Thanks for providing that information folks.
Island...... send Dub and Email....... he may have gotten an order mixed up and send the 4-40 muffler by mistake.
[email protected] The muffler is the same... some are built with 4-40 holes for use on TT, OS and Webra engines.
The info provided above is correct. The SS muffler is tuned for a bit higher RPM band, typically 17-19K rpm, where as the standard Jett-stream muffler kicks in somewhere around 15K, and runs best between 16-18K rpm. Jett SJ46 and SJ50 engines respond best with this turning ground rpm over 16K rpm. As noted, prop selection is important with the Jett mufflers. The SS muffler works best on quick airframes where the engine can easily unload, and where using smaller 8.5-9" diameter props is practicle.
Dub sells a "Sport Q-500" combination that is a SJ-50 with the q-500 muffler. Works well for most of these speed ships.
Strykaas, your engine selection depends a great deal on the aircraft you select. If you choose an aircraft suitable for the FIRE configuration, providing that information when ordering the engine is very useful. Dub can provide a tuned pipe system (pre-tuned) and test run the entire setup before you receive it. He will also tell you the RPM the pipe is tuned for, and recommend a few props that will work best in that RPM band.
You can use the FIRE configuration on a Patriot if you wish. Run the pipe down the fuselage side. I noted a few nice photos of a King Kobra with a YS RE on here.... same sort of layout. I would not suggest the high timed engine noted above...you need more prop on the patriot. But in general, the performance gain you get with the FIRE over a standard side exhaust engine is minimal, and I would recommend the SJ-50 for the Patriot 40.
For true speed with whiplash/DD and other RE configurations, Dub can provide a high-timed FIRE 50 that will simply amaze you. Its a bit less user friendly (takes a run or two to learn the needle proceedures). But thats just a bit of practice.
Of note, Dub generally does not generally sell the SJ-40 any longer. The .40 engines are only available in racing versions since they are required that size by rule. Main reason, is the SJ-46 cost the same as (less than?) the 40, it turns a 10x6 better, and is better suited for sport flying applications. That said, and of the Q-500 .40 engines can be ordered with the sport 2-needle carb if desired.
Bob