run-in AFR

[bentvalves]

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?

[Tuner]

If you are worrying about fuel washing lubrication off the cylinder walls put some 2-stroke TC-W in the fuel.

[mt-engines]

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?

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.

Like tuner said, if you think you're washing cylinders, add some 2 stroke TCW.

[BobbyB]

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?

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.

Like tuner said, if you think you're washing cylinders, add some 2 stroke TCW.

How much 2 stroke TCW would you add per gallon of gas?

[mag2555]

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.

[BILL-C]

12.0 is about the limit for us. Plenty of ignition timing is required to keep egt's down also.

[bentvalves]

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.

[bentvalves]

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.

[bentvalves]

A trophy icon for very helpful input would be best I reckon.

[MadBill]

A trophy icon for very helpful input would be best I reckon.

Like the thumbs up/down symbol in the top right corner of a post?

[Orr89rocz]

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