A/F and Temp
05-22-2008, 05:37 PM
#1
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A/F and Temp
The weather here in NY varies greatly this time of year. One day it could be 55 the next 85. I have noticed the cooler it is the higher my A/F ratio is. For instance at 50 deg say at 6000 rpms it could be 12.4 and the next day say its 75 deg, my A/F at 6000 is 11.8. I am assuming this is normal. What a pain in the *** CIS is. I am debating on this Digital warm up regulator.
05-23-2008, 12:15 PM
#2
Burning Brakes
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Yep, it's all about air density...colder air being more dense. Unfortunately with CIS, I don't think there's a provision in the fuel delivery system(s) for taking air temp into consideration. Engine temp yes (by the WUR), but air temp...?
05-23-2008, 04:59 PM
#3
Racer
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I re-tune my CIS every summer and winter. Most of the discrepancy can be taken out with a 1/16 turn of the idle mixture screw. Unless you run the ragged edge of tuning it is not that noticeable.
05-23-2008, 06:10 PM
#4
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I have read that the mixture screw really only impacts the A/F ratio at idle. Is that not the case? Does it impact fueling throughout the rev range? Need to get me an AFR set up so I can play with that!
05-23-2008, 09:49 PM
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Racer
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John,
you think too much...just drive the damn car!
My AFRs do the same thing as long as they're in the safe range I don't worry.
By the way, I went to Hooked on Driving's Pocono North DE w/ Rik yesterday. There were suppose to be 5 of us from CIM, but only 3 showed. You should come next time.
Scott
you think too much...just drive the damn car!
My AFRs do the same thing as long as they're in the safe range I don't worry.By the way, I went to Hooked on Driving's Pocono North DE w/ Rik yesterday. There were suppose to be 5 of us from CIM, but only 3 showed. You should come next time.
Scott