adjusting fuel mix
Discussion
350matt said:
Peeps
which way do you have to turn the mixture adjustment screw on the air flo meter to lean things off?
3Am meter on a 4.3 griff
Ta
Matt
which way do you have to turn the mixture adjustment screw on the air flo meter to lean things off?
3Am meter on a 4.3 griff
Ta
Matt
The best way is to stick a volt meter across the correct terminals and read the voltage. I haven't got the book infront of me but you don't want the airflow signal... the higher the voltage the richer the mixture is the way its seemed to work for me.
Just bear in mind that the 3 volts which everyone quotes and standard hasn't matched anyones actual reads I spoken to. mine was set to 0.03v.. I got a spare meter to do some testing and its now set to about 1.75v. This is not scientific and may not be the same for yours!! it just seemed run better there.
The allen screw does not need much movement to change the output so be gentle to begin with.
Id be interested what readings you get. secondly the static voltage (I think its call trim does not effect the air flow output voltage at different engine speeds)
Griffsmith said:
350matt said:
Peeps
which way do you have to turn the mixture adjustment screw on the air flo meter to lean things off?
3Am meter on a 4.3 griff
Ta
Matt
which way do you have to turn the mixture adjustment screw on the air flo meter to lean things off?
3Am meter on a 4.3 griff
Ta
Matt
The best way is to stick a volt meter across the correct terminals and read the voltage. I haven't got the book infront of me but you don't want the airflow signal... the higher the voltage the richer the mixture is the way its seemed to work for me.
Just bear in mind that the 3 volts which everyone quotes and standard hasn't matched anyones actual reads I spoken to. mine was set to 0.03v.. I got a spare meter to do some testing and its now set to about 1.75v. This is not scientific and may not be the same for yours!! it just seemed run better there.
The allen screw does not need much movement to change the output so be gentle to begin with.
Id be interested what readings you get. secondly the static voltage (I think its call trim does not effect the air flow output voltage at different engine speeds)
According to the RPI numbers that Joo looked up for me 1.7v is perfect for a car with cats and .7v for decatted.
Whereabouts is this voltage measured?
As Mr Heath's book mentions between Pin 35 and ground, presumably this can be measured at the meter by pulling the boot off and coming off the one of the wires there?
If so which one?
As I had a bit of fiddle today and none of the wire measurements change with twiddling of the screw, the twiddling definitely has an effect tho'
Matt
As Mr Heath's book mentions between Pin 35 and ground, presumably this can be measured at the meter by pulling the boot off and coming off the one of the wires there?
If so which one?
As I had a bit of fiddle today and none of the wire measurements change with twiddling of the screw, the twiddling definitely has an effect tho'
Matt
350matt said:
Whereabouts is this voltage measured?
As Mr Heath's book mentions between Pin 35 and ground, presumably this can be measured at the meter by pulling the boot off and coming off the one of the wires there?
If so which one?
As I had a bit of fiddle today and none of the wire measurements change with twiddling of the screw, the twiddling definitely has an effect tho'
Matt
As Mr Heath's book mentions between Pin 35 and ground, presumably this can be measured at the meter by pulling the boot off and coming off the one of the wires there?
If so which one?
As I had a bit of fiddle today and none of the wire measurements change with twiddling of the screw, the twiddling definitely has an effect tho'
Matt
You have to measure the voltage at the connector, I think it was red and blue wire But not 100% on that prehaps someone can confirm or i will look at my notes tomorrow. I stuck a straightened paperclip down the connector on each wire and then crocodile clipped the voltmeter.
BB
Certainly is measurable at the AFM connector (will dig through my notes for the wire colours if you don't get the info on here during the day), and BB paperclip dodge is the one. Having said that, I ended up getting it somewhere near by measurement and then trimmed from there for best feel/response. I was surprised just how much effect this setting has and it's well worth spending some time to carefully set it up. Added 'bonus' is that for cars that pop and bang, this does influence how much 
Griffsmith said:
Just bear in mind that the 3 volts which everyone quotes and standard hasn't matched anyones actual reads I spoken to.
Sorry I haven't kept up with the thread this weekend. contrary to my post no one quotes 3.0v
I have just rechecked the RPI website www.rpiv8.com/carbs-2.htm#setting-up
This give colour codes of the wires. I know I was about half 'recommended' so it must be 0.75v, will check tonight.. but either way its not as it 'should be' and runs well.. I agree with Griffter set it with a CO meter to be sure.
Gazman just remember this is one of the good ones being a Pre-Cat not a lazy 5.0 or a Kev'd up De-Cat
The cat variant with the 5AM meter has a different 'standard' setting to the Pre-cat 3AM. However I've found the airflow signal at varying revs to be as pretty much as described in the SH book..Gassing Station | Griffith | Top of Page | What's New | My Stuff