vertical grimmace

My Feedback: (1)

OK, I just ordered a rossi header. I figured i would save my muffler and know I had enough length. It is pretty cold here anyway so i guess i can wait. It seems, anything I achieve at this point will be pretty uneventfull considering what has been strapped onto the front of this thing already. It is more about getting the most out of this Rossi setup I believe. I know it will still be quite fast.

earlseaholm

Well, Dubb fixed me up with one of his new .56LX hot rod motors with all I need to put it in a Sundowner. [8D]
He says that it runs with the 60LX.
It should be interesting how this one works. COLD up here in Montana, so will have to wait till it warms up.
Earl
AJ's Dad

ALO 111

I have a OS 90 fx in mine wonder what difference a tuned pipe would make.

freakingfast

My Feedback: (3)

Usually a gain of at least 1500 rpm over the stock muffler if you are running the correct range prop to begin with.

If you are running a 12X8 APC @ 11500 now it should be 13500 on a tuned pipe.
(at that point a 12X10 may be better to keep it in the power band, with a pipe.)

Or how about a 11X12 APC at 12750 on pipe.

vertical grimmace

My Feedback: (1)

Hey Earl, never seen you post in here. I was the long hair, california looking guy, that sold you the TA 152 book back when we were flying combat.
I got to fly with Ron H. at the Warbirds over the Rockies this last summer. Hope all is well.

Rich

envallm

Which pipe would I put on the O.S 91FX and is it the same pipe for the new 95AX?

freakingfast

My Feedback: (3)

They can use the same pipe and header, but the header tuned length you end up with may be different. I used a Mac's marine muffled #1369 (for higher nitro- peak power) because I had it on hand. It was a bit small if was going to use it in a marine application where you need more volume but it worked out fine in my low 15% nitro medium rpm 91FX aero engine.

If were you, I would go with the aero version however. http://www.macspro.com/tunedpipes.asp Either the muffled tuned #1290 or tuned 1190 (LOUD).

The "quiet pipe" is usually better for broad range 3D power, not as much for top end speed.

Look under side exhaust headers but don't miss "special application headers" for ideas on engine/pipe positions.

You will need the 90* pressure fitting #9051. Just drill a hole to fit and feed the stem into position from the inside on a thread or wire with a knot in the middle so you can hold the stem and pull the wire back out from the inside. I use red Locktite, but do a dry run first to see if it will tighten and air will flow through it (elbow screwed down too far). You don't have too much working time with Locktite.

This engine has a very nice large flat power band. At 13700 and up the carb and internal restrictions limit power, so it's best for economy, longevity, and power to prop and pipe this engine so it's not over the 13700 mark in the air and around 11000 to 12500 on the ground.

Yes, I know it's rated at 2.8 hp at 15000.....FORGITABOUTIT. It's not worth it up there.

If you want a bit less power, (about 1000 rpm boost) there's always the Jett muffler. Work involved to install is a wash, but the Jett is more inside the cowling and you don't have a tuned pipe down the side of the plane.

Note: the Mac's one piece black muffler is not high performance but rather a very good better than stock muffler replacement.

earlseaholm

Hi Rich,
I still have the book, but no combat anymore. My son, AJ, did pretty well flying combat for a few years before he decided to go pylon racing.
National Champ in both. [8D]
I always told him he was lucky I wasn't there - would kick his ass. ;-) His comment?? Bring it on Pops.
Good hearing from you - take care.

vertical grimmace

My Feedback: (1)

Funny thing now Earl, I compete and fly in scale mostly. I am getting redy to build a 114" Ta 152 now, as they fly so well.

Eganwp

My Feedback: (1)

Now try a 10x8 APC on that 55ax. That's what I run on my OS 55ax. Turns 14,200 RPM on 10% Omega and hauls my Super Sportster 40 around at over 110mph. I run the $15 Tower Hobbies .46 pipe to gain 1000rpm on the top end. 2nd favorite prop was the 11x7 MAS S2 on stock exhaust w/ or w/out baffle.

Eganwp

vertical grimmace

My Feedback: (1)

Rossi header showed up today. Now I have all I need to get this thing rollin'. I will just have to go run the thing and get the header the right length. I sure wish I knew of a good starting point length, so I do not waste too much time.

HELLFIRE989

Hey guys been quietly following this thread for a little bit and decided I will pick one of these planes up. The question I have is what kind of speeds are you guys recording and with what engine setup? I am interested in the 75ax or 95ax with a pitts muffler. Lets hear what ya got.

Cheers,

Jason

earlseaholm

My Sundowner should be here next week!! [8D]
Ordered it from Central Hobbies on Thursday!
The new Jett .56 is mounted on my Q-500 for now and break in later when it warms up.

Iflyglow

My Feedback: (79)

Anyone try a Tower muffler yet with there .46-.60 (Evo .60NX) or a full length tuned pipe.

TopGanJa

Hey Bob, and everyone else,never posted here before but have a few questions if you have the time,

I used the same setup in the sundowner theBob has, with the jet stream muffler, and the exsaust exiting out the bottom. I havent flown it yet, but my question and concern is do you have a heating problem inside the fuselage. Meaning, does the heat from the muffler make it hot in side the fuslage. i was thinking about cutting out the spot at the bottom of the fuselage and the extra slot used for electric setup to create more airflow and less heat inside. I was wondering if this was a good idea and wanted to ask you what you have done before i cut into my plane? will the heat from hte muffler creat any problems inside, or does the radio equptment not get effected by the heat?
Thanks again,
Kristian

vertical grimmace

My Feedback: (1)

I now have mine ready to fly, Rossi .67 with full wave pipe. I am starting with a 10-9 APC and it is turning a modest 14,500. It feels and sounds good but I would like to get more out of it. I may need to go down in pitch one. We shall see. Maybe even adjust the header length. I went under the knife a couple of days ago but feel pretty good. I want to try and get in a test flight tomorrow.
I also will be flying it with a brand new Hitec Spectra 2.4 ghz module in my Futaba 8U radio. there will be a whole bunch of new stuff in this plane. it should all go well I believe, just not as fast as I would like.

Iflyglow

My Feedback: (79)

I suppose I should post it in this thread too since it will be powering a Sundowner.

vertical grimmace

My Feedback: (1)

Is 2.5" where the CG is working out with this plane? I woul djust like to verify where it has ended up with those that are flying one of these.

earlseaholm

Been working on my Sundowner this weekend it is close to ready to go!
Now all I need is the foot of snow to melt and warm up. [>:]
It has been awhile since I have built an ARF I am impressed with the quality of this one.
The thing went together very nicely.
Here are a few pics with the new Jett .56LX in it.
Dub said this one makes the same power of the 60, so this one should be a fast one.

Ebuli

Hi Earl,

Yes, they dont make Jett .60LX anymore so I ordered a Jett .56LX for my SD. Could you please post those pictures again with higher resolution, those are too small to actually see the installation details

earlseaholm

OK
If you haven't already - check out jettengineering.com and check out Mike Helsel's Sundowner. I basically copied what he did.
As you can see - I have a T in the line from the tank to the needle. I put a fuel dot in the cowl, but I am going to have to figure out a way to get to the line from the needle to the carb so I can pinch it off (or close the needle each time) when I fuel the bladder tank.
Still some details to work out.
I am pumped!! It is going to be in the 40's all week. The foot of snow should be gone this weekend.
Test flight time!! [8D]
I will post some more pics when she is finished.

vertical grimmace

My Feedback: (1)

I got my test flight in today. Balance was 2.5" back from L.E. at root. Seemed to be pretty good. Rossi .67 with full pipe turning a 10-9 @ 14,500. I would honestly say I was getting around 100 mph just from experience. The plane flew very smooth and handled nicely. Moderate aileron response but it did roll well. It did require quite a bit of down trim for some reason, but I did not look to see why.
This was also my first flight with a new Hitec Spectra module. I used a 7 channel Optima RX. This was installed in a Futaba 8U TX. Worked great.
Now I will just start fine tuning things and most likely lighten the prop. I need to try a 10-8 or even a 10-7. I had an 11-6 with me and it would turn that up to 15,500, which is pretty respectable. This will be a good candidate for our club sport race we have. It should be a fun experimental test bed.
No surprises what so ever. Flaperon may help landings but it certainly acts clean on final and it is wise to lose all of your energy early as it will coast a long way.

summerwind

Earl,

Now that is a Puuuuurty engine, and u can hear it screamin already.
it's next on the list once the flight reports on it's performance.
are you using a Bubble Jet tank?

earlseaholm

I am using a Tettra bladder tank that I purchased from Central Hobbies here in Billings, MT.
I took the fuse to the store to make sure the tank would fit, which was handy.
I am fortunate to live in a town that has two of the larger mail order RC stores in the country Central Hobbies and Heli Proz.

My other toy

summerwind

..........i didn't know Jett made engines for the hot rods too

thx for the reply, and yeah i'd be totally broke, divorced, and living in my truck if i lived near Central Hobbies.............