Marco S.

Anyone already used the Sport Jett .50 Engine?
Is it worth the money spended it?

www.jettengineering.com/

Motorboy

There has not been some problems with the Jett engines. The Jett engines are well designed and machined with modern CNC tools to keep the engines high quality and reliable.

Gringo Flyer

My Feedback: (18)

Look through the speed planes forum and they are popular over there.

vicman

My Feedback: (10)

Smokinest engine I own. I wish I could afford several more. Awsome!

bob27s

My Feedback: (19)

No doubt you will find a few statisfied Jett engine owners in here

Any questions you have ....... feel free to drop me a note or post in here.....

Bob

SpeedBoy

Bob , I have a question , comparing the life of the metals from an OS Max-70SZ-H and a Jett BSE. 90LX wich of these engines will have a longer life ???? . Both supposing be running in the range 16K .

I make this question because I recently saw a thread in wich I found out the O.S develop 16,000 RPM with a 10x10 APC I think similar of the Jett 90 (please correct me if I'm wrong ) and I just wonder what will be the difference between them , of course besides the price .

Also if you know advantages or disadvantages will be very appreciated .

Thanks in advance.

liquid_TR

A guy at the field runs an OS 91SX-H heli engine with a full tuned pipe on a pylon racer, he gets about 15500rpm on APC 10x10 with 30% nitro. The problem is this engine wont rev much more in the air, because of its upper rpm limits.

But I bet a Sport Jett 90 will match or exceed 15500 with less nitro and smaller tuned muffler; and un-load a-lot more in the air.

Pathous

My Feedback: (12)

The rpm numbers on the Jett websight are minimum numbers the engine must make before it leaves the factory. I have 2 Jett engines a .50 and .40 Q500 both are excellent engines with tons of power. The 50 has incredible transition better than any other engine I own. The Jett will also outlast just about any engine out there they use true chrome and modern cnc machines. The engines are machined and assembled here in the U.S and test run before the get shipped.

Julian537

My Feedback: (9)

I have a Jett .50 and they are well worth the money!

bob27s

My Feedback: (19)

Either of the engines will last for many years ......... both are built well. THe only way to hurt the Jett 90 is a handful of lean runs.

I have no idea on the OS90 performance.... I know the aero version 91FX is somewhat conservative on crankshaft and port timing...... and although it is powerful, it props heavier and runs best around 13,000 ground peak rpm. I have never tried a 10x10 on it. Best prop I found was a 12x8, 11x9, 11x10. The real limitation on the OS91 is the bearings ........ a bit undersized for really trying to turn it hard.

The heli engine is higher timed, so with the right exhaust system it probably does run closer to the Jett 90 engine. The bearings, if anything, would be a limiting factor. The heli engines never see the prop shaft loads that an airplane does.

SpeedBoy

Thanks Bob and all you guys for all the info .

I didnt know jett engines eat fuel before you open its box . Kind of pre-break-in ???

bob27s

My Feedback: (19)

It is not really a break-in period. Should not be considered as such.

A new Jett engine owner still must follow the break-in instructions provided with the engine.

Dub runs all of the engines for three main reasons.

1) The engines are very tight when new. If the rod is going to break, it will break on the first startup when the engine is tight and cold.
- Usually they do not break, about 2 a year - but its better to find out before it leaves the shop.

2) Dub takes the engine up to full power on his "standard" prop to verify the performance.
- If it does not perform to specs, it does not get shipped.

3) Dub sets the idle mixture. Jett's low speed mixture is different than most, and this is an important step
- End user may have to make tiny adjustements (1/8 turn or so) as the engine runs over time, but no more than that.


The break-in period required at the engine owner's end is important for 2 reasons

1) It gives the engine run time under controlled conditions, at the right rpm, under a ligher load, and thus slightly rich.

2) It gives the engine owner the opportunity to understand how the engine runs, baseline rpm numbers, and a point of reference.


Bob

Sport_Pilot

Jett and Fox post the minimum number the worst engine leaving the factory should set. OS only lists very optimistic HP with no muffler and no telling what fuel, and no prop.

maxtenet

I have many engines and around thirty in the .40-.50 size. I have been using a Jett .46 on a Champion .45 and can say in 35+ years of flying it is without a doubt the best engine I have ever owned. Extremely powerful, incredible carburation and response. It has been stored every winter for about 6 months and starts right up with a flick of the wrist. I have barely touched the needle in ten years. Can't praise them enough!

Max

SpeedBoy

Excellent reasons Bob

Now I see jett engines are tested to the benefit of the own costumers and it seems is the only brand wich do that rigth !!!!

I've never had a jett engine but I'm considerig buy one some day and see by myself the results .

Thanks once again Bob .

MJD

My Feedback: (1)

YES. They are very high quality engines, and you get whay you pay for. FOLLOW THE INSTRUCTIONS, including running it in on a test stand. The test stand does not have to be fancy, just sturdy enough, and it will eliminate the variables that can and often do occur in an airplane installation.

Jett knows what he/they are doing, and they support their product very well.

MJD

Cyclic Hardover

My Feedback: (3)

Or going full speed down the back stretch and have the prop come off and spin upwards of 1,349,698.00rpms and break a rod. Simply fix and runs great.