tuning d-jet 2.0('75) - A/F ratio, effects on engine temp, Am i running lean on highway?- 14.0 @ 65-70 mph |
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tuning d-jet 2.0('75) - A/F ratio, effects on engine temp, Am i running lean on highway?- 14.0 @ 65-70 mph |
DRPHIL914 |
Jul 16 2014, 06:51 AM
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#1
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Dr. Phil Group: Members Posts: 5,768 Joined: 9-December 09 From: Bluffton, SC Member No.: 11,106 Region Association: South East States |
So i've been able to observe my A/F ratio for the past 2 weeks, driving the car daily to work and some short trips of 30-75 miles.
yesterday evening, with the outside temp being @ 90, i noticed that as i increased my speed from @ 60mph i was running about 190 temp, A/F was @ 12.5-13.2 or so. but as i increased my speed to closer to 70, temp rose to 210 or so, maybe a bit more, and the A/F went up to @14.2 . As i slowed down, and even at idle ,the temp came down to @ 180-190 again. - so is it because of running more lean? could it be timing/advance effecting this ? or do i need to adjust the MPS? cold idle it runs at 10.5-11, warms up and driving around town im around 12.5, hard acceleration in leans out some around 13.5, etc . - its at Bob Woodmans today, getting valves set/checked and timing(lost my timing mark on the impeller) so that will all be sorted out. today and taken out of the equation. oh, and the thermostat works, fins are in the right position , no blockage etc. - running brad penn oil. - |
worn |
Jul 16 2014, 10:17 AM
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#2
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can't remember Group: Members Posts: 3,162 Joined: 3-June 11 From: Madison, WI Member No.: 13,152 Region Association: Upper MidWest |
So i've been able to observe my A/F ratio for the past 2 weeks, driving the car daily to work and some short trips of 30-75 miles. yesterday evening, with the outside temp being @ 90, i noticed that as i increased my speed from @ 60mph i was running about 190 temp, A/F was @ 12.5-13.2 or so. but as i increased my speed to closer to 70, temp rose to 210 or so, maybe a bit more, and the A/F went up to @14.2 . As i slowed down, and even at idle ,the temp came down to @ 180-190 again. - so is it because of running more lean? could it be timing/advance effecting this ? or do i need to adjust the MPS? cold idle it runs at 10.5-11, warms up and driving around town im around 12.5, hard acceleration in leans out some around 13.5, etc . - its at Bob Woodmans today, getting valves set/checked and timing(lost my timing mark on the impeller) so that will all be sorted out. today and taken out of the equation. oh, and the thermostat works, fins are in the right position , no blockage etc. - running brad penn oil. - Are you running an unmolested stock MPS? It seems similar to what I have seen, and how I find the engine wants to run. It should be richer than 14 when you are heading up a hill though. |
DRPHIL914 |
Jul 16 2014, 11:02 AM
Post
#3
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Dr. Phil Group: Members Posts: 5,768 Joined: 9-December 09 From: Bluffton, SC Member No.: 11,106 Region Association: South East States |
So i've been able to observe my A/F ratio for the past 2 weeks, driving the car daily to work and some short trips of 30-75 miles. yesterday evening, with the outside temp being @ 90, i noticed that as i increased my speed from @ 60mph i was running about 190 temp, A/F was @ 12.5-13.2 or so. but as i increased my speed to closer to 70, temp rose to 210 or so, maybe a bit more, and the A/F went up to @14.2 . As i slowed down, and even at idle ,the temp came down to @ 180-190 again. - so is it because of running more lean? could it be timing/advance effecting this ? or do i need to adjust the MPS? cold idle it runs at 10.5-11, warms up and driving around town im around 12.5, hard acceleration in leans out some around 13.5, etc . - its at Bob Woodmans today, getting valves set/checked and timing(lost my timing mark on the impeller) so that will all be sorted out. today and taken out of the equation. oh, and the thermostat works, fins are in the right position , no blockage etc. - running brad penn oil. - Are you running an unmolested stock MPS? It seems similar to what I have seen, and how I find the engine wants to run. It should be richer than 14 when you are heading up a hill though. I have 2 non leaking MPS's. the one i am runnint was resealed and set to factory specs by Scott in NH(who''s son just bought the 944). he has a wavetech and callibrated it. after installing it, i was having severe hunting, and it was definitely too lean, so ive been gradually tweeking it but before the A/F meter was installed, so it was more by feel and engine response. i increased richness across the board until it quit hunting and would idle decently(consider all thoer things are taken care of- no vac leaks, timing set, etc etc) so it really is running pretty good now, when warm it idles at @ 950 with lights on , maybe 1000 without, very smooth. i was going to take a peak at the plugs too again just to look at color etc. |
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