Sorry to offend you. I have a Ryobi type 31 that started life as a Lawnboy. It is stock and does an 18-8 just a little over 7000. I'm sure it would do 7400 with just a 11mm carb? On the Lawnboy, the muffler was already rather open with a single 1/2" outlet. I replaced the lawnboy as a weed whacker with a Ryobi in 1998 and the Ryobi still runs fine.

What prompted the comment about the DLE-30R was the statement about making a needle bearing aluminum rod for a Ryobi. If you start dumping a lot of money into one, you may as well buy an engine that runs pretty good as is.