Ok guys what do I put my JETT Fire 60L in?
 

After jumping on the Phenom hype and being very disappointed with it my Jett Fire 60L rear exhaust engine just sets collecting dust. Need some ideas as to what airframe to put it into now. Having a hard time trying to find a good airframe to put it into bring its a rear exhaust engine. I do have a Diamond Dust setting around. If I were to put it into that airframe what modifications have you guys done to them.?

RE: Ok guys what do I put my JETT Fire 60L in?
 

Go with the Dust! Since it is impossible to get a Whiplash.

Next choice is the Screaming Demon, I have one that has not escaped the box, yet.

Make sure the pipe support and motor mount are in good condition.

RE: Ok guys what do I put my JETT Fire 60L in?
 

I cannot speak from personal experience but one of my club buddies had a Dust with a Jett 60 in it. It was very nose heavy, and would glide like a rock. After many flights the motor conked in a bad spot, and it went nose first into the road near the field. Very limited elevator control with that heavy motor up front.

RE: Ok guys what do I put my JETT Fire 60L in?
 

I have a couple of .46fx's, and I also have a 60LX SE engine and the 60LX is about the same weight if not lighter than the fx, the 60 is also smaller in overall size.
IMHO a Jett would be perfect for a Screamin' Demon, its either the jett 60 or the OPS 65 I have, in my next Demon.:D

RE: Ok guys what do I put my JETT Fire 60L in?
 

The 60LX would be fine but the 60L is too heavy for a DD or SD IMO.

RE: Ok guys what do I put my JETT Fire 60L in?
 

What are you guys on about? [sm=confused.gif] It's a small block and weighs pretty much the same as the 60LX, the SJ.40/.46/.50, and other .40's around which the DD is designed.. so I don't quite get your point. Sounds like the guy didn't know how to balance and trim his airplane. A delta that size will glide well enough to land safely at a pound more than his probably weighed. I'm soon ready to test fly a 4 pound Demon.

MJD

RE: Ok guys what do I put my JETT Fire 60L in?
 

That's why I specified "cannot speak from personal experience." That is what he had, and that is how it flew. I saw it fly many, many times. Don't kill the messenger MJD.

RE: Ok guys what do I put my JETT Fire 60L in?
 

I had it in my mind the 60L was a 60 size block but it is a 40 size. My mistake. It should balance without much trouble being a FIRE. A side exhaust 40 often requires lead in the tail to fly right.

RE: Ok guys what do I put my JETT Fire 60L in?
 

Oops wrong engine....late, need sleep.

RE: Ok guys what do I put my JETT Fire 60L in?
 

I wasn't intending to be snotty, that was typed with a grin. Maybe my sense of humour is a little left of center for some, no harm meant. Even if the airplane was really heavy, if it is balanced properly he would still have been able to pull the nose up. I wonder why he had such a balancing problem is what I'm getting at, the engine weight is normal for the aircraft. He sure wouldn't have been able to slow down for landings with that forward CG position. With the engine quit sure, the nose would go down as he'd never have the airspeed to do much else. It would be no fun flying that thing at all.

I'm surprised at how slow I can get my 3.3 pounder before it finally settles in.

My biggest worry with the heavier pig Demon I'm working on, apart from not grinding off the belly which is really not an issue on the grass, are the long "slideouts" with these belly landers - all the more terrain they cover looking for things to snag the leading edge. I cracked the LE on my original Demon last time out as it found something out there all by itself and bonked it mightily. Quick repair, and as I fiddled with its I realized I ought to strip it and recover it anyways sometime soon. The film's too "untight" for my taste.

I keep visualizing a pylon wheel in a little fairing underneath..

Mike, I find the Demons balance fine with a 4 cell pack behind the rear spar and a .50 up front. In fact with the West and pipe vs muffler, it was pushing the rear limit. Do the Dusts balance with similar effort?

MJD

RE: Ok guys what do I put my JETT Fire 60L in?
 

The Jett 60 is lighter than many 46 sport engines. I think your buddy messed up with CG and/or not enough elevator to flare.
I run a, on the heavy side, YS 45 RE's and the batteries(5 cell AA) are to the very rear of the servo compartment in a standard Dust and it flares great.
A real heavy OS 46VXDF engine on a clipped wing Dust requires the batteries, 5 cell AA or 2/3 A to be "built in" just to the aft of the rear spar (between the rudders). A bit hotter landing but very predictable flare.

Lead is a sin:)

RE: Ok guys what do I put my JETT Fire 60L in?
 

I can't think of a more natural fit than the Screamin' Demon for speed and simplicity.
I was never aware of any "end user" troubles with the little 60 until recently. Must have something to do with less liner mass to carry away heat as a contributing factor? Sounds like a great engine if it's run per Jett's specifications.

RE: Ok guys what do I put my JETT Fire 60L in?
 

As mentioned, when Dub says "L" -AND- "LX" he means the engine is some combination of stroked and bore to achieve drasticly more displacement than the physical block size and weight would normally have. "L" means LIGHT, "LX" means Light AND high port timing. There is an engineering wall that you hit when you start overboring two strokes. The more you bore it out, the less room you have left for transfer ports and the less room you have (proportionally to displacement) for your gas passage through the crankshft.
Given these constrainsts, some of Mr. Jetts L's and LX's are at the PINNACLE of engine power to weight ratio that I ever expect to see. Understand I'm talking about power to weight ratio, not power to displacement ratio,big big difference.
So for instance if I was bracket racing (warbird etc,) I can turn way more prop with a darn good 60 SIZED block 60 like a well set up Rossi or YS than I can with a Jett 60L, or LX. Now give me the standard Jett 60 and I'm back on a level playing field with those example engines (and I'll still chose the Jett every time!) BUT, now we are back to talking about engines that weigh the better part of twice as much as my beloved "L" -AND- "LX" Jetts.
I don't have the means to globetrot to national race classes these days, so I dont have any DISPLACEMENT rules limiting me, soo...., I stock up, design up, and build up, around alot of "LX"s and one favorite "L".
I'll give you guys a couple of examples.

#1) S.E. 60LX on a V-Max Q500, balanced the same as with the previous Nelson 40, and routinely turned an apc 8.75x9.75 D-1 @ close to 20,000 rpm on the ground set conservatively for flight (unloaded like a banshee in the air too). Absolutely the fastest Q500 I've ever seen.

#2)Jett .76L on funfly/3D planes. This is to illustrate the point of diminishing returns that I am trying to get across regarding overboring a certain engine case size drasticly; weighs more than one ounce LESS than an O.S. 46ax for example... conservative port timing, broad VERY even torque band, 1,800 to 14,000 rpm useful range, with the supplied Jett-Lite muf. it turns an APC 14x4W @ 10,500 (exactly the same rpm as a Saito 82 on medium nitro like the Jett runs), I run mine on the "60 sized" Turbo-Jett in cowl tuned muffler and that puts me to 12,000 rpm on the same prop on the same 15% nitro. Try to get that out of anything else that weighs about the same and still has a darn good throttle transtion!
Tomski, sorry to have digressed so far, butnone of it is off your topic, (I needed to give you some background on what can be achieved with overbored engines like yours)
Having said that; you are rear exhaust which is a huge plus, you have a Heck of an engine, if indeed it is an "L", and NOT an "LX" 60 my wild a@@ guess for starting prop on any decently setup Diamond Dust would be APC 9x9 / 9x10 , look for at least 16k on the ground for this app. with this engine. BUT identify the engine to certainty first, if it turns out to be an 60LX, your starting prop would be in the range of 8.75x9.25NN.

P.S. Bob 27 please feel free to Chime in!!!
P.P.S. Bob27 please feel REALLY free to Chime in!!!

RE: Ok guys what do I put my JETT Fire 60L in?
 

:D:D:D:D put it in a cardboard box and mail it to me! :D:D:D:D

RE: Ok guys what do I put my JETT Fire 60L in?
 

My experience is that the Dust and SD are similar when it comes to balance. Mine have always come out at 2 lbs 14 oz or less and tend to be nose heavy unless you have a tuned pipe extending to the rear.

RE: Ok guys what do I put my JETT Fire 60L in?
 

Yeah there is a noticable shift in CG with pipe versus muffler, I did not measure but maybe 1/4" or in that range. So far it looks like the .65 ver is going to work out fine for balance. The Stits covering adds extra weight behind the CG. And a lot of strength too, so I'll take the extra 1-2 ounces.

MJD

RE: Ok guys what do I put my JETT Fire 60L in?
 

Well guys it is a 60lxl fire and I just checked the weight of it compared it to my OS 46 AX without muffler and it is lighter. Is there any extra reinforcements needed with going with the bigger engine. Should I sheet the entire wing with balsa to help minimize the possibility of having a tear in the covering and blowing it apart at high speed? I though I read that some time ago.

Sorry Crazy4flight I am not in that good of a Christmas spirit. I think I'll keep it for now. LOL:D

RE: Ok guys what do I put my JETT Fire 60L in?
 

Tomski,

A D Dust needs only Ultracoat, Mnocaot is too thin.
Sheeting the wing only adds weight.

Make sure your overlaps are downwind and hinge gaps are sealed.

C4F

Oh, I would pay for shipping. [sm=bananahead.gif]

RE: Ok guys what do I put my JETT Fire 60L in?
 

CP:

Have two of the 60LX's and running them for over two years with typical Jett performance. One was eating plugs until the head button was changed, no problem with the other. The only gripe after 6-7 years of running Jett's is with the 60LX and its superior quality. The machining is so good, the head bolts tend to get loose after one or two flights, so I keep a torque wrench handy at the field. When the head gets loose and you replace a plug, the liner will move in the process and the timing is out of whack. Yes, could use some lock-tite, but I still follow Jett's instructions to the letter, a hard learned lesson.

If you have not owned a Jett engine at anytime in your life, any of them, you are going through life worse than a virgin. Missing one of life's truly wonderful experiences. Yesssss, love my Jetts!!! Have yet to try the 60LX on a 3D machine, but the 35, 50 and 90's have all been outstanding in this application. One flip start, outstanding idle and transition to power when you need it. Never a flame out, never. Even my electrics fail during flight once in a while. Ever see a Q-500 doing torque rolls?

Still the cheapest motors I own. Have yet to wear one of them out, now one over 7 years running strong. Thanks for the tip a long time ago, Chuck Roundy!!

RE: Ok guys what do I put my JETT Fire 60L in?
 

I haven't seen a D Dust blow up yet due to the wrong covering, but I'd sure pay to see it!
It would be a traumatic BOOM if it was inflated doing 180.[sm=lol.gif]

Always inspect and patch even the small holes!.

RE: Ok guys what do I put my JETT Fire 60L in?
 

The FIRE 60L and the FIRE 60LX weigh pretty much the same. The side exhaust weight is different, mainly because of the muffler - the regular 60L has a longer (larger) muffler.

RE: Ok guys what do I put my JETT Fire 60L in?
 

Ultracote will last longer...due to the bellylandings

RE: Ok guys what do I put my JETT Fire 60L in?
 

They are well thought out, so you don't need much if anything. Sheeting will make it heavy and weight is your enemy. Ultracoat/Oracoat is fine. I added a strip of .007 carbon as seen. Tri-stock in the corners of the bulkhead/firewall(DF pic.), gusset at the LE tube and motor mount juncture. Wick in some thin CA at the edge of the engine mount cut out and mounting holes to give some crush resistance. Use a thin strap with holes or washers on the bottom. The Kevlar mat seen is overkill. You may need to rock the engine a bit to get the muffler off the wing so you may need to make some thin and thick hard wood wedges for under the engine mounting lugs. I had to do this with a black head Webra 55. The "L" engine Jett muffler may even be longer and more of a problem.

RE: Ok guys what do I put my JETT Fire 60L in?
 

Roger.....Nelson head screws get tighter by themselves....;).

The only Jett I got is the sport .46. It doesn't turn a 8x8 much better than a OS.32, but it makes good speed with a 9x7 or 9x8. It spews black gunk out every run, but seems to be in perfect shape. It did 153 mph today on a Screamin' Demon with a 9x7 prop on 25% nitro and 20% oil.

RE: Ok guys what do I put my JETT Fire 60L in?
 

Check your muffler. My Jett 50 started spitting black exhaust and it turned out to be a crack in the muffler. I didn't know it until the muffler actually split in two. Black exhaust is usually aluminum rubbing. Something is either cracked or loose.

Blessings, Terry