RE: Turbo-Jett muffler for AX75
Hey there... great to hear from you. Sure, the turbojett actually works very well on the OS75. Depending on the prop and your available space - you can use either the "61" size or the "90" size version. Dub can provide adpaters for either. The 90 size is better for lower rpm if you are running a 13" or 14" prop. Just specify the engine when ordering. Dub will get ya set up. Bob
Posted on: 9/11/2012 1:36 PM by Author "bob27s" in the forum "Jett Engineering Support"
http://www.rcuniverse.com/forum/fb.asp?m=11225325

OT - RCU log in difficulties anyone?
Hi Friends.. Past week or two i have had a ___tch of a time getting into RCU. Virus software and firewall stuff go nuts logging in or getting to some parts of the site. Anyone else having this issue? Figured I'd ask here since most of you know me Bob
Posted on: 9/4/2012 9:52 AM by Author "bob27s" in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=11217013

RE: 60LX
Sorry for the delay... my virus software kept telling me it was getting hit from RCU so I took a break from it. :) You can get the 56 in there, yes - but fitting the exhaust system will be a huge challenge. Plan accordingly...
Posted on: 9/4/2012 9:29 AM by Author "bob27s" in the forum "Jett Engineering Support"
http://www.rcuniverse.com/forum/fb.asp?m=11216988

RE: sport 40 muffler
Hi... Sorry for missing this post. I trust you got the information from Dub you required. The standard Jett-Stream muffler would be the one typically used for the SJ-40. Bob
Posted on: 8/20/2012 6:11 AM by Author "bob27s" in the forum "Jett Engineering Support"
http://www.rcuniverse.com/forum/fb.asp?m=11199511

RE: .56 back plate mount screws
Dub can send you longer bolts if needed. Email him jettengr@sbcglobal.net Or also I recommend McMaster Carr (not expensive, will have them in a day or so). Bob
Posted on: 8/20/2012 6:10 AM by Author "bob27s" in the forum "Jett Engineering Support"
http://www.rcuniverse.com/forum/fb.asp?m=11199510

RE: quickie 500 type arf?
Take a look here ... www.matneymodels.com If you want conventional, build a Pit Bull or Zoomer. Glass/foam Easy build if you are not racing it and just want a good, fast toy.. either are hard to beat. Other suggestion is the new ViperDog. SEMI ARF you can use a stock Viper wing (and tail if you wish) and use the new fuselage. Pleanty of room inside for standard servos. Most importantly... reasonable cost. Matney can provide pre-sheeted wings for any of the planes too. Bob
Posted on: 8/16/2012 12:02 PM by Author "bob27s" in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=11195953

Model Mania 2012 - Airshow - Elyria, OH Aug 18th.
As event director of the Lorain County Radio Control Club, Inc., I wish to draw your attention to the included flyer promoting our upcoming airshow, Model Mania 2012. This year’s event shall be presented on Saturday August 18th, 2012 at LCRC’s flying facility located on Murry Ridge Rd. in Elyria, Ohio. The show begins at 1pm and runs until approximately 4pm. For more event details and driving directions, spectators can visit our club website at WWW.LCRC.ORG or they may call 440-315-4633 for more information. Model Mania is our club’s annual public air show and exhibition, and our way of giving a bit back to the community. The show features demonstrations of all aspects of the sport of radio control aviation, including scale replica aircraft, sport aircraft, trainers, racing aircraft, and helicopters. Featured aerobatic and specialty acts will be presented throughout the day. There is non-stop action and fun, and something to thrill everyone. This is a very family oriented event, and everyone is welcome! Refreshments will be available for purchase. Donations in support of the event will be accepted. Spectators are encouraged to bring along a chair and sunglasses so they may relax enjoy the show. The Lorain County R/C Club is a not-for-profit organization, and a chartered club of the Academy of Model Aeronautics, which promotes and supports the sport of radio control aviation in the Cleveland area. Our club helps promote aviation and aeronautics through educational and demonstration programs for local schools, scouting troops, and community groups. The club is comprised of over 110 men, women and children from ages 6 to (over) 80, all with a common enjoyment of the sport and hobby. Bob Brassell President, Lorain County RC Club
Posted on: 8/16/2012 11:40 AM by Author "bob27s" in the forum "Events, Shows and Fun Fly's - Airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=11195924

unavailable for support till Aug 14
Greetings friends... Some travels will have me in limited availability to provide a quick response here. I will be back to availability Aug 14th. You are welcome to leave a post ... others may help out as well. I can get back to you with specifics at that time. Bob Brassell
Posted on: 7/31/2012 11:03 AM by Author "bob27s" in the forum "Jett Engineering Support"
http://www.rcuniverse.com/forum/fb.asp?m=11176039

RE: OS AX 46 needs more power
What prop, plug are you running on it now? Can you post a photo of the installation also ? Keep in mind.. . Q-500 speed is not ALWAYS the engine. If you are actually racing, flying has a LOT to do with it. If you are just messing around comparing straight line speed... then need to work on the prop setup. The engine is what it is trick is finding the prop that makes that particular engine/airframe combination happy.
Posted on: 7/23/2012 11:30 AM by Author "bob27s" in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=11165950

RE: RCPRO Club 40, bubbless tanks after 2012, etc
Many of you folks know me... most may not... but I thought I might add my comments. My local club and one other here in the Cleveland area started up Club 40 events locally in 2010. So this is our 3rd season. Doing well here so far. To prove a few points, my plane was built 100% stock out of the box. I used everything. The intent was to demonstrate to all of the new racers that special equipment does not win races. From the box, the only thing I did differently was seal the ailerons and elevator gaps, and I did not use the shrink-wrap for pushrod attachment (old fashion thread and glue worked fine). After the first flight, I changed the wing bolts (put 1/4-20 in), Removed the spinner and substituted a spinner nut, and I swapped out the stock fuel tank and replaced with a bubble-jett. Why the tank then.. if my intent was to fly purely stock.. ? Simple... the front of these planes (and it varies often from plane to plane) is not rigid. They shake. In my case this situation, and the stock spinner, were generating fuel foam and bubbles. Caused the engine to run poorly, impossible to get a good needle. The bubble tank was a 100% simple, fool proof method to resolve that problem. Does the bubble tank provide a performance advantage racing these aircraft? No my friends. Does it prevent blown plugs and a toasted engine ? Most definately. Just a simple way to eliminate at least 3-4 big variables in the fuel system. (not to mention avoids a mess .. the handful of stock tanks that I have seen crack or leak). I have set up other pilots airplanes, stock tank with fortunately a more stiff front end on the plane.. and they flew great and engines ran well. If the engine is lean, it will still go lean in the corners with a bubble tank. It does not provide positive pressure greater than muffler pressure. If you think running 2-3 clicks leaner in the turn will win you the race or that the bubble tank causes people to win or go faster ... it is time to get more practice flying the race course and prove yourself wrong. (in fact I have demonstrated to more than few people, that setting rich and letting the engine unload sometimes is faster). It is ALL about corner exit speed. Many of you will agree. Bob Brassell
Posted on: 7/18/2012 1:16 PM by Author "bob27s" in the forum "Club 40"
http://www.rcuniverse.com/forum/fb.asp?m=11160194

RE: Carolina Speed Rally...Again!!!
[quote]ORIGINAL: vicman I would love to post more pics here but RCU seems to be doing the time-out thing again.[:@] There is a similar thread in RCG with pics and comments if you are interested. Thanks for the nice words G. Bob, That plane was a real hummer. I only flew it a few times other than the OJA race where it held fast time for a while. That poor BSE .40 took a lick. [/quote] I had a decent crash June 30th. Our Club 40 race ... after finishing the heat.. was just flying level down wind to go around to land - then, it just locked up. Fortunately throttled back to about half. Did a beautiful slow pitch up and slow roll... then pitched "up" into a absolutly vertical strike into the soybean field. You can tell it went in dead vertical by the damage to the leading edge and wingtip ribs. btw.. appeared to be a switch failure. Everything else checks out. Switch had a broken wire at the solder joint after crash. (72 mhz, but it just shut off do not think it was interference). Kinda sucked though.. I had won each heat, and just needed to fly the Gold Main and that new TT40 was mine .. [&:]
Posted on: 7/6/2012 5:41 AM by Author "bob27s" in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=11145049

RE: Carolina Speed Rally...Again!!!
[quote]ORIGINAL: vicman Something wasn't right in the universe thats for sure! Some of the guys went out Sunday and were looking at the crater and started laughing that there was even a wing crater. Pretty serious hole for dried clay. [/quote] Wow.. that is impressive! well done :)
Posted on: 7/5/2012 8:51 AM by Author "bob27s" in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=11143889

Holiday week
Wanted to wish everyone a happy and safe July 4th week! Also... the NATS are coming up .. vacations, and such. I will be here to check in and provide support when Dub is away. Please drop a note in the forum or leave me a private message. Also available by email - Enjoy the celebrations ! Bob
Posted on: 6/29/2012 12:45 PM by Author "bob27s" in the forum "Jett Engineering Support"
http://www.rcuniverse.com/forum/fb.asp?m=11136805

RE: enya 45 CX...JettStream Muffler available?
hi... my apologies for the delay... Yes, Dub can provide a muffler to fit the engine. If you can double check and verify the bolt hole spacing that would be useful information. But we have a pretty good database of adapter and bolt spacing info on hand. Boost typically is about 600-1000 rpm (ground rpm) above what you would see with a stock muffler on a typical 10x6 size prop.
Posted on: 5/15/2012 6:40 PM by Author "bob27s" in the forum "Jett Engineering Support"
http://www.rcuniverse.com/forum/fb.asp?m=11082318

RE: Need help identifying Sport Jett Engine for Bearing Replacement...
My apologies... I missed this one somehow. The crankcase on all of the engines were marked with the engine size, a number, and Dub's signature. If the case had been replaced, then it might not be marked. Yes, Dub makes engines from .40 through the 60L in the small block size case. The Sport Jett .40 was used for racing evenings for several years, and the SS-40 was based on that engine too. So finding a jett .40 is not difficult. Yes, typically most people would use a .46 or .50 for sport plane use. As for bearings - easy to find. The SJ-50-50 use the same bearings. Unless it is one of the 1993 version engines - Version #1 from long ago. If you have a photo of the engine you can post, I might be able to assist. Bob
Posted on: 5/1/2012 6:50 AM by Author "bob27s" in the forum "Jett Engineering Support"
http://www.rcuniverse.com/forum/fb.asp?m=11063912

RE: Jett Stream muffler question
[quote]ORIGINAL: pencon If no ones tried matching the ports how can you say it doesnt matter? I notice a huge difference in the port sizes from the muffler to my Thunder Tiger36.I guess the question is will it run any worse if the muffler is ground out to match? [/quote] We have tried experiments, and others on their own have opened the ports too. It will not typically run worse, no. So no harm experimenting. But doing so typically does not increase performance.
Posted on: 5/1/2012 6:45 AM by Author "bob27s" in the forum "Jett Engineering Support"
http://www.rcuniverse.com/forum/fb.asp?m=11063906

RE: .
OK :) Hope ya got the information you required. Anything else, please .. feel free to post or email Bob
Posted on: 5/1/2012 6:41 AM by Author "bob27s" in the forum "Jett Engineering Support"
http://www.rcuniverse.com/forum/fb.asp?m=11063901

RE: Engine choice for EU1A
Hey there.... Thanks for writing.. Well since sound is indeed an issue - FIRE 90L will be your best bet. I recommend having Dub configure and tune the pipe too. You will need to be specific on the header since you need a slightly "up" canted header, not just a riser header, as I recall (last EU1-A I built was a long time ago..) A LARGE quantity of the noise we observe from our aircraft comes from the prop. The exhaust/pipe/muffler is only part of the battle. Mac's quiet pipe, have him set it up with an 12x9 prop - this is a long pipe setup. The advantage of the full pipe is you can tune for the RPM target and prop you need. Tuned for the 12x9 - you will have pleanty of room to play with various props. Should put it in the 12,000, 12,500 peak rpm range. One of the challenges with the EU1-A is the pipe tunnel size, and another is the prop ground clearance. The plane was designed for 11" props, and fairly short pipe layout. So plan ahead when you lay out the pipe tunnel. You will want a few different props to work with from 11x9, 11x10, 12x8, 12x9 find one that gets you the balance of sound and performance. I'd love to see the TigerTail when you have it completed - send photos :) Bob
Posted on: 4/18/2012 7:51 AM by Author "bob27s" in the forum "Jett Engineering Support"
http://www.rcuniverse.com/forum/fb.asp?m=11047075

RE: Custom connecting rod
[quote]ORIGINAL: Rudeboy Hi Bob, Simple question: would Dubb machine me a couple of custom rods if I very kindly asked him to do so? [;)] I've got an old Webra DF engine here that was renowned for throwing rods apparently... there were aftermarket 'rpm' rods available in those days... I'm sure he could make me most anything, for a price... [:D] [/quote] Sorry for the delay..... Drop him an email ... give him the existing rod dimensions too if you can. It may be very similar to the SJ-90 Rod ... in which case it would not be difficult at all. Bob
Posted on: 4/7/2012 1:33 PM by Author "bob27s" in the forum "Jett Engineering Support"
http://www.rcuniverse.com/forum/fb.asp?m=11032079

RE: Sundowner 50 goes 499mph!!!!!
capable of bark 2.0 !
Posted on: 4/2/2012 5:59 PM by Author "bob27s" in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=11025805

RE: Would SportJett .46 Be Good for This....?
Hi Glenn, Sorry for the delay.. You can use the SS40 in the small sundowner. However, take some time to really look at the installation. The 40-56 size engines and muffler installation in the larger Sundowner works out great and can be kept internal. On the smaller 36 version I have not attempted that with the .40-.56 size engines. It may be a tight fit. If you have to mess with the muffler installation a great deal - or need an extension probably not work as well as you might think. Again, take the time to plan out an installation will it fit, and can you modify the airframe to accomodate the jett-stream muffler properly ? If so, then sure, you would be ok with the SS40.
Posted on: 3/27/2012 7:15 AM by Author "bob27s" in the forum "Jett Engineering Support"
http://www.rcuniverse.com/forum/fb.asp?m=11016920

RE: Sundowner 36 + Sport JETT .50 or.60LX FIRE
can you get the muffler installed on there?
Posted on: 3/22/2012 6:33 PM by Author "bob27s" in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=11011285

RE: H9 Jackal 50 Prop Jet
[quote]ORIGINAL: jetpilotrich Strangely, I start all my Jetts with a hand flip of the spinner and they start right up! The long nose spinners make it easy. Do you know off hand what is the break-in prop for the 56LX? 9X7? Someone made a electric jackal hitting the 180s.... wonder what speeds the Jett 56s have been putting out? Rich [/quote] Yeah, 9x7 is good.. 9x6 too
Posted on: 3/15/2012 7:21 PM by Author "bob27s" in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=11001924

RE: H9 Jackal 50 Prop Jet
[quote]ORIGINAL: jetpilotrich Hey Bob! I have been distant from the hobby but am getting back into it with a vengance! Just finished up my Jackal W/Jett 56 package as well.... I also used a bubbless tank and electric retracts/doors. I am now producing High quality HD videos and posting them on youtube under the name RCINFORMER. I will be putting out several videos on the Jackal shortly discussing Jett motors and Tanks. Both you and Dubb may find them usefull for promotion and knowledge for customers on the Jett site. The videos will be similiar to but superior to the SU-27 video I made for you guys back in 2005! good to see the video is still available.... even now i still get email about it. All my contact info is available on rcinformer.com Anyway its good to be doing more R/C again.... talk with you soon. Rich Baker [/quote] Rich!!! Good to see you buddy... Yeah everything like that would be outstanding to have available. I still pass around the link for the 2005 video ... often enough people wonder if the engine is hard to start or if it idles :) Will keep an eye out... Bob
Posted on: 3/12/2012 1:33 PM by Author "bob27s" in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10997314

RE: The
Nice :) [:D][:D][8D][&:]
Posted on: 3/12/2012 1:28 PM by Author "bob27s" in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10997309

RE: T-38 (.40 to .50) size...........
Wow... That would be great to get into production mode again...... Bob
Posted on: 3/12/2012 1:22 PM by Author "bob27s" in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10997298

RE: Would SportJett .46 Be Good for This....?
Thanks for writing... Short answer is certainly the SJ46 will work great in the Sr Falcon. Quite honestly it is one of the best sport engines ever designed. Very versitile. [&:] Jett engines are powerful and some are designed for speed applications, but the Sport Jetts are very user friend sport engines. Great idle and transition, easy to start. On the SJ-46, prop it with anything from a 9x7, 10x6, or 11x5 and it will run great. Important to follow the run-in instructions (on a test bench, not the airplane). And it is important to make sure your fuel system is good reduce any fuel foam risk. On the Sr Falcon, get the engine some time with a 10x6, and then try the 11x5. That would give you the best balanced performance. Having said that.... the OS55 is a darn good engine. In fact the OS55 combined with a Jett Stream muffler will give you amazing performance quite a few of those flying out there. Bolts right on, no hassles. Great power, and props like 10x8, 11x6, 11x7 are good choices. In fact for some of the classic pattern and vintage pattern events this has become the weapon of choice. I trust this is helpful [;)] Bob
Posted on: 2/23/2012 4:21 AM by Author "bob27s" in the forum "Jett Engineering Support"
http://www.rcuniverse.com/forum/fb.asp?m=10971820

RE: WHY!!!
[quote]ORIGINAL: daven I agree with you on this one, I wouldn't want a performance motor from someone that had treated it that way. If they didn't care about the case, did they care about the break in? How did they run it? etc... [/quote] Agree here entirely
Posted on: 2/20/2012 5:32 PM by Author "bob27s" in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10968249

RE: Jett muffler Red vs black on ASP XLS 52
[quote]ORIGINAL: airraptor One day when i get some time i will set down and take pictures of the mods we do. Did you widen the top a little also? you should open the carb up more if you know how if not find a bigger carb like one of a 60 or something. I think the ASP carb is .290 with the big spray bar in it. with the Stock ASP spray bar the carb should be closer to .330-.340. now if you open the carb up to much it will not close at idle and have a 6,000-18,000 motor lol. Some heli carbs are bigger also. One way to see if you need to open the carb more is how the needle is. if you have a narrow range of adjustment like 4-6 clicks rich to lean then need a bigger carb. We shoot for a half turn rich to lean. this is all with a muffler pressure tank and the tank is close to the engine. If the tyank is a bit farther away then stay smaller on the carb as it will draw better. Jett mufflers Blue 14,000-17,000 Red 14,500-17,500 Gold 16,500-19,000 Black quickie 18,000-20,000 Black Q-40 I think is 24,000-27,000 Now these are not the numbers from jett these are just from our experience. Dubb would'nt sell you the Q-40 one if you told hime hat engine it was for. there are exceptions also. the main thing to remeber is everything is a combo once you get all performing at its best it will be storng. The Super tiger 45 once worked on will spin a APC 9x8 at 18,500 on the black muffler but with the red one on one of the engines it spun the same prop at 18,800. we do all port and crank work by hand so a little twitch in the grinding bit may kill or add to an engine. I did forget to tell you on your exhast port once you raised to .4-.5mm you should angle that upwards at around a 15 degree or so. This will help get the exhaust out easier. just think like a three angle valve job. the 3 angle valve job has better flow then a nice rounded edge. [/quote] Yeah those are about right number wise... Keeping in mind these are the "46" size versions. Black muffler (Q-500 muffler) should be 18,500 or better typically Gold Muffler needs to be "over" 17,000 although launch at 16,000 is just fine. An important thing to remember with any of the muffler/engine combinations and was mentioned earlier the engine will unload and stage deeper onto the muffler in the air. With this, the engine will need more fuel. So always make sure you set the engine 600-1000 rpm down off of the ground peak RPM when preparing for flight. That is perhaps the biggest mistake people make with any tuned exhaust system. When in doubt, under-prop, and launch rich. It is easier to sneak up on performance than to rebuild an engine that burns up due to a lean/hot run. Also... I often get asked "how come the muffler inlet size is so much smaller than my engine exhaust?" "should I open up the muffler opening to match my engine". Short answer is NO. It is not necessary. In fact in some cases it will cause lost performance. The longer answer most engine manufacturers make really big wide open crankcase exhaust ports to save weight, not for massflow. If you look at more serious high performance engines over the years, you will see the smaller exhaust on all of them. Rossi, CMB, YS, Profi, OPS, Nelson, Jett, some of the older high performance OS engine .... several others too. It was more important to maintain transition from the exhaust port in the liner to the inlet of the pipe header or muffler. So as for bolting the Jett muffler with a "small" inlet onto your OS55 or similar not an issue. Works perfectly. Bob
Posted on: 2/11/2012 6:54 AM by Author "bob27s" in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=10953989

RE: js-30 muffler on a .36 engine
thanks for writing... Yep, the 30 size is the one you want. We use the same size on the BSE30 and BSE35 engines. Also on the BSE40L. Performace on your engine will be eye opening :)
Posted on: 2/9/2012 8:06 PM by Author "bob27s" in the forum "Jett Engineering Support"
http://www.rcuniverse.com/forum/fb.asp?m=10952191