I built a mousse can muffler & was wondering about attaching it to my Macs Header, should I cut the header or leave it the stock length? I plan on installing it on my OS .46FX with a 11/6 prop. An article from Macs said to cut the header to 3.375" for my engine but I don't know if that is for one of there tuned pipes or if it's the same for the mousse can. Thanks

Go to the Mac's webpage and snoop around a bit. They have a whole article on the how-to's on tuning the set-up. It varies per engine/prop/fuel set-up. So...if you know what engine/prop/fuel you are using, and plan to stick with it, you can get the most out of your mousse can pipe...Mine work GREAT!

I keep hearing about these aftermarket pipes. Do you have Mac's website?

The MACS instructions are for their tuned pipe installations, not for header pipes alone. Leave your MACS header the length it came at, which seems rather long, but your not putting a MACS tuned pipe on the end of it. The mousse can acts as a low restriction muffler. It has very little if any tuning properties.

The mousse can muffler works very much like the tuned mufflers that come with Rossi, MVVS, Nelson and Jett motors. It's very similar in function to a header pipe on a 4-stroke. It helps scavenge your engine by "extraction". This is very different than a complete MACS tuned pipe (also known as an expansion chamber). A complete tuned pipe will send a positive reversionary wave back to the exhaust that helps prevent fresh fuel and air from being "over-scavenged" into the exhaust system. At the right RPM an efficient tuned pipe can actually give a slight supercharging effect. Because of it's properties the tuned pipes work well with engines that have long exhaust port timing. For regular sport engines with less than 165 degrees of exhaust duration the mousse can style muffler is actually very effective, especially when the header is left long and larger props are used, like 11x6's on a .46.

MHawker, you can find macs web at macspro.com The mousse can muffler is found at www.uoguelph.ca/~antoon/hobby/mcm.htm

would i be better off using a mousse can muffler for a TT. PRO 46 or a macs tuned pipe?

If you want to run 10 in. props and are more interested in top speed go with the MACS tuned pipe. If you want to run larger 11 in. or 12 in. props go with the mousse can muffler. It will accelerate a bit better and be a little easier to tune.