Cis lm2 afr
 

Hi guys I've done some searching and reading but can't seem to find the info I'm looking for.

I have a 76 2.7 with cis

I've recently gotten this car back on the road after many years of sitting. My pressures are with in spec and according to the spark plugs my mixture looks good. I have a lm2 and would like know what numbers should I be seeing at idle, highway cruising and and wide open.

Would some of you mind posting numbers and graphs if you have them.

Thanks Tim

PS the car is registered in AZ so I don't have any concerns about passing smog or inspection.

I played around with the mixture on my 77s a LOT before I got an LM2. in the end what I was doing before I had the LM worked after I had the LM.

I would set the mixture richer and richer until one of things happened (at idle).
either it would surge after idling for bit or when I let off the gas the RPM would drop below idle then come back up. once I reached one of these to symptoms I was too rich and then I would back it off until it did not do either one. I don't remember the exact AFR at idle.

another thing you can do is set your steady cruise AFR to 14.5 up to 15 and see where you like it.

this is a good way to get in touch with your car and learn it.

another approach is if it runs fine where it is don't mess with it.
hot plugs can also make a rich mixture look ok.

T77 that's pretty much the procedure I went through to get the car to the point I am now. http://forums.pelicanparts.com/uploa...1539710217.jpg

I can't remember what plug I'm running at the moment but it's the ngk equivalent of the Bosch wr7dc

I have a well running 3.0 w/ CIS. Runs mid 13s at idle, 14.0 highway cruise, and 12.5 WOT.

looks like that plug is an NGK bp8es. that's very cold. that's a turbo plug heat range or very hi comp engine heat range.

T77 what do you prefer to run?

My plugs are burning very clean but I do have a little bit of a lumpy idle

I am running CIS w/LM2 on a 3.3SS engine in my 1980 SC. Having the AFR is really a blessing, making it much easier to get good settings. Once warmed up a bit, my engine idles at about 14.5, cruises between about 14 and 15 and goes to about 13 at WOT. Good strong idle with good throttle response. I did have to play with the timing and the air idle adjustment some to get everything happy. I am using XDi twin plug, crankfire ignition that is very adjustable using 4 setting knobs on the control box.