I want to try and learn a bit, build my own boost display

[paulr33]

Hi All,

I wanna learn a little in regards to electronics and general car crap as I dont know that much and found a howto in regards to building a display meter based off the boost or vacuum pressure. The howto is a for 200sx however @ http://www.200sx.org/boost_gauge_1.html

Does anyone know if this similar plan would work for an r33?

I'm just looking for something to fiddle around with and learn some stuff on, nothing pro style etc...

Thanks

[hippy]

actually it would be pretty simple .. u would need the following depending on how sophisticated u wanna be and how much time u wanna waste ... u need an electrical boost detector, pressure sensor .. i'm not sure how they work but i would assume they convert pressure sensed into a voltage, then its simple ... just do some tests to calibrate a particular voltage to pressure and then use a micro controller which u could also use as a boost controller ... buy an LCD screen ... one of them character types, people who know what i'm talkin about would be one of them hitachi types and they are hell easy to use, they are found on things like micro tech displays and i think even the powerfc hand controller .. but yeah they are easy to program ... do some tests ... the program would be pretty simple ... but yeah if u have lots of time to waste it wouldn't be that hard .. especially if you're an electrical/computer engineer like me

[paulr33]

OK well what would the starting point be? I dont even know what parts I need

[paulr33]

Ok What would be involved If I wanted to read in the vacuum pressure? I would need a map sensor (any idea how much $$?) and I would then hook this up to the boost sensor or thereabouts which would then return a voltage?

Is there a kit tha can already do this? My end goal would be engine diagnostics in real time to a laptop. Things like rpm, vacuum pressure, idle sensors and that sorta thing.

Would there be a kit to suit my needs or do I have to go the manual hack? I know a few electronic gurus etc so that will help as well...

Any input would be great.

I do recall a serial port data logged of some description but dont have any details. Does anyone have any info on this?

[paulr33]

The thing I was referring to in the above post was the Trust Emanage (I think) and will actually allow you to change most of the stuff. I dont want to change any of, just monitor and/or data log for future reference. So read only of all the data is fine

[hippy]

ur best bet i think would be getting the signals coming into the computer .. i'm not sure what the protocols of the signals are .. u gotta research it and if its not available then u have to do manual testing urself which would be a bitch ... alot of work ... i'd just go buy a powerfc or a microtech

[paulr33]

do you have any specs/url on the microtech stuff?

The powerfc is not really what im after, i dont wanna change stuff, mainly just monitor and learn from driving patterns etc..

PowerFC would be fun though

What do u have one u have the powerfc installed? u must have the hand controller too or it just hooks to a laptop?

[hippy]

i dont' know .. i'm not sure how powerfcs work ... they are just a replacement computer ... i dont' know how apex gets all their data from since they have a powerfc for most jap spec cars ... its a huge job to want to do what u want to do ... thats why they sell gauges LOL

[DAMQIK GTS-T]

paulr33

Two things

1: Your car should already have a map sensor its is used to drive your factory boost gauge its located next to the brake booster, it has three wires going two it Gnd, V+ and Signal.

2: There is a serial data point under the dash drivers side (works with only std ecu) in the fuse box (you will need to make a plug to fit it) I will try to find its pin out and post back here.

Regards Damqik

[DAMQIK GTS-T]

Here it is,

Note: you will have to find some software to get dataloging from this port:

[paulr33]

Hi Damqik,

Is this the plug u are referring to, its just inside the Fuse box area, well sort of anwyay. See attachment

[paulr33]

Is there any associated nasties with attempting to use this port for data logging? Anyone have any ideas on what sort of data I can access? I've found that sort the two bottom row'd wires is another way of doing ECU reset, but im after sensor readings more specifcally.

Any help would be great

[DAMQIK GTS-T]

Yeap thats the port,

it is what Nissan Japan plug into and get readings of all sorts from the ecu.

[b2barker]

Displaying boost with a series of LEDs seems like a waist of time to me. As you need to get a MAP, why not hook it straight of the LCD loop powered digital display?

I don't think the stock gauge uses a MAP, I thinks in air powered? Isn't it?

If you want to embark on some automotive/electronic stuff I recomend Autospeed , it's well worth the money. Search there on displays.

For what it's worth maybe you would be better off making a datalogger. If you have a laptop, you could hook this data acquisition unit up. Eight 0-4V 12-bit inputs logged to laptop. Log speed, rpm, boost, temps, TPS ...

The ECU port won't give you boost, as there is no boost signal into the ECU.

[paulr33]

Hi b2barkey,

Does the "data acquisition" plug into the diag port and then i can plug in a serial cable and use their software? This sounds awesome!!!

I've read the review you posted and it sounds good, but I just want to be sure it will plug into the diag port or does it need something to do that?

[DAMQIK GTS-T]

Originally posted by b2barker

I don't think the stock gauge uses a MAP, I thinks in air powered? Isn't it?

No, Its driven by a MAP sensor Look next to the Brake Booster on a R33.

I agree Autospeed is an exellent source of infomation for car eletronics,

Also Try:

http://www.aaroncake.net/circuits/index.asp#power

http://www.teamfc3s.org/info/articles/fcd/diy_fcd.htm

http://www.uoguelph.ca/~antoon/circ/circuits.htm

I have made some of these including the FDC and all have worked

Regards

DAMQIK

[DAMQIK GTS-T]

Originally posted by paulr33

Hi b2barkey,

Does the "data acquisition" plug into the diag port and then i can plug in a serial cable and use their software? This sounds awesome!!!

It would be good if it did,

But I doubt the data acquisition would work this way as the diag port sends serial infomation (binary?) the data acquisition senses voltage output.

Maybe the "Nissan ecu rom editor" (do a search) would be better to make some sence of the data coming from your ecu.

I never got this far as I ended up going aftermarket ecu.

You could also try downloading the link ecu program as it reads serial data from its ecu.

Regards

Damqik.

[paulr33]

Originally posted by DAMQIK GTS-T

No, Its driven by a MAP sensor Look next to the Brake Booster on a R33.

DAMQIK

OK so I was to purchase one of these kits @ http://www.oceancontrols.com.au/data_acqui...sition/isee.htm

This can then directly plug into the MAP sensor port next to the Brake booster? Do you have a pic of what the connetor looks like (the brake booster) so I have an idea where to find it.

Once I'm connected to this "MAP" sensor I can then in theory using their software obtain the data you mentioned above.

This has never been tried before has it? :^)

Let me know if Im on the right track

Thanks heaps for your valuable input

[DAMQIK GTS-T]

Its Part E In the Picture,

Under the Bonnet between the shock tower and firewall.

Its hanging off the same bracket that holds the throttle cable.

Thats The best discription I can give.

I can't take a photo as I no longer have one in my car I have changed my dash and removed and sold it.

BTW it dose not need to be hooked to the factory wiring as it only runs the factory boost gauge and thats it.

[DAMQIK GTS-T]

Originally posted by paulr33

OK so I was to purchase one of these kits @ http://www.oceancontrols.com.au/data_acqui...sition/isee.htm  

This can then directly plug into the MAP sensor port next to the Brake booster?

Yes

Originally posted by paulr33

This has never been tried before has it? :^)

Nothing is new under the sun, however I havn't seen it done, but then again for what purpose would one want to data log their boost presures only?

Wouldnt it be more important to log a a range of data such as

A/F ratio's

engine speed

Boost at a given RPM

Pinging

ect ect

I belive that the serial port that I first showed you will give all this and more.