I have tried the macs pipe and the Jett muffler on my 55AX both are ok but I have this on a GP Patriot and I think it needs to go faster. Where can I find a real tuned pipe for this motor?

Thanks

Macs does not make a real tuned pipe?



IMO the .55ax is not a speed engine.................

Yeah, if you want speed, the engine is what to replace. Use the MACS tuned on a .61.
The 55AX is a great engine but it's ported for turning larger props slower. About 13,000 is about max design.
You could select a smaller diameter, higher pitch prop but that may not make the bird faster.

Maybe a jett muffler would be a better choice?

Mac's makes lots of tuned pipes http://www.macspro.com/tunedpipes.asp They are about the only game in town if you want a tuned pipe in the USA.
Other pipes come from Europe if you want to go that route.

Unfortunately the OS 55AX is tuned for larger props at lower RPMs. The engine is bored out about as far as they can go, so the ports are more shallow restricting the engine on how well it can breathe. Thus although a tuned pipe would offer a small improvement in performance, you aren't going to get much more out of the engine. If you run the engine in its power band it does quite well. So you could go with higher pitched props instead of trying lower pitch props and peak RPMs out of it. You could tune the pipe for a higher pitch prop that stays within its power band and it would perform pretty good like that.

I would suggest a JETT tuned muffler or a homemade Mousse Can muffler that has been tuned. Mousse can mufflers work really well on the 3D planes too.

The Patriot prop jet plane has fairly thick wings to give it a wide performance envelope and less of a tendency to tip stall, etc, but it causes more aerodynamic drag though. Also the fake side intakes have a lot of drag too. To get more speed, one has to build the plane sans fake intakes and thin down the wings in the process too. Plus you need retracts on it as well. So you won't be getting lots of speed out of the plane unless you really overpower it with a Jett or Rossi .60 or something like that. But that depends on if you can get the engine to fit into the airframe or not. The small frame Jett .56 might be the way to go too. I think Jett quit making the small frame .60 as it was a touch too big for the crankcase size they were using. A Rossi .53 is another good choice too.

55AX ...... open carb up to .330 radius crank entryway to crank hole, raise exhaust port to around 175 try to get around .100" difference on the transfer. Run the Jett muffler and put a 10x9 prop on it. should be good for around 14,700-15,000

I guess the question was in regards to what one can do oneself in order to get more power?
I.e. what would you have done without your engine guru?