My life, My coding

[Rx7man]

OK, I've finally gotten the courage to commit to a data transfer method and start writing a VB program that will read the serial port for the current status of the program and display it in a manner you can view while driving without having to squint and take your eyes off the road for too long.. this will help me figure out what's going on at critical times, and will help greatly with tuning...

I'm kinda fighting the low-RPM, high TPS response, I think it's closing too much in some instances and because of that, it's not spooling well and it's putting a huge load on the engine in the form of backpressure... which just makes it react sluggishly.

I'm trying to make an Uno compatible version, but since I have a lot of text strings I'm having memory issues.. I will have to see what I can do about putting it in program memory or something.. it'll increase complexity and decrease readability.. but we'll have to see where it goes.

Merry christmas y'all

[Rx7man]

Well, over christmas I had lots of time, and as much as my energy would allow me, I slaved away at making something I could look at while driving, displaying things in nice fat bold fonts with a 'gauge' style visualizer.. I haven't quite gotten that mastered yet, but it does display trackbars and labels.

I had to FIGHT LIKE HELL to get VB to read the serial port in a timely manner.. it turns out "Serial.Readline" is a blocking function, which hangs the Arduino connected to it as well.. I had to use "Serial.ReadAvailable", make my own buffer, then parse the data after I didn't get any new data for about 5ms, that fixed everything.  I have it set to update every 1/4 second, which is pretty quick, and it's easy to slow down if I feel like it

Here's a sneak peak at a very preliminary version

[Rx7man]

Oh.. and here's a cold start on my truck, about 10F  -15C

https://www.youtube.com/watch?v=DdKjM3onXOw

LOVE the sound when it starts spooling

[Rx7man]

OK, I got the turbine speed sensor back up and running... Just in time for my exhaust pressure sensor to pack it in... I double checked it and there's no 2 ways about it.. keeps reading about 20 PSI no matter the pressure I apply to it, and I swapped it to the intake side connector to make sure it wasn't a wiring problem... nope.

At this point I'm not relying on it much anyhow... it's one of those things that would be 'nice to have' but I can run pretty well without... it's more of a diagnostic/tuning tool than a necessity to run.

I've taken a few people for a ride in my truck, they're pretty impressed with it... If I have a load on, I can quite easily get 15 PSI by 1300 RPM, or 20psi by 1500... I will say that's darned close to the surge line though, and certainly not in it's efficiency area... nevertheless, it's pretty cool.
As for power.. it's doing pretty good there too.. we got some snow here, and driving to town in 4x4.. studded tires all around, it'll go squirrely in 5th at 70mph.. your butthole puckers up pretty good when it does that.

[hakcenter]

So that VR ended up kaputting ?

[Rx7man]

I guess it did. I didn't change anything else... *shrug*  who knows what the gremlins were doing

[65fpvmustang]

your display looks really nice. right there with steeds $700 controller.

[Rx7man]

Thanks, it gives me motivation to keep going!  I do want to make some improvements to it yet for readability in light/dark, but the basics are coming along... it's at least functional and enables me to do the tuning.

I'm also still working on the theory to redo some of my logic, changing the 'compensations' from absolute position to a percentage, since a 100 point change when you're near closed is drastic while when you're near open it's only mild.. I think once I implement that I will be able to get a quicker spoolup.  Exhaust pressure gauge would help with that as well, but no such luck... I found a fuel pressure gauge from my Rx7 I may be able to adapt... worth a shot I guess.

[65fpvmustang]

retired oil pressure gauge is what i put on my dash.
but these senders are dirt cheap. I got one to put on falcon to monitor oil pressure.
ms3 has check engine light for oil pressure curve high or low settings.

http://www.ebay.com/itm/271763798948?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

[Rx7man]

That looks pretty good!.. I see a 100PSI version which I'd probably get because it's plug-and-play with what I already have

Pressure Transducer or Sender 100 PSI Stainless Steel for Oil Fuel Air Water | eBay

I'd probably just get a bunch of them for doing other things with in other scales. they're handy to have.. thanks for the link

[65fpvmustang]

Yeah i was looking at the 60 psi versions for my lpg pressure and EBP.

[Rx7man]

For the exhaust I'd go with 100 PSI, for manifold pressure I'd go with 50 PSI for my purposes, given the choice.. I just wen with 100PSI all around.  I put a 1000 PSI for my brake pressure and that works pretty slick too.



In other news I finally got to test out my turbine shaft speed sensor and coding.. I had a small glitch I found and corrected quickly... I had used an unsigned integer where I should have used a long, and as such my indicated speed only got to about 64,000 RPM.. fixed that and tromped on it hard in 5th, pretty much redlining the engine at 30 PSI, my peak shaft speed was 114,000 RPM, so I have nothing to worry about there... Temps are pretty cool right now though, and as things warm up I'm sure that will change.  my peak acceleration I think is about 50,000 RPM/second.

I have more bugs to work out on the logging side of it before it works right.. I'll get to it and post up some logs soon.. perhaps I even get it done between dart games tonight

[Rx7man]

OK, I'm working on V1.3 now... big change is the compensators will  affect the percentage of nozzle size opening rather than an absolute position, this should help prevent the bog from closing too far at low RPM.  Took a major rewrite and I change the program flow a little bit too... I'm going to try it so that all compensators are summed together and then applied

[Rx7man]

Well, a few updates I guess I should mention...
I did implement the changes I spoke of, it is definitely better using a percentage compensation than an absolute position compensation, and it's completely logical too.. it's just harder to implement and it took a little fiddling to get right..  With a heavy load I got 18 PSI @ 1400 RPM, and capable of 35 @ 2000, though I usually start limiting it before then..
Truck pulls darned good anyhow.

Meanwhile, I finally got around to chasing down exhaust leaks, pulled the turbo off, EGR delete caps, etc.. didn't go as far as the manifold, but I can fiddle with that one later if I still have problems..
So as it turns out I didn't get the center section clocked onto the pin right, and smushed the pin, which left a tiny little hump, and that was the reason for a very small leak from that area.. ground the pin flush, cleaned it all, never seized it and put it back together.. Rear EGR delete cap was definitely a bad leak, gooped the gasket with muffler cement and put it back on.. did the front while I was at it but I don't think it was bad.
Will test it out tomorrow on the drive to town, I'm guessing my exhaust brake will be far more effective and it'll build boost even better...

It's super warm here today, about 45F (9C), was windy, then suddenly the wind quit and it started pizzing rain... Driving to town tomorrow will be like driving on a bar of soap, ice about 1 or 2" under some real goopy mud... I'm sure I'll find a way to have fun in that.

Other news (just so I can find it again) is here.. Merritt's governor spring install and Tommy's upcoming timing cover gasket fix.. (not really looking forward to it, even though the money is good) Satisfied customer

[Rx7man]

Well,.. I'm looking at the 3.2" TFT touchscreen I got, and the Mega that it's mounted to, and I'm really wondering about how I should connect it to the Mega on the other end.. is I2C usable for intercommunication?

Then there's the question of the transfer protocol... I'm really wondering how I'm going to go about that so it's flexible enough, error recovering, etc and doesn't take massive effort to parse.

You guys have any ideas?