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monster turbo3 build
Topic Started: Jun 17 2011, 05:53 AM (36,530 Views)
Jittney
Anchorage 92 XFi

Looks sharp, t3ragtop.
Interesting reading the fine print, too :news
Megasquirt does sound like a wonderful thing.
I've never seen one.
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t3ragtop
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Turbo3 and Twincam Tweaker

megasquirt is a diy engine management system that runs open source code. i built this one in my basement one winter. this particular megasquirt is an ms2 that i have customized for 3 direct channels of ignition using 3 separate, outboard ignitors driving 3 individual coil on plug coils from a ford 5.0 liter v8. i used a jbperf 4 channel adapter board populated with only 3 injector driver fets. i used the adapter board's db15 connector to feed the direct drive signals for the coil ignitors from the ms2's main board.
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i also have an onboard usb to serial converter board that lets me do the communication between the controller and my supervisory netbook using a mini usb/ usb cable. i've been doing some other advanced circuit modification on the main board, reducing it's component density by getting rid of the rudimentary signal conditioning circuits. i devised some nifty hall effect type sensors and outboard signal conditioning boards that output super clean signals directly to pins on the megasquirt's processor. that has allowed me to run a perfect timing signal (ie no false triggers, no change in amplitude vs frequency) up to 19,800 rpm (the unloaded speed of the dual shaft grinder motor i use for metal polishing.) that's a little better than twice my maximum engine rpm so it should work fine. here is a pic of the signal conditioner boards for the crank and cam hall effect device sensors.
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the mega squirt with my bleeding edge timing sensors gives me digital precision with a resolution of 2.5 degrees of crank rotation (using a 36-1 tooth trigger wheel off of a ford aerostar's v6 engine.)

i'm running a secondary timing sensor using a hall effect device to detect a magnet embedded in the adjustable cam gear. that lets me send a positional signal to the controller to let the counters know when the cam is at it's zero position to properly sequence the camshaft phase (crank turns twice for every single revolution of the cam and the controller needs to know when the intake valves are open and closed.)
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engine management gets pretty involved but i did electronic industrial process control stuff for 30 years or so. after i got up on the learning curve with the megasquirt and it's tuning application options i started to see what was going on. :D

honestly, the controls are so flexible that i had the hardest time deciding exactly which features i needed to select and build for. i started out with 3 coils and batch fire injection and almost immediately ditched that original build for sequential injection on the blue monster turbo3. this black engine gets pretty much the same control set but fewer secondary features - no water to air intercooler pump and fan outputs and less elaborate boost controls.
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snowfish
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Basic GearHead

Can't wait for the day this baby is spooled up! :popcorn :nfs Going to be incredible! :rocker
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evmetro


How much torque can one of those clutches take? I want to try running a clutch on my next ev build, but I am really worried about its ability to take a lot of torque. This hotrod you are building looks like it will be needing the heavy duty clutch...
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94RHDRollerskate
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Forum Stud Muffin

.
My car (and I) dream of a t3ragtop power plant under the hood. Mega drool factor! Are you keeping tabs of a build cost, so that when I score with the Powerball, I know what to plan for?

.
Edited by 94RHDRollerskate, Dec 19 2012, 12:17 AM.
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t3ragtop
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Turbo3 and Twincam Tweaker

ev, the turbo3 has a torque curve that builds as the turbo spools up so the application of torque is relatively controlled. the stock g10t uses the same clutch pack as a suzuki twincam engine.

you could probably use a stage2 clutch set for a twincam on your 'lectric car. i realize that the application of torque is even more visceral with an electric drive. since the controls are so different (torque goes to zero off throttle with 'lectric drive) you probably wouldn't even need a mechanical clutch to shift gears.

the 'lectric car i built in 94 was on a saab sonett chassis and it's transmission used an over running clutch (free wheeling) on the transmission's input shaft. when there was no torque applied, the engine (or motor) was disengaged and the car just coasted until the engine's rpm matched road speed or the engine's rpm exceeded road speed at which point the over running clutch engaged and re-established power transfer from the engine to the wheels.

rollerskate, i have kept all the receipts from both the blue monster and the lil' black monster builds. suffice it to say that financing the blue monster would have bought a pretty nice late model used car. the black engine so far has passed the 2 grand mark. that's why it takes me so long to build these. i save my lunch money up and buy a part. piece by piece, i end up with an engine. :D

engine management controls and wiring runs over $1000 all said and done (doing all the assembly, wiring, and installation yourself and using all new stuff.) depending on instrumentation and the supervisory laptop you use it can go as high as twice that amount. the lil' black turbo3 will be a pared down version of the blue monster - 153 hp max, conventional air to air intercooling, and minimal instrumentation. i can share the supervisory laptop between my two cars, use the same tuning sofware, etc. and that will save me money.

you need to factor in the cost of chassis preparation, too. you wouldn't want to just plop engines like these into a base model metro. you need suspension and brake mods that will handle the increased engine output. 100+ mph with 12" wheels and base model brakes would definitely put brown stains in your skivvies. :D
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evmetro


Have you been able to find any tricks to connect to the road better on an "aggresive" take off? The verts look like they may be even lighter than the models that I build, so I am guessing that you are experiencing the same lack of traction problems...
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Jezza
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Boost Junkie

Havent been around for a while but I especially had to search for this thread. Great work as usual...

Booooooost!!!
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t3ragtop
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Turbo3 and Twincam Tweaker

this engine is on the back burner, still on the bench where it has been for over a year.

i have had bigger fish to fry. :D
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Freeman
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The Family Man

I liked this, well, most of it. Air to water intercoolers suck. Just my opinion. I don't like the weight or the heat soak aspect for time attack racing. But the rest of it is interesting. I didn't see any dyno graphs. This is all theory? Are you going to do the tuning yourself? I have no experience with megasquirt outside of J-series Honda motors (V6s). I know it is a lot more wiring than what I usually use to do tuning though. 150 HP is such a weird number to me. I want more power. You're using a TD04-ish turbo? I'm not the most knowledgable turbo guy out there, I can admit that. But it seems like it's a small T25 turbo or something. Is there a company that offers forged internals for the Geo motors? Or is that the reason you went with the stock turbo block, because it is stronger? I wonder so much about this whole thing. The page where you were talking about high oil pressure leaving the oil in the head and starving the block, that blew my mind. I guess I'm use to 9,000 rpm and high oil pressure. What fuel pressure do you run? Stock is like 20-something, right? I forget the CFM calcs for boosted HP, but you mentioned 220-ish HP being the limits of your turbo. Which seems accurate if I am understanding the turbo correctly. I don't know what the curb weight of your car is, but I bet 150 Hp still feels pretty peppy. Had you mentioned an oil cooler? May be a good investment. I think you did, or someone did. I just scrolled through a page and saw Vitara! Nice! I've definitely see my fair share of vitara internals on a SOHC motor before. 4 cylinders, but none the less. What is the compression ratio on this motor? I know a lower compression makes it easier to tune, or more forgiving at least. But higher compression helps with spool speed and out of boost performance. Not sure how either of these relate to fuel economy. I can ooh and ah all day. I'll be back around and maybe we can chat about something.
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t3ragtop
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Turbo3 and Twincam Tweaker

first off, this thread shows the blue turbo3 engine and a second turbo3 engine, the black one towards the thread's end.

the first one, the blue engine uses factory stock engine internals from the g10t turbo3. i had to replace bore liners to get back to where the bores could be machined to fit the factory pistons and new rings. basically, the engine build was blueprinted to factory specs with the rotating assembly components weight matched and zero balanced and then the assembled crankshaft and components from the flywheel to the accessory pulley turned as a unit on a vibration analyzer.

one of the reasons i used a water to air intercooling system was to reduce heat soak. on an air to air intercooler, once the car is stopped, the air not available for cooling, the intercooler and charge air piping immediately start to heat up. the air to water system uses a circulation pump to pull heat out of the intercooler and move it to a heat exchanger up in the front where a fan maintains air flow to shed heat. the circ pump runs continuously and the heat exchanger fan is controlled via the megasquirt controller using coolant temperature to steer an analog output.

although the air to water intercooling system is a lot more involved with plumbing, pumps, and fans, it's also considerably better at consistantly maintaining nominal charge air temps. i can hold a solid 98* f intake air temp on a 90* f day from a stopped idle through wot runs. you cannot do that with an air to air intercooler.

the second, and maybe the biggest reason i did the air to water system was that jardamuth at turbine tech sort of challenged me to do it. :P

i have an oil cooler on the system. it was required to control engine heat. the thermal systems on this project were carefully considered and i use just about everything from insulating materials to dynamic systems that shed heat. at a normally aspirated output of 56 hp the g10 block isn't particularly challenged. bump that output up double or more and you have to start dealing with getting the heat out of the engine. i designed things with a 90 to 100 degree ambient which would represent the hottest days we get here in central ohio.

from a technical aspect, the biggest challenge of the project (aside from absorbing huge chunks of technical info from the megasquirt documentation) was developing a method of reading engine timing and controlling ignition events perfectly from idle to more than twice the event periodicity. the very last thing that the engine needs is to have the ignition "fart" at 9000 rpm and send a 21 psi enhanced piston through the block's wall. the guy who made the most headway with a high boost mk2 turbo3 just before i took up the mantle ended his development by blowing the front of the block out with a pretzeled connecting rod.

i interpreted that failure from his description of the event and the failure mode to be an ignition misfire at high rpm. one of the first things i took a look at after i had my blue engine running was ignition trigger and ignition event errors. i had set the injection up in batch fire mode with 3 channel coil triggers and ford cop ignition. i used the recommended variable reluctor sensor from the same ford engine i borrowed the trigger wheel from.

what happened was that when the engine was at idle, the signal level from the v/r sensor was very low (in the mV range.) when the engine speed went up, not only did the v/r sensor's signal frequency change, it's dc voltage went up. when things were dialed in for idle, the sensor voltage climbed to around 70 volts at 6500 rpm which was giving the megasquirt controller's signal conditioning fits. the controller was sending signals to trigger random ignition events at the wrong time. another problem i was having was in controlling the 450cc/min injectors at idle. i couldn't get them to open and close fast enough at idle to make the engine happy.

i developed a set of hall effect sensors and outboard signal conditioning that only measures frequency and maintains a 4.53 vdc output signal across the 0 to 20000 rpm range. it also sets up the controller for full sequential injection and spark control. the digital output from the sensor conditioning boards can be applied directly to the microprocessor's inputs which circumvents the need to use the onboard megasquirt signal conditioning. that allowed for stable spark events throughout the engine's speed range.

using the sequential injection mode also made it possible for my tuning application, tuner studio, to open up some previously grayed out menu options that allow very fine control of the injection sequencing. it gave me an adjustable fuel trim for each cylinder which allow me to correct fueling for the #2 cylinder which shares cooling jackets on either side with the #1 and #3 cylinders which has always been a problem for the g10t. i can ad a tiny amount of extra fuel to adjust the fire deck temperature in the #2 cylinder to help keep it from melting the ring lands- something that has occurred in turbo3 engines that were run at higher than factory boost pressures.

in sequential mode i can also tweak the injection event timing to move it so that the injection event beginning and ending points can be set to occur anywhere within the opening and closing of each cylinder's intake valves which allows me to deal with airflow latency in the ports and intake runners. air, having mass, doesn't start and stop immediately. it takes a short period of time to get air moving in the runners and ports. you want to inject fuel into a moving air stream so having the ability to delay the injection event until the air is moving to actually carry the fuel droplets is a nice feature.

i had some time in batch fire mode to do some tuning which is what pointed out deficiencies that needed to be corrected. i had some minimal tuning time while i researched the sequential mode and started rewiring the controls. since i've had everything ready to go back on the car i've played with a few other car projects including my red resto-rod vert build and haven't put any more time into the blue vert. this summer i plan on completing the mods and doing some tuning. i just want to roll the car to some local car shows, no competition events, and when i get the several hundreds of dollars i need to have the car tuned on a dyno i'll do that to get the final tune on it.

i also have a megasquirt control set built into a factory ecu case and wired to use the factory engine harness plus a small aux harness for the injectors and intake air temp for the twincam engine in my red vert that i want to install in the spring. i'll probably tackle that first before i get back to the blue vert.
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Freeman
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The Family Man

Despite realizing this was 2 different motors, I didn't seperate my questions. Seem like tuning is just hard on this platform. Too much of a pain for me, so props to you! Also, congrats on taking up a challenge. Have you tried to monitor the EGTs on this before? You are tuning individual fuel trims on cylinders, I'm not sure how you decided what was working and what was not. Unless you have 3 wideband O2 sensors or 3 EGT sensors. Preferably both for the tuning aspect. I'm going to look at the dimensions of the engine bay, but have you ever thought of using a non native motor in here?
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CAMI MAN
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CUSTODIAN OF THE MR.SUZUKI CONVERTIBLE

t3ragtop
May 21 2013, 08:25 PM
this engine is on the back burner, still on the bench where it has been for over a year.

i have had bigger fish to fry. :D
What is the bigger fish project :whistle
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Jordan


TurboEF
Dec 30 2013, 10:29 AM
I'm going to look at the dimensions of the engine bay, but have you ever thought of using a non native motor in here?
There are a number of people who have transplanted Honda motors into Metros/Swifts.

There's even people who have transplanted V6 and V8 drivetrains.
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Freeman
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The Family Man

Jordan
Dec 31 2013, 03:29 PM
TurboEF
Dec 30 2013, 10:29 AM
I'm going to look at the dimensions of the engine bay, but have you ever thought of using a non native motor in here?
There are a number of people who have transplanted Honda motors into Metros/Swifts.

There's even people who have transplanted V6 and V8 drivetrains.
I've seen a couple Honda swaps, but what haven't they put a K20 in?

It was just a thought.
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