Hard Question: Plotting Advance Curve

[jono1986]

Thanks cameron that is exactly what i'm looking for, the kit comes with a coil driver (not pictured). The instructions show how to dis-engage the mechanical advance and also how to hook up a MAP sensor to the system, oh to by a new MAP sensor it's about 150bucks or over, but i'll probably just borrow one from u pull it. And Philbey what do you mean "setting to a particular timing point as well?"

[philbey]

Jono, are you thinking of a factory automotive MAP sensor? I'm pretty sure the Jaycar kit has a spot on the board for a basic PCB mount pressure sensor? If those things are worth 150 bucks, I'm pissed off, I had a bunch of them in an old box at work that they didn't need! Not any more though!

 

What I mean about setting a point (sorry about the poor wording) is that I'm pretty sure you set the dizzy to 0 degrees BTDC and the timing map does the rest? Or do you set it well in advance? I can't remember..... Read the Silicon Chip article ages ago.

 

EDIT: I just found this quote from Silicon Chip:

 

In order to measure engine load, the Programmable Ignition can use a Sensym absolute pressure sensor. In fact, provision has been made to mount this sensor directly on the PC board, the sensor then being connected to the engine manifold via plastic tubing.

 

Alternatively, you can connect the ignition circuit to an existing manifold pressure sensor if present. This is commonly called a Manifold Absolute Pressure (or MAP) sensor and is found on many cars these days. You could also use a secondhand MAP sensor from an auto wrecker.

Edited October 20, 2009 by philbey

[Taz_Rx]

What I mean about setting a point (sorry about the poor wording) is that I'm pretty sure you set the dizzy to 0 degrees BTDC and the timing map does the rest? Or do you set it well in advance? I can't remember..... Read the Silicon Chip article ages ago.

 

Well in advance. :) My wolf's reference is set at 60*BTDC - and the ECU knows this. It can then advance the timing up to 60*.

[jono1986]

Nuh it says to set the distributor at 0 deg's, then the system will go from there. otherwise idle would be 0 deg's or whatever the ditributor is set at.....so if its at 20 deg's that means that idle would be -12deg's. And yeah you can mount an Sensym MAP sensor to the board but Jaycar don't supply them (the irony). reading the instructions in depth at the moment so will comment a bit more later

[philbey]

Bloody hell - I just looked them up on Farnell

 

farnell Sensym Pressure sensors

 

100-200 bucks, ouch. I can't believe how many of these there used to be lying around work!

 

I'm certain you'd be able to get a similar, cheaper sensor to work.

[Felix]

Can't just us a MAP sensor out of some car? Guess it comes down to if the voltage range is compatible with your ignition kit.

[Taz_Rx]

Can't just us a MAP sensor out of some car? Guess it comes down to if the voltage range is compatible with your ignition kit.

 

+1 pending voltage - Though you may be able to set this somehow in the Jaycar kit. Or does it list a voltage range to use?

 

This is brand new and cheap....

 

http://cgi.ebay.com.au/KIA-RIO-MAP-SENSOR_...=item45eeb498ae

 

:lolcry:

[jono1986]

The map sensor has to have an output voltage between 0-5v and since the max pressure of my engine will be about .35 bar it will be easier to use a 1 bar sensor, commonly used in VN-VS commodore. Visiting U-pull-it tomorrow to see what i can get. Oh and taz-rx it has to come with a plug, but other than that its very cheap for a Map sensor

[philbey]

I've come across plenty of other differential pressure sensors that run 0-5v, my mate had one lying around that we dabbled with for a while.

 

I'll see what else I can find on Farnell.

[jono1986]

Thought i'd put an update in, going to do a seperate thread for it but just reading some stuff and have some answers. got a MAP sensor from a vr i think from u-pull-it for 8 bucks :wink: bit better than a few hundred, also another member is sending me a locked dizzy so should be setting it up next weekend hopefully, along with a weber maybe. Also have done a graph in autocad, but the previous pictures supplied and the manual don't line up so i'm just going to set it up for 8 deg at idle and slowly ramp it up to 25 deg at 3000 rpm, then refine in as i drive along. The Vacuum is easy, just have to map out 15 points of vacuum from 3.94 in. Hg to 8.66 in. Hg except in bar :hmm: .