ORIGINAL: rctom
The 3mm TOC-53 has an excellent muffler, sound level is reasonable and they are well built, TIG welded and polished.............lower front corner of the muffler is angled, means that I have not yet seen a plane where the stock TOC muffler won't fit completely inside the cowl........... (why isn't it right in the first place, how hard is that to do?) ........ the TOC-53 definitely was smoother,
The 53 and the DA are the two that I don't have, so I forgot the 53's muffler's attributes, which I agree with, slipped my mine, but a reasonable sound level is subjective. Sunday morning at 9:00 start your 5 HP lawn mower and your 53 see which one gets the interest of you neighbors. I had to touch a Honda generator once to see if it was running, that was quite, so quite is doable. 53 is very smooth, I like the three bearings.
The 57 timing issue I can't agree more.