Mudball3

I am thinking of building a Limit Q500 and mating it with a rossi 61 df engine. All I need to do now is find the right prop for that engine. Any help on that issue would be greatly appreciated. I was thinking maybe a 9x8 cf. let me know how far off i am.

Here is the link to that Limit Q 500 http://www.pylonworld.com/rc_pylon/q...imit_q-500.htm

Thanks for your help.

YUKONFLYR

A Q500 is a very small plane for a Rossi 61. Heavy engine that is rear intake. That would put the engine much forward of where it should be along with the prop about 2 1/2" forward as well. Balance would be an issue.

How about a Jett 60lx...its a 40 size engine that will fit on a Q500 and will turn some serious revs with small props on the black pipe?

Richard

Mudball3

I would really like to put this engine to use it has just been sitting around gathering dust. Is there any other airframes that would work with this engine.

Thanks much.

It doesnt have to be a q 500 airplane but I also dont want to sped a lot of money if that is at all possible.

Mudball3

I just want it to go really fast. Any suggestions on what kind of prop i should use

Thanks

MJD

My Feedback: (1)

8.2-10 CF speed prop or 9-10 APC perhaps? Perhaps a clipped 10-10 might be better in terms of hub strength. But a "big block" on the nose of a Q500? Doesn't worry me horsepower-wise but in terms of weight and balance. Perhaps if you lop a couple of inches off the nose. With the extra induced drag and balance issues, I wonder if it will go faster than a QM40 or 50/60LX small-block powered example. Hey, I guess someone ought to try it!

MJD

freakingfast

My Feedback: (3)

Dead on right, all of it!

combatpigg

My Feedback: (3)

If this engine is a runner, those high pitched APC sport props can let loose, even below the recommended 190,000/diameter formula. I would not try this project with a cheap ARF. One little hidden flaw in the ARF Q500 and you will need a shovel to retrieve whatever is left. The big Rossi would have you hacking into the plane and moving things around to get the CG and to get everything else that got moved back happy again. The higher quality reenforced Q-500 wings that are set up for the 160mph class would be the way to go, then just build your own fuselage

bob27s

My Feedback: (19)

Go to www.MatneyModels.com .... look up the Zoomer on the q-500 page.

This design may better accomodate the engine.

Basic kit is fiberglass and foam. Inexpensive, and affords flexibility.

Fiberglass fuselage.... you can position the firewall further aft when you build it. You will have to come up with a sturdy aluminum beam mount or build a wood mount (Id probably go the wood route, look how the Cermark F-16 mount is done). You can probably build a cowl/cover to keep most of the resulting engine opening enclosed. Pipe could be run down the side of the fuselage.

Keeps in the speed-spirit you are looking for, good flying plane, and will tolerate coming in a bit heavy with the extra engine up front.

Just a suggestion

The Rossi .61 fan engine was just a high timed pattern engine.
I'd suggest trying the 8.8x9.25 Q-500 prop. Should be about the right load.... no issues up over 20K rpm if it gets there.

Bob

Mudball3

Thanks for the info guys. Were can I get this 8.8x9.25 Q 500 prop.

I like the looks of that zoomer. Do you now how it builds fairly easy or hard.

Thanks much.

Mike Connor

My Feedback: (5)

Zoomer build thread.
http://www.rcuniverse.com/forum/m_64...tm.htm#6499138
Prop is an APC.

Mudball3

Hi I called Apc and talked with the tech guy and he said that the only prop that he would use was the 7.4x7.81C Q40 carbon.
He said that the larger 8.8x9.25 was going to be to big and that the engine would not be able to reach operating rpms.

What do you guys think. I dont know much so your advice is greatly appreciated. Will this prop make my engine over rev?

bob27s

My Feedback: (19)

Fred knows his props out there.

Id start with the 8.8" diameter prop. 8.8x8.5 up through 9.25. Find the one that gets the engine up to 20K rpm. The Rossi .61 an .81 both ran great at lower rpm in Byron fans. So they were happy in the 16,000-18,000 rpm range. Just set the pipe accordingly.

Consider a Jett .40 q-500 engine will turn an 8.8x9 prop upwards of 20K+ in flight (appx) the rossi .61 would be happy doing it too.

Id use the 7.4 prop on a .45 size fan engine, definately. The .61 has better power and more torque.

Mudball3

Ok thanks for the help and info bob.

freakingfast

My Feedback: (3)

The 8.8 and 8.75 diameter pylon props should be safe to 25500 max (air or ground) and I tend to stay away from N or NN (narrow) props, they seem to slip too much for me.
Betcha that Rossi 61 DF will like the new 8.8 X 9.25 at about 19500 when the pipe is set right.
on sale too:
http://www.pspec.com/details.asp?ProdID=47&category=6

Mudball3

Thanks for the info freakingfast. i orders some of the props 8.8x9.25. I have a tuned pipe but it is for a .65 to.91 size engine. Will this be to big if so what brand makes a good tuned pipe. The only one that I have ever really heard of is Macs.

Thanks

freakingfast

My Feedback: (3)

That pipe may work just fine. Some DF engines run one size up from normal. Try it.

Mudball3

I have been told different things when it comes to DF engines and I was wondering what % of nitro to run in this engine. I have been told that this rossi engine runs best on 5%. What do you guys think?

freakingfast

My Feedback: (3)

Do your testing on a stand, it's easier to work on and see what your doing. Fancy or blocks of wood, it all works.
Stay behind the prop arc.

freakingfast

My Feedback: (3)

That's a safe % to start with. I think 10% is the max with this engine.

Mudball3

Does anyone have any suggestion on were i could go or info on how to correctly adjust a tune pipe. I now that adjusting the overal length of the pipe in relation with the header and engine is the basic idea but from there i dont now much.

Thanks

freakingfast

My Feedback: (3)

http://www.macspro.com/tuning.asp
http://www.macspro.com/pressure.asp

Mudball3

Thank you very much.

Mudball3

I had noticed that some of you had said that you cant find a dominator kit any were. I found a web site that still has them.

http://www.roguerc.com/product.php?p...&cat=14&page=1

Mudball3

Does anyone know were i can get a wood fuselage and foam wing q 500 kit? Thanks

proptop

My Feedback: (8)

Check the Pylon Racing forum...you should be able to fine something there...