Many years ago, when flying pattern, I used to use Mac's and OPS muffled pipes. Times have changed and I'm in the market for a new pipe for my YS .60 roundhead short stroke engine. Any suggestions? Why? It will be screaming its brains out on an oldish ballistic type pattern model. The faster the better. Light weight and good throttling are mandatory. TIA

I'm currently running my YS 61 AR with a macs pipe and header turning a 12x12 APC prop at around 9500 RPM

If you want to try something different... take a look at Just Engines over in the UK. The purple multi-chamber pipe works pretty well.

The Mac's quite pipe actually performs great. Worth trying.

Unless you can scrounge up a Hatori 605 or 650

Thanks, Bob and Matt. I'll keep a peep open for'em.