Well, I'll give a data point of one.
Back in 1985 or so, I had a IO-320 that dyno'd at 181hp. During that
era, TCM cylinders could vary 8-9 per cent. Lycoming cylindersw could vary
up to 17%. An acceptable matching would have all within less than 2%.

I haven't seen it first hand but I been told by reputable sources that the
latest generation of PMA investment cast cylinders are within 2%. And that
generally these will show on dyno's, 3-5 % higher HP figures on the
average.

regards,
Kent


"MikePalmer" wrote in message
news:y4hhe.10190$D91.1571@fed1read01...
Light Plane Maintnance had an article on porting and polishing in the
May
issue, and it was written by Mike Palmer.
If you are Mike Palmer, why are you asking again

I was asked to rewrite the story from a user's perspective. The article
I wrote in LPM was from a mechanical perspective. I didn't supply any
user feedback in the LPM article. I'm asking for it now.

and why don't you use you're own email address?

Because I don't wish to get spammed by the spambots that troll the
newsgroups.

You can email me at the mppalmer at a o l . c o m address (without the
spaces) if you have input for the article.

Thank you,

Mike Palmer