T-leg Piggyback ECU R&D

vrg3 · Post by **vrg3** » Sat Feb 19, 2005 4:42 pm

Why would you have to run wires through the firewall?

If I were in your position, Chris, I wouldn't take on the responsibility of providing base maps. Unless you have a lot of dyno tuning experience that I'm not aware of...

Kelly · Post by **Kelly** » Sat Feb 19, 2005 8:23 pm

vrg3 wrote:Why would you have to run wires through the firewall?

If I were in your position, Chris, I wouldn't take on the responsibility of providing base maps. Unless you have a lot of dyno tuning experience that I'm not aware of...

I would love to start with a base map, but Vikash is right, this might be a liability for you man.
Maybe we ought to start a new ECU tuning section on the site. You could merely suggest some maps, and members could suggest some of therir own modifications, and we could have happy little discussions about tuning for years to come

free5ty1e · Post by **free5ty1e** » Sun Feb 20, 2005 1:30 am

That works. I definately don't want that liability lol use this product as any aftermarket product at your own risk

I just meant as I got my car running with certain configurations, it might be nice for me to share those maps with everyone. I like the ECU tuning section idea.

You'd have to run wires through the firewall for any signal that had to terminate anywhere but the ECU - like for the MAF and MAP input signals, for example.... and the spark outputs to the ignitor... and the boost control solenoid output...

vrg3 · Post by **vrg3** » Sun Feb 20, 2005 1:32 am

The MAF and MAP signals can be tapped or intercepted at the ECU.

free5ty1e · Post by **free5ty1e** » Sun Feb 20, 2005 1:36 am

lol... I guess you could do it that way too. They are already run arent they? Man I need to stop posting before I think.

azn2nr · Post by **azn2nr** » Sun Feb 20, 2005 6:45 am

count me in.

im still a little confused though. do you have to have a laptop to tune this thing? and is it similar to a utec?

free5ty1e · Post by **free5ty1e** » Sun Feb 20, 2005 2:25 pm

No laptop will be required to tune (the unit has a display and buttons), but will be an option for additional convenience in tuning, backing up settings, and sharing tables/maps with other users.

No idea what a UTEC is, but this product seems to be a smattering of features from things like the s-afc and the e-manage...

free5ty1e · Post by **free5ty1e** » Mon Feb 21, 2005 3:29 pm

Update - worked out a temporary mount in the car on the passenger side dash for experimentation. Almost have the MAF sensor reading out on the display in selectable units of ADC reading, voltage, and grams/sec. I'll throw CFM in there at some point but reading the MAP sensor is next. I'll just tap into the signal before the FCD clamps it and read from that. Then it's tach pulse timing time and I'll be able to start experimenting with the airflow table and trims...

legacy92ej22t · Post by **legacy92ej22t** » Mon Feb 21, 2005 4:50 pm

Hehehehehe, sweet.

stipro · Post by **stipro** » Mon Feb 21, 2005 7:44 pm

legacy92ej22t wrote:Hehehehehe, sweet.

Second!!!!

azn2nr · Post by **azn2nr** » Mon Feb 21, 2005 8:29 pm

this is gonna be so tight.

utec is a user tunable ecu control. bascily a realy complicated piggy back for wrx's made by txs.

so this going to be able to control fuel and timing???

free5ty1e · Post by **free5ty1e** » Mon Feb 21, 2005 10:45 pm

Yep, timing can be retarded directly (timing advance will be possible in later revisions as it requires additional development), and fuel can be controlled indirectly by scaling the mass airflow sensor's signal appropriately. Tuning will be adjusting tables of trims, either on a laptop or on the unit itself (it will be easier to tune on a laptop of course)...

Edit: It'll also be able to adjust/control boost using the stock boost solenoid. So fuel, timing, and boost control.

evolutionmovement · Post by **evolutionmovement** » Mon Feb 21, 2005 11:06 pm

Would the planned future timing advance feature be just a software download?

Steve

free5ty1e · Post by **free5ty1e** » Mon Feb 21, 2005 11:09 pm

I'm also looking for some quick and failsafe way to connect to the ECU, as that is where everything I need is located. Anyone know where I can get those ECU connectors, males and females? Or maybe just that connector in a pass-through/barrel configuration?

I was thinking if I could find something like that, I could just have that all wired up to the unit already, and to install it you'd just unplug your ECU connectors, plug them into my connector, and plug that into your ECU. No wiring - plug and play!

And, should the controller lose power, that would also make it possible for a relay to automatically switch to a circuit that passes the ignition, airflow, and boost signals straight through so the car will still drive normally. Lots of good ideas...

free5ty1e · Post by **free5ty1e** » Mon Feb 21, 2005 11:12 pm

Well, if you had a PSoC burner you could just download software updates to burn to your chip, yes. But if not, worst case would just be purchasing a new chip to replace the old one.

Another option for upgrades would be shipping me your chip, I could burn the new firmware for you and send it back ASAP, with fedex this could be a one or two day turnaround. Unfortunately your piggyback tuner would be down for that period of time.

vrg3 · Post by **vrg3** » Mon Feb 21, 2005 11:21 pm

To get the mating pair of connectors, you can cannibalize a stock ECU and harness. That's why it costs so much for me to make a plug-and-play FCD.

I think to reliably advance timing you would need a little more hardware... A robust high-input-impedance zero-crossing detector to pick up the crank angle sensor's signal.

The relay that switches signals straight through is a good idea for other reasons too... It's always good to be able to go back to stock by just hitting a button.

You know what I just realized? It's kind of dumb to require a separate tach signal. We have both ignition channel signals already!

THAWA · Post by **THAWA** » Mon Feb 21, 2005 11:35 pm

free5ty1e wrote:I'm also looking for some quick and failsafe way to connect to the ECU, as that is where everything I need is located. Anyone know where I can get those ECU connectors, males and females? Or maybe just that connector in a pass-through/barrel configuration?

I was thinking if I could find something like that, I could just have that all wired up to the unit already, and to install it you'd just unplug your ECU connectors, plug them into my connector, and plug that into your ECU. No wiring - plug and play!

put me down for some of that! I have a couple ecu's sitting here I could donate if you wanted to try and do that. I could also go down to the JY and cut the other end of the harness for ya.

free5ty1e · Post by **free5ty1e** » Mon Feb 21, 2005 11:46 pm

That would be quite helpful, THAWA.... I'll PM you with my address. I'm sure once we've got something ot cannibalize for this connector, we'll find an equivalent source to use for the end product. It may cost a bit more to have this connector made for your tuner, so it'd be an option. But I think it'd be a good option to have! (and of course for your donation you'd get the option for free with yours, as is only fair)

As far as the timing advance, yes exactly - before we make a circuitboard I'd ensure a plan was in place for the timing advance. Detecting transitions or zero-crossings is no problem, I have four comparator busses and lots of blocks that could be used to drive them. It'll be in the overall design, is what I'm trying to say. Thats what this discussion is for

vrg3 · Post by **vrg3** » Mon Feb 21, 2005 11:54 pm

Cool... well, a simple comparator might not do the job. Automotive variable-reluctance pickups are noisy and hard to reliably monitor. You might want to consider the LM1815; it's a whizbang VR amp with adaptive hysteresis.

THAWA · Post by **THAWA** » Tue Feb 22, 2005 12:04 am

How many do you need? I'll have 4 spares in a few weeks but I'd like to hang onto a couple.

Also all these extras are starting to add up, is the price starting to add up aswell?

free5ty1e · Post by **free5ty1e** » Tue Feb 22, 2005 2:25 am

Nothing so far except this plug and play Legacy ECU connector that may take a bit of extra parts and labor to make would incur any additional costs so far. All the other features discussed can reside on a single chip with room to spare.....

If I could have two of those ECU's to mess with that would be all I'd need, is that OK? If not then one will do. And of course two sets of connectors would be great too although if you can only find one set at the JY thats OK I will figure something out. I've found that sometimes experiments like when you've got backup parts

You've got all turbo ECU's, right? Or do the N/A ECU's have the same connectors?

Oh and Vikash - I've added historesis to a comparator before, that's doable too. Noisy signals are not new to me.... I bet I could still keep it all inside the PSoC, timing advance and all. If I ended up needing extra circuitry then no problem, I'd just offer a small module to add on. Hopefully that won't be necessary, though. I like taking care of everything in the one chip.

azn2nr · Post by **azn2nr** » Tue Feb 22, 2005 2:36 am

if you will be able to adjust timing in both directions far enough couldnt you incorporate an antilag swich in there.

also will you be able to save adjustments as maps to siwch in between so you would have your racing and street maps?

plug and play would be really cool. it would help people like me out alot.

free5ty1e · Post by **free5ty1e** » Tue Feb 22, 2005 2:44 am

Jason- yep, theres plenty of room in flash memory to save multiple copies of the maps. You can quickly have access to I'd say 4-5 different sets of maps without too much trouble for different conditions if you'd like.

Please excuse my ignorance, but what's an antilag switch? Once I've got control of the timing, I can indeed adjust it to extremes in both directions, so I'm sure what you're suggesting is possible. But some elaboration on the topic would not be unwelcome.

Yes I really want to work out a plug and play option for the Legacy. It will still be usable on other airflow-based cars with some changes, but we'll have our quick-connect solution for aftermarket engine management.

free5ty1e · Post by **free5ty1e** » Tue Feb 22, 2005 2:59 am

Just thought of something. I'm already going to be reading/timing the tach/RPM pulses. Wouldn't these pulses give me the timebase I need to properly advance spark? Or one I could at least use? The tach pulses are already nice and clean and filtered pulses.....

Maybe some sort of absolute ignition timing trims, measured from the tach pulse instead of where the ECU puts them. That would allow for effective timing control over the whole range of available locations to create a spark through time.

azn2nr · Post by **azn2nr** » Tue Feb 22, 2005 3:09 am

as far as i understand it anti lag is used in rally cars and the timing is either advanced or pulled back so that the fuel would be unburnt until it reached the exhaust maniflod so that it would detonate in the manifold therefore spooling the turbo while at idle. when you hit the gas timing reverts back to normal or race map whichever is selected at the time. with the swich for it though you could turn it on when you want it by holding a button or something and when you let go its not operationable so that when your done racing the antilag wont reengage.

thats how i understand it. anyone can chime in if im wrong somwhere.

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T-leg Piggyback ECU R&D