How would I go about monitoring my engine outputs?

[Guest lan_killa]

captain K...

ive been having a fiddle with data logging etc in the wrx... Ill bring along the laptop (full charged) to the next meet if you want to have a gandar at it?

[Swindog]

You dont actually really need a wideband btw. You can work off the voltage of the o2 sensor. Its not foolproof but you can get pretty close.

I have a link and been looking at hooking it up to a in car dvd as gauge display but then i see they have a displaylink which will do everything and i can customise the gauges i want.

[cpt kernow]

Looks good, sofar.

I'm not a power hungry dyno fiend, but when a car is sold, Subaru don't know who's gonna buy it so all the settings are compromised. I wanted to drive around and map what my car's doing then think about it and maybe tweak some stuff. Like changing the boost map or injector cycles. Eg If I swapped to yellow injectors and flattened off my boost curve I could I'd be able to adjust the fuel needed without swapping out my ecu or afm.

I do stuff like this, not because it's the easiest or chepest but the most rewarding.

Like at the moment I'm building a valve amp for my home stereo because I can, not because I need to. I could buy one better, maybe (not likely) cheaper but that's not challenging

[Swindog]

 cpt kernow said:

Looks good, sofar.

I'm not a power hungry dyno fiend, but when a car is sold, Subaru don't know who's gonna buy it so all the settings are compromised. I wanted to drive around and map what my car's doing then think about it and maybe tweak some stuff. Like changing the boost map or injector cycles. Eg If I swapped to yellow injectors and flattened off my boost curve I could I'd be able to adjust the fuel needed without swapping out my ecu or afm.

I do stuff like this, not because it's the easiest or chepest but the most rewarding.

Like at the moment I'm building a valve amp for my home stereo because I can, not because I need to. I could buy one better, maybe (not likely) cheaper but that's not challenging

I should send you some of the logs of my car i have in the last few days to get an idea. They are pretty solid and fueling is perfect and in the right zones. Apart from looking like i will max out the injectors if i up the boost from 15psi now everything is sweet. Youd need PCLink to read them though.

[cpt kernow]

That could be good. See if it's got what I want before I start buying parts.

I'm waiting for my pclink torrent to finish then I'll be all good.

cheers

[Swindog]

PM after tea tonight mate ill flick you a couple through.

You see some slight discrepancys with my boost curve but its because i havent set the wastegate gain up properly.

Everything else is spot on.

I judge the air/fuel via the o2 voltage reading and i have a chart to compare too.

[suubyduuby]

Reckon it should be possible to build an OBD to PC interface for less than $50. Most expensive bit is the OBDII plug which you can get at Jaycar electronics for $30....am going to have a crack at this in the next month or so, as I want to monitor and do some logging on on my leggy and a friends Silvia...Who knows, maybe the possibiltiy exists for cheapie solution which could be good for diy tuners?

[Swindog]

Go for it. If you can make a link serial for me even better! or a usb com unit to plug into it for less than $80.

[Durty-Sanchez]

I did my PC -> OBD tool for ~$30, and the most expensive part by far is the plug.. definitely do-able

[nzkaosnz]

is it just a 12V Logic to 232 circuit?

[Durty-Sanchez]

Serial cable (already had one) -> serial/232 converter chip ($5) -> bastardised sziklai pair for amplification (2x transistors ~ 20c) -> socket ($19.95) -> Car loom.

There's a few added extras in there too though, like 5v voltage regulator ($3) that draws power from the OBD port (12v). There's also pull up resistors, protection diodes, capacitors, crap like that, that probably only cost like $1 total.

I wrote the scan software myself though, although im sure most downloadable stuff works just fine.

[Swindog]

Reckon you could build me a cable for the link?

[nt_a_foz]

 Swindog said:

You dont actually really need a wideband btw. You can work off the voltage of the o2 sensor. Its not foolproof but you can get pretty close.

I have a link and been looking at hooking it up to a in car dvd as gauge display but then i see they have a displaylink which will do everything and i can customise the gauges i want.

yeah man i was looking at these as opposed to a gauge..you can get a displaylink for liek 900 bucks little lcd screen that can do anything you want pretty much with monitoring the cars vitals...you can choose what gauges you want displayed etc...

[Koom]

 nt_a_foz']

[quote name='Swindog said:

You dont actually really need a wideband btw. You can work off the voltage of the o2 sensor. Its not foolproof but you can get pretty close.

I have a link and been looking at hooking it up to a in car dvd as gauge display but then i see they have a displaylink which will do everything and i can customise the gauges i want.

/quote]

yeah man i was looking at these as opposed to a gauge..you can get a displaylink for liek 900 bucks little lcd screen that can do anything you want pretty much with monitoring the cars vitals...you can choose what gauges you want displayed etc...

Buy one of those mini laptops, plug into the Link, put the guage dsiplay from PCLink on fullscreen and set the laptop to hibernate whenever you turn the car off.

Can also drive round and scope out free wireless hotspots and D/L some videos of donkeys etc

The little laptops can probably be bought for about $900 or less aswell.

[nt_a_foz]

haha yeah well or you could do that lol..

dave has one of those for the tuning....

[suubyduuby]

 Durty-Sanchez said:

Serial cable (already had one) -> serial/232 converter chip ($5) -> bastardised sziklai pair for amplification (2x transistors ~ 20c) -> socket ($19.95) -> Car loom.

There's a few added extras in there too though, like 5v voltage regulator ($3) that draws power from the OBD port (12v). There's also pull up resistors, protection diodes, capacitors, crap like that, that probably only cost like $1 total.

I wrote the scan software myself though, although im sure most downloadable stuff works just fine.

I take it you must be into electronic/electrical stuff Sanchez?

Same here ;D

OBD to RS232 line driver? Man, that is pretty simple. Thought it would have involved some protocol translation on a micro....if its that simple, then I reckon just whack on a FTDI RS232-USB chip and you've got an OBDII to USB interface...

[suubyduuby]

 Swindog said:

Go for it. If you can make a link serial for me even better! or a usb com unit to plug into it for less than $80.

Well if's a simple as DS has pointed out, not much more to make it USB compatible. Either buy a serial to USB converter, or could whack on a USB converter chip for 15-20 which will take it straight to a USB plug.

Mmmm - real keen to build this now.

[Swindog]

 Koom']

[quote name='Swindog said:

You dont actually really need a wideband btw. You can work off the voltage of the o2 sensor. Its not foolproof but you can get pretty close.

I have a link and been looking at hooking it up to a in car dvd as gauge display but then i see they have a displaylink which will do everything and i can customise the gauges i want.

/quote]

yeah man i was looking at these as opposed to a gauge..you can get a displaylink for liek 900 bucks little lcd screen that can do anything you want pretty much with monitoring the cars vitals...you can choose what gauges you want displayed etc...

Buy one of those mini laptops, plug into the Link, put the guage dsiplay from PCLink on fullscreen and set the laptop to hibernate whenever you turn the car off.

Can also drive round and scope out free wireless hotspots and D/L some videos of donkeys etc

The little laptops can probably be bought for about $900 or less aswell.

If your gonna spend that you mayaswell buy the display link cos its made for it and have a laptop to tune. Which i do. I was thinking headunit as its discrete and can be stored away or retracts when power shuts down.

[Koom]

 Swindog said:

If your gonna spend that you mayaswell buy the display link cos its made for it and have a laptop to tune. Which i do. I was thinking headunit as its discrete and can be stored away or retracts when power shuts down.

But can you steal free internet from outside Starbucks with the displayLink?? haha.

Personally, I just use my laptop to show the data I want off the Link every once in a while and not bother with having something permanent.

Another option is to get an Innovate LM-2 and use that as a datalogger. If you have a newer car it can read and store stuff from the OBDII port aswell. Stores about 700 hours of data on one card.

[Swindog]

Yeah but the point being when im on the track i want to monitor stuff like exhaust temp and fuel ratios. . logging i can do with the lappy sitting on the passenger seat and tuning well you need two people anyway

[Koom]

 Swindog said:

Yeah but the point being when im on the track i want to monitor stuff like exhaust temp and fuel ratios. . logging i can do with the lappy sitting on the passenger seat and tuning well you need two people anyway

Big giant oil warning light and maybe a rev counter for when you're on the track

Nothing else matters.

[Swindog]

I can put oil pressure on the link. And i think i can do a shift meter too.

[log1call]

The easiest way to read subaru ecus at the moment is to us a ftdi usb-tty cable which costs about thirty-five dollars. You just cut the plug off and use three of it's wires straight to the obd port. Use a free software program and you can have gauges on your laptop if that's what turns you on, or, and this is really usefull... you can log the running conditions of your engine so you can look for faults or calculate power gains.

[cpt kernow]

Bingo.

you know what 3 pins to wires?

[nzkaosnz]

 log1call said:

The easiest way to read subaru ecus at the moment is to us a ftdi usb-tty cable which costs about thirty-five dollars. You just cut the plug off and use three of it's wires straight to the obd port. Use a free software program and you can have gauges on your laptop if that's what turns you on, or, and this is really usefull... you can log the running conditions of your engine so you can look for faults or calculate power gains.

And one of those would be obtainable from where?