K-Jetronic mixture control tuning

Half a turn is WAY too much, if we are talking about the same screw. I do it 1/16 of a turn. Even 1/8 of a turn can bring you from too rich, past the "sweet spot", and too lean.
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+1!!
Wow, that looks like a little four-banger unit

Breifly, you'll need a gas sniffer, Gunson or other, up each tailpipe. Adjust each bank to w/in factory spec's.@ idle--1% to 2% CO using 3mm T-handle Allen wrench adjusting from lean to rich (CCW to ClockWise). Be sure you're getting full power to the plugs...each & every one of them (an 11 cyl. car still runs pretty good, you know ). Mine's at 1.5% but I think it should be nearer to the 1% zone (but don't burn a piston ).
Adjust your idle & balance the banks via vacuum gauge connected to the line between the WUR & intake plenum gooseneck. Iirc, my understanding is that the 'huge' Allen screw on the gooseneck should be screwed in all the way & adjusted 'out' to fine-tune if you can't balance the banks via idle screw.
If you don't have the FI WM, try to secure one

 

+1

 

I bet you can find a guy near you who can it perfectly, if not 10 guys. The Peninsula and South East Bay still has a concentration of old school mechanics, who have no trouble with this.

 

Half-turn's too much at a time! You won't believe how little of a tweak (twitch) brings it in the the "sweet spot"
Get the analyzer / V gauges & avoid the dread!
http://www.ebay.com/itm/Gunson-Gastester-exhaust-gas-analyzer-tester-/280681199112?hash=item4159e73608&item=280681199112&pt=Motors_Automotive_Tools&vxp=mtr

 

From what I have read (does that make me an expert?) you will hit peak power output at a mixture that is really too lean to be good for the engine.

 

Bill

I am not sure what a 5-gas tester would do for you. There is only one screw to turn! Everyone adjusts for CO. There is nothing you can do for NOx except buy a different engine!

Bruce
The Gunson units do the job but they sure are touchy to get "zero'd". Mine drifts for nearly an hour before I feel comfortable to believe the readings. I pre-warm the engine and it is cold by the time the tester is ready to go to work. I use it and believe it, but you must be patient.

Bill
You said you quit testing at 110 C oil temperature. If you did all the other tests while it was below operating temperature the data is meaningless.

Ken

 

Like Ken said, there's only 1 CO mixture screw for each bank...plus these V12's don't have computers so you're basically adjusting the richness to achieve the 14.7 to 1 air to fuel ratio. You can play around w/ratio a little bit, otherwise HC's & NO's will fly off the chart.
Go down about half way on this page for the exhaust gas graph:
http://www.automotiveu.com/performancetuningpt2.htm

It's a simple process, you'll see. You don't need a special mechanic to do this job.

I noticed the touchy zero-ing in process too but got mine to w/in tolerance after some fiddling, around about the time the car was fully warmed up & all rad fans hummin'.
It was a great primer for the CO adjustment procedure. Turns out, the CO adjustment was easier than the Gunson.

+1

 

Turns out, the CO adjustment was easier than the Gunson.
+1

 

Our cars are pre-lambda, so that won't help. Plus, the 5 gas analyzers are used on cars with computer controlled engines...the 400's don't have them. The Gunson or similar CO analyzer is all you need, some feel the Gunson is a toy & not as accurate as the more pricier ones.

I thinkin' Ken meant 100 deg. C (which is 212 deg. F---boiling), & that's fine.
Oh, & don't blow that motor, that'll be a $30K mistake you'll kick yourself for.

 

you need a gas analyzer, someone must have one near you

 

I could use a couple of brake fluid reservoir caps

 

I said 110 degrees C oil temperature and oil boils at a LOT higher temperature than that!

I watched my gauges a bit closer this weekend on a 400+ mile trip to Gettysburg and back. At a steady 70 degrees F ambient I get just about 100 Coil temp. At steady 80 mph I am up to 105 or so. I know in summer at the same speeds both temperatures would be about 5 degrees higher. Oil temperature always seems to be load dependent.

On the other hand water temperature at the same conditions was pretty steady at 90-95. In summer it would be 95-100 C. Water temperature only seems to go higher in stop and go traffic or if you slow suddenly have a long hard drive at higher speed. Three fans are really needed in summer. I had one dodgy fan 2 years ago and temperature pushed a lot higher at steady 70 mph. Hence I rewired fans for reliability. With a 12 psig radiator cap water will not boil in system until about 116 degrees C but actually higher with glycol in system.

 

I have a set for you

 

Sorry for the lack of description Ken. My thinking was that at 100 C, any moisture in the oil is steamed off. I've always used 100 C as the target temp. (when motor is to be fully warmed up), do you still stand by your 110 C recommendation?
After reading AEHaas's Motor Oil 101 & following his recommendations,
http://ferrarichat.com/forum/showthread.php?t=136052&highlight=%22motor+101%22
I found that my h2o runs around 80-85 C & oil runs around 90 C (unless sitting in major traffic back-ups which I generally avoid @ all costs), oil pressure 'around' 5~5.5 bar, & that the fans don't run as much. I have to be dumpin' fuel or sustained 160+ klicks to reach the typical temps (h2o @ 90, oil @ 100) while oil press. remains the same except when reaching redline.

 

Bruce
My point was that if you started taking readings below about 90 C, those readings were less meaningful. You stopped at 110, but where did you start? The sum of other posts is that 90 to 110 is pretty normal with higher numbers at high load or high ambient. If you took readings with oil temp down at 50, 60 and 70 they can not compare to those at 90-110.
Ken

 

Understood, thanks!