel teeth themselves! With another for cylinder ID. I love how its recessed behind the plate. Im not using the cam plate right now, but I may if this is a good option. Thanks! Where did you source your hall effect sensors from?

Hi guys. Ever since I bought my Megasquirt, Ive had issues straitening the ignition system out, which is a stock dizzy. Im feeding it the 4 tooth sensor signal, with 5 degrees of trigger angle, and it seems to work most of the time, but every so often it spazzes out completely, and sometimes doesnt start up. I have a coil on plug setup ready to go, but its using a CAS withe VR sensors (with one tooth ground off, so its 24-1). Im tired of the headaches that come with VR sensors, and have yet to start up with the COPs, and would rather have a hall sensor instead. Can anyone recommend a sensor that would be ideal for this task? It would need to sit inside the CAS in place of the VR sensor.

Rather than clutter the internet, Im consolidating my build threads to a single forum on mr2.org.nz. Would you like to know more?

I have two AW11 MR2's - one turned into a mule, and the other is my daily. This thread is about how one turned into the other. The project started seven years ago, when I bought a silver AW11. It was tidy enough, but had a bad engine that kept overheating. I attended a Toyspeed meet in '11 down in Manfield, and after the journey there, doing a few laps of the track, and the journey back again, and having to put up with blowing coolant everywhere every so often, I had had enough, and arranged to buy a 4AGZE smallport, with the intent to rebuild it over a summer and within a year of that, throw a turbo on it. It would be my first engine build to be completed, though I had practiced a few times with various 4AGE's that never made it to completion. Summer arrived and departed, and the engine was in pieces. Money and time were the issues, but I kept at it, gradually acquiring parts, planning etc. I realized this would take a lot longer than I figured, so a year later, I swapped the overheating 1st gen bigport out for a 2nd gen bigport, which was a supreme workhorse and lasted the next four years without any problems. Progress continued on the 4AGTE build as time and money allowed, but was interrupted for a few years, and stored at my brothers workshop. At this point it was an assembled short block and reconditioned head with bigport cams. Financials improved in 2015, and my brother was moving, so I arranged to pick up the engine, and immediately I got the itch again. Within a week or so, the head was torqued down on the block, timing belt set, and turbo slung on the side. It should be noted that the turbo at this point was a T3 flanged China special with a stainless steel manifold that was highly likely to bend. But its what I had. I had some oil and water lines made up, and then started planning the supporting mods. * Adjustable rising rate FPR * 440cc 7MGTE injectors * MTX-L wideband gauge * Megasquirt * Celica W2A intercooler, radiator, pumps, and hoses suitable for an MR2 * DPR blowoff valve * 2.5in twin-outlet exhaust with 20v headers At first I tried using the dual coil packs and CAS that came it, using a Mitsi dumb ignitor with the Megasquirt. The intent was to get this I didnt have much luck getting it to run, so tried a coil-on-plug setup, with the Megasquirt set up for sequential ignition. This also proved hard to perfect, so while I havent given up on it, I figured the distributor based system that was in the car was good enough for now. And it ran, and I was getting bored with ignition. The engine itself is mostly stock. It was bored over 0.5mm, acid dipped, crack tested, shot peened, fully balanced, align bored, skimmed, the works. I wanted this thing to be bulletproof. I fitted brand new factory forged pistons and ACL Race Series bearings to the block. The head was reconditioned to factory specs, but with some slightly bigger bigport cams that I had lying around. I fitted some adjustable cam gears, a Cometic MLS head gasket, and ARP head studs and flywheel bolts. Soon enough, there was nothing left to do, so it went in. And fired up. And it was glorious. The engine that I built from scratch was living and breathing. Its now done about 5000km, and hasnt missed a beat - its been a huge success. Im so happy that nothing has gone wrong with it.. because any kind of engine failure would probably kill the project, and it proves I did everything right. If Im honest, I had reservations that the engine wouldnt destroy itself as it sat there about to be fired up for the first time. But no, its proven to be a perfect runner. Around 8.5:1 compression, 160psi on all cylinders. As I was having issues getting the Megasquirt running well, due to dodgy grounds, mostly, I ran it on the stock ECU for the past couple of years. I attempted to mount the turbo (venting to atmosphere), and had a return bung welded to the sump, but it was too restrictive and resulted in smoke billowing out of the exhaust. Its possible I could have fixed things by just using a much bigger oil drain, but I decided to go down a different route. A year ago, it failed a WOF for structural rust, and when I went hunting for the worst of it, discovered most of the front firewall was being eaten away. I figured I could sink money into it in an attempt to revive the car, or find a pristine AW11 instead. Well, I found one. It has been completely de-rusted, a top quality paint job applied (dont care about color so much), 205-wide 5-spoke deep dish wheels, wheel arches, adjustable suspension, Bride bucket seats, braided brake lines, and (the finishing touch) a Silvertop 20v with open throttle bodies and a Blacktop ECU. Pretty much everything I wanted in an MR2 that I hadnt already done to the silver car. I snapped it up in a heart beat. So the project officially is now the yellow car, and the silver car is deregistered, but still in use as my test-bed. It still holds the rebuilt smallport as its heart, for now, but that will be swapped into the yellow car in the near future. Earlier last year, I found a good turbo setup, previously used on a race spec Corolla. It had a wicked low profile tubular manifold that sat the turbo, a TD05HR, quite high, which is exactly what I was after. Unfortunately, when attempting to fit the thing, I discovered that while it bolted on ok, the inlet to the turbo was blocked by all of the AW11 gearbox linkages, making any attempt to use an air filter impossible. I sold that turbo and manifold for what I bought it for, and considered going back to the original turbo, and sourcing a scavenge pump to solve the smoking, but then as luck would have it, while bitching about this situation on the MR2OC forum, one of the members had the solution - again, a TD05HR, but this time with a manifold designs specifically for AW11 MR2's. The manifold sits the turbo slightly skewed, and so clears everything it needs to, and the inlet is freely accessible. Bought it immediately. Test fit, no problems. Went ahead and started planning a foolproof oil drain for this unit. Took the sump off and drilled out a hole for a large brass fitting, sealed on both sides, and had the turbo outlet bung modified with a -12AN full flow bung, and a matching AN-to-hose barb fitting. Initially I wanted to see what the oil was doing, so am using a length of transparent hose entirely unsuitable for the application, but its serving its purpose. Itll be replaced with something more suitable for heat and oil very soon. Also had exhaust downpipe and turbo uppipe sections made, and finalized the rest of the intake charge piping, intercooler hoses, wiring, etcetc. Just recently, I managed to fix the remaining issues the Megasquirt was having, and got it running well, so there wasnt much left holding me back from going for the first run with the turbo. No smoke! Despite having a guesstimate tune (rich and retarded), and an exhaust leak at the manifold, it boosted for the first time up to 5psi. Great power delivery, though a little late in the game - guessing its due to the aforementioned exhaust leak, and possibly boost leaks. Also probably the tune. Everything can be improved upon from here. So thats where the project is at for the time being. More to come. The ultimate goal is 15psi and near-enough 200kw.