bob27s

My Feedback: (19)

The question is a bit open because the header length is not really the key. You would have had to use this specific combination. Pipe length depends on a number of variables.

The measurment is the "pipe" length..... that is the length from the glow plug, along the centerline of the header and pipe, to the fattest part on the pipe.

As a start, measure up to about 13.5" with the marine pipe and the 10x7. That will put you in the general ball-park, with the pipe set just a bit long yet.

From there follow the pipe tuning proceedure on the Jett Engineering website to optimize for your selected prop and application. Works for just about any setup.

Keep in mind, the marine pipe is great for top end boost, but can cause issues with midrange and transition. Its not terrible, just something to watch for.

edit: uploaded an image for reference

thetrums

My Feedback: (22)

Thanks Bob 27s I kept cuttin and I am at 15,500 at 11". I am almost at the turning point of the header. Not quite broke in. Is that enough RPM's for this motor? Cannot cut anymore. I have one of your Jett, Jett Stream Muffler on its way. Which would be better?

bob27s

My Feedback: (19)

If the rpm kept climbing as you cut, and the engine remained well behaved (setting the mixture was easy and it throttles well) then you are about as good as it is going to get... especially if you have run out of header.

The best way to see where you are..... run it with one size larger prop, and one size smaller prop. See how the engine responds. Its the same as adjusting the pipe - you just force it to run another rpm, and you can see how it responds positively or negatively.

If it turns the larger prop with ease and is well behaved, the pipe may still be long. But in that case, just use the larger prop instead of cutting.

The jett-stream muffler will work nearly as well as a well tuned pipe. Its just easier - no tuning. Just bolt it on. Key with that is to ensure you prop the engine for the rpm range of the muffler.

Target your prop selection so the engine turns over 16,000 rpm. A 10x6 would be a good baseline to start with.

The muffler boost effectively (best) at peak ground rpm of 14,500 up to about 18,000. So a prop selection that hits this range and gives you the aircraft performance you want is what you want to find.

And yes, the OS50 loves rpm ..... 16K+ is good. Your 15,500 so far is good.

ke6gkc

"Hi, my name is Bruce Burgess and I am a Speed Plane Addict. I am just getting back into r/c.
I have been a Lover of Speed Planes for to many years,
and with the help of the Revvers Brother-hood I hope to
make my planes even FASTER !!!
Don't let my wife see this....I promised her I
would "tame it down a bit". : ( heh heh heh )

Signed Bruce Burgess 06/12/2008

Jack Stafford p-39 Jett 76 w/pipe
Building Screamin Demon Jett 50 FIRE w/pipe
Several Quickie 500s in process
Pictures soon

Flyboy Dave

My Feedback: (21)

....Welcome to the Brotherhood, Bruce....

....you are Revver Bro #223. [sm=teeth_smile.gif]

Rev on, my Brothers.

thetrums

My Feedback: (22)

Thanks again bob27s, you have been a great help.!!!!!!!

FASTCRASHER

hey brothers check out my new screamin demon...
just got her covered yesterday!!
hope to fly her very soon![img][/img]

bob27s

My Feedback: (19)

Looks great ....! No doubt it will fly as great as it looks...

FASTCRASHER

it does fly and and is very fast !!
heres what i flew yesterday.
the red and white one is a r/c guillotine

claytucker

anyone have success with the phenom delta besides razor...

evan-RCU

2000 posts!!?!?WQ!#%#!%

Took a step back to glow. First flights on a used F3D today, did not get on pipe so the numbers were horrible...

claytucker

Razr - You have the only video and good comments that I can find regarding the phenom.

Sadly, even on their web page they have some of the phenom models - posted that could not fly, like Crazy.

But the model looks so kewl that I really want to find out more

Have you seen anyone else fly them? Have you found any other videos? Any other success stories... How do you like yours overall? any idea of the speed?? How many rpms with which prop on the os 50sx??

Thanks

fossoman

Mines not as fancy as some of you guys but it does About 80MPH
http://uk.youtube.com/watch?v=HG9tGHyzZcQ

claytucker

purchased NIB (stored away by ebayer) a whiplash. Trying to decide on engine to match. Worried about price and launching. I have had a lot of fast wings and was thinking a nelson or q40 Jett. The hi revvinng engines should be a lot quicker then the 50 60 lx... Opinions. maybe jett will set up 50 fire to 22k+

never had a race engine, need help. Local RC store seems to just sell me the most expensive

claytucker

purchased NIB (stored away by ebayer) a whiplash. Trying to decide on engine to match. Worried about price and launching. I have had a lot of fast wings and was thinking a nelson or q40 Jett FAST. The hi revvinng engines should be a lot quicker then the 50 60 lx... Opinions. maybe jett will set up 50 fire to 22k+

110 mph on shark delta seems slow, reasonable optoins...

never had a race engine, need help. Local RC store seems to just sell me the most expensive

evan-RCU

Clay how many places did you post the same question? Why not just start a thread of your own???????????

ULG

Dear friends
I am a aeromodeller from India .I am impressed at speeds you guys are
achieveing in 40 to 70 size aircraft I would be very thankful if you can suggest
a good start up kit to reach atleast speeds above 1oo miles .Please syggest kit (40 to 60)
engin ,propeller , servo and anything you feel important to buy to get into
this kind of flying
thanking you in advance Udayan

vicman

My Feedback: (10)

I guess our answers would depend on what kind of experience do you have? What type airplanes do you like to fly? How much building do you want to do?
Quick and dirty cheap speed over 100 is any Q500 airframe and either a .46AX/FX , .40 or .46 TT Pro with standard radio gear. That's the easiest answer I can offer. If you want something diffrent please let us know.[8D]

ULG

Dear Vicman
Thank you for quick response. I am flying planes 40 to 120 size since last 6 years
i also am found of helicopters . i prefer flying speed or pattern flying against 3 d
At present high speed plane that i fly is GP patriot with TT 46 engin and futaba
9 cap standard radio set . I belive this aircraft does 70miles . I would like buy
ARF kit , engin 40 to 60 2S or 4S as you may suggest and others important
acessceries required. I am asking for details because in India it is not possible
to buy specific aeromodelling parts and i have to order most of it from US ,Singapore
or Europe and I would need to do the same at one go.Please sugest propeller
required and few that i need to keep in stock to try diffrent rpms
thanking you in advance udayan

vicman

My Feedback: (10)

I would step on my Patriot if it only did 70 mph!
Why not try a engine upgrade for the Patriot like a Jett .60 w/9x9 or 9x8 APC prop.
Are you thinking of going electric?

mk1spitfire

Hi I'm a speed addict and love the adrenalin shaking feeling you get from high speed flight.

My Flair Dara with westonuk 36v1

and Yt Mach racer with westonuk 50v1

plus some ones unknown hot delta, enclosed pipe which I LOVE

evan-RCU

Those are all yours? Wow!!! [sm=71_71.gif]

Strykaas

Not the third one

By the way, do you know if Dara 20 / Flair products are still available somewhere ?

mk1spitfire

Hi, I don't think so. I got this new Dara kit from someone who had stored it. The Plane flies fantastic. Loves the high speed,turns on a dime. Excellent glide. As quick as my weston uk magnum with 50v1 tuned pipe. It was for club 20 class but I beefed it with that hot weston uk 36V1 with 8x6 turning 22500.

Sadly a servo let me down and its toast. I can't bear to cremate the bits and would love to jigsaw the pieces back together again. I stuck a carbon spar in the wing which has held up but leading edge and foam inner mashed. front fuselage very bad.

Good luck searching.

Strykaas

I've already searched a lot. I owned a Flair Meteor 40 (from the .25 / .40 / .60 family). Same red polyester fuselage stuff, same tough wing construction (foam + obechi planking). It was toasted when a guy shot me down. I would love to build another one, it flew great ! I have already contacted Flair and they told me they will never put it back into production. Loosers. Those fuselages were very nice, a bit heavy, but so good looking.