This bugged me a bit so I checked with the SPA discussion group and Bruce Underwood, the current president, says the Jett muffler is acceptable for SPA use. Bruce encourages everyone interested to become involved with SPA of course and notes that several individuals are currently using this type of equipment.

Thanks for the follow-up on that Stripes........ much appreciated.

Bob

Well, this thread has been full of great info. I'm glad we were able to get a more indepth look at the Jett Engineering Co and their products.

Now, this is slightly off of the path, and really doesn't belong in this forum.....but, I recently found a web-site where a US company is making scale, functional replicas of vintage engines (automotive and aeromotive). They were recently featured in an engineering magazine I subscribe to. Their next project is to build a funcitional replica of the P-51 Rolls Royce Merlin engine. My understanding from the article is that the aeromotive engines are actually used in model airplanes as well as static/dynamic displays.

I hope you enjoy.
http://www.replicaengines.com/products.htm

hb,hp and kraft engines are now made in the usa.I have bben a fox and k&b fan since my controline days.Ido admit to owning some os and webra and supertigre engines but since fox came out with the mark x carb i use them on my twins and multi engine planes.the os engines i have seen lately do not impress me like the old fsr series.and super tigre is now made in china.I hat that term used around here keep in box for k&b.when i was running ducted fans the k& b 3.5 and 7.5 were the engines to use.just use a nylon beasring retainer bearing and no problems.had my 3.5 turning 24,500 rpm on 10 % nitro as it had a .40 size carb a rpm rod and a robart mark 4 pump never a lick of problem