run-in AFR
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run-in AFR
to those who frequently run engines in on the dyno with a wideband o2 sensor in the exhaust, how rich would you say is bore wash territory?
I have a number in mind, but i'm not sure If i'm being overly cautious (anything richer than low 13's with no load on the engine should be shut down)
am I far off here?
I have a number in mind, but i'm not sure If i'm being overly cautious (anything richer than low 13's with no load on the engine should be shut down)
am I far off here?
Re: run-in AFR
If you are worrying about fuel washing lubrication off the cylinder walls put some 2-stroke TC-W in the fuel.
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Re: run-in AFR
Any number is kind of arbitrary. What fuel are we talking about? Ambient temperature? Compression ratio? Are we talking idling, 4000rpm? You could have an engine with a 295@.050 Cam be lean at 13:1 and barely run in that idle to 4000 rpm.bentvalves wrote: ↑Sun Jan 19, 2020 9:59 pm to those who frequently run engines in on the dyno with a wideband o2 sensor in the exhaust, how rich would you say is bore wash territory?
I have a number in mind, but i'm not sure If i'm being overly cautious (anything richer than low 13's with no load on the engine should be shut down)
am I far off here?
Like tuner said, if you think you're washing cylinders, add some 2 stroke TCW.
Re: run-in AFR
How much 2 stroke TCW would you add per gallon of gas?mt-engines wrote: ↑Mon Jan 20, 2020 7:06 amAny number is kind of arbitrary. What fuel are we talking about? Ambient temperature? Compression ratio? Are we talking idling, 4000rpm? You could have an engine with a 295@.050 Cam be lean at 13:1 and barely run in that idle to 4000 rpm.bentvalves wrote: ↑Sun Jan 19, 2020 9:59 pm to those who frequently run engines in on the dyno with a wideband o2 sensor in the exhaust, how rich would you say is bore wash territory?
I have a number in mind, but i'm not sure If i'm being overly cautious (anything richer than low 13's with no load on the engine should be shut down)
am I far off here?
Like tuner said, if you think you're washing cylinders, add some 2 stroke TCW.
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Re: run-in AFR
I would be looking into how unnecessarily smooth the port wall finish is in the Intake ports along with the shape at the upper back of the valve bowl and only use the 2 cycle oil as a temporary crutch.
You can cut a man's tongue from his mouth, but that does not mean he’s a liar, it just shows that you fear the truth he might speak about you!
Re: run-in AFR
12.0 is about the limit for us. Plenty of ignition timing is required to keep egt's down also.
Carlquist Competition Engines
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Re: run-in AFR
speedtalk really needs a "like" button in other peoples posts that one can click.
the icon could appear as a trophy, a thumbs up, a fistbump, or a checkmark icon.
the icon could appear as a trophy, a thumbs up, a fistbump, or a checkmark icon.
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Re: run-in AFR
thanks to all who posted in this thread. ALL SUPER HELPFUL.
however, one post really hit the nail directly on the head.
best,
bent
edit: there was a close second as well.
however, one post really hit the nail directly on the head.
best,
bent
edit: there was a close second as well.
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Re: run-in AFR
Like the thumbs up/down symbol in the top right corner of a post?bentvalves wrote: ↑Mon Jan 20, 2020 6:44 pm A trophy icon for very helpful input would be best I reckon.
Felix, qui potuit rerum cognscere causas.
Happy is he who can discover the cause of things.
Happy is he who can discover the cause of things.
Re: run-in AFR
Thats whats nice about efi and wideband control. Once it fires up on the base map, it ends up correcting to target air fuel
On systems that dont have that ability, on a new motor, if its in the mid 13’s or leaner on gas, i feel ok. If its richer or way lean over 14.7, i stop and adjust fuel
On systems that dont have that ability, on a new motor, if its in the mid 13’s or leaner on gas, i feel ok. If its richer or way lean over 14.7, i stop and adjust fuel