Stock M20 on a Mustang Dyno

[Komzorz]

Thought you guys might like some results for a bone stock 2.5l m20. My engine has about 86k miles on it, I'm pretty pleased with the results. I made 2 more HP but 10 less TQ on the first pull, this was the result from my second pull.

My buddy took a couple videos, he said he'd get them to me at work on Monday. Click for fullsize version.

[jlevie]

If those AFR numbers are from a properly working wide-band sensor, the engine is running way too lean. Valve burning territory actually.

[Komzorz]

Nah, nothing was hooked up to my engine. Bottom three stats are just whatever the dyno puts out when nothing is hooked up!

[digger]

yeah no way it would make those numbers if the AFR were actually in the 19.x but worth checking to what they are. is the line choppy because of no smoothing or is there an ignition issue?

[Komzorz]

It must be the smoothing value. Most of the guys at the dyno day were making 2-3x as much power so I'm guessing the line ends up looking tighter when it travels a bit further upward.

[brody]

yeah no way it would make those numbers if the AFR were actually in the 19.x but worth checking to what they are. is the line choppy because of no smoothing or is there an ignition issue?

The filter value on a mustang is 1 to 99. Notice its at 15 which is nothing. Also the mustang is way more accurate compared to a dyno jet for fine fine changes. That would be smooth as a babies bottom on a DJ on its lowest filter.

~145 is what we always used to get from a stock m20 in good "old" shape.

[jlevie]

The ripple in the curves is most likely to be from insufficient ignition advance for the fuel used. A stock engine wants 87 octane, using 89 or greater can cause that ripple.