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What can ya do? - 7/24/2003 8:56:28 AM   
Razor-RCU



Posts: 5294
Joined: 3/21/2002
From: Ramona, CA, USA
Status: offline 		I have a Cermark F-20 that started with an OS-61FX (got it that way..)= whale- Then I tried a Tuned pipe= whale Then I got ahold of a Rossi-60 and full pipe... Better but nothing special so-

Here is the beached whale-

Oh yeah- What should I be taching: Rossi-60 Full pipe, MA 11x7, Powermaster 5% nitro-? I think she was @ 13K...

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< Message edited by Razor-RCU -- Jul 24 2003 4:04AM >


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What can ya do? - 7/24/2003 9:30:09 AM   
ChuckAuger



Posts: 5134
Joined: 12/5/2001
From: Pampa, TX, USA
Status: offline 		Well, you left out the option I use on Rossi 60's...increase the exhaust duration to 160~164 degrees and actually get it on the pipe.

People think Rossis are "hot" engines, but they almost all have 148 degree exhaust duration, and that ain't "pipey" timing.

Go up to 160~ 164 and you will gain another free 1000~ 1500 RPM's, set the pipe accordingly, and have fun.

If you are not comfortable doing this mod, send it to me and I'll do it for free and pay return shipping.


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Sir- - 7/24/2003 10:49:04 AM   
Razor-RCU



Posts: 5294
Joined: 3/21/2002
From: Ramona, CA, USA
Status: offline 		Mr Auger,

To be honest I don't even know how to do that ... Is that in regards to the angle of the header?

I would love to have you do the mod. for me, but I would insist on paying for all shipping and your time-

Do you need the engine/header/ and pipe?

I can't even figure out the pipe...

Let me know if your serious, because I can have it out of the plane and in the mail pretty quick

I REALLY would like to run the Rossi-60 properly, one guy at the field said I was not on the pipe at all- but it looks like a quiet pipe so it was hard to tell-

Thanks in advance,
james


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What can ya do? - 7/24/2003 4:57:34 PM   
MMallory


 

Posts: 1115
Joined: 12/11/2001
From: South Plainfield, NJ, USA
Status: offline 		James,

While you are waiting to retime your engine you might want to work on cleaning up the airframe. If you don't have retracts, install some. Add gear doors, seal hinge lines, smooth out anything that even looks draggy. Next you want to use a speed prop. That 7 or 8 pitch isn't going to give you speed with large low-rev engines. You need a 10 pitch minimum. Try a 10x10. If you use this prop you will need more runway to build up speed before rotating. Once you are in the air use smoooooth turns to keep the speed up. Next, hold on, have fun, let me know when your knees stop shaking after the 1st high speed pass.

Mark

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What can ya do? - 7/24/2003 5:41:53 PM   
Rudeboy



Posts: 3256
Joined: 12/9/2002
From: Bejing, BELGIUM
Status: offline 		Raising the timing is no problem if you have a little patience, steady hands and a Dremel...

Maybe you could even go a little further... say 170°?

Chuck, have you ever grinded on a cranckshaft to change the induction port timing? Them cilinder liners are pretty soft, and so are cast alu engine housings... but cranks are hard... how do you do them?

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...I think it needs more power...

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What can ya do? - 7/24/2003 6:29:19 PM   
ChuckAuger



Posts: 5134
Joined: 12/5/2001
From: Pampa, TX, USA
Status: offline 		Razor,

Yes, I'll do it. It takes less than an hour counting the time it takes to put it on the test stand and check it out.

The actual procedure involves removing a slight amount of metal from the upper edge of the exhaust port in the sleeve. If you look in the exhaust port, you'll see about an 1/8" of brass hanging down into the exhaust area of the case.. If you remove some of that, then it allows the pressure wave the pipe creates to ram a little bit more of the un-burnt fuel-air mixture back into the cylinder before the piston closes the port. That's what a pipe does anyway, but by increasing the duration, you allow it to do it's job a little better. Only drawback...you now have to run a pipe, always. If you put a muffler on the engine after the mod, all it will do is allow that much more un-burnt air-fuel mixture to shoot out the exhaust and performance will suffer.


Judging by just looking at your header/pipe set-up, I don't think you are fully tuned. Ought to get a lot more than 13K on an 11X7, too. When the pipe is set, it should sound rich and blubbery, then really leap up in RPM when it comes on. You'll know it.

If you would rather, I can send you a modified and fully broken in Rossi 60, you can swap engines, decide if you like the modded one better or not, and then decide if you want to mod yours. That way you can "try before you cut" and see if this will be enough of a performance increse to warrant carving on your engine.

Rudeboy,
Actually, the chrome in the top of the port is the hardest thing to cut. A tungsten carbide spiral cutter won't touch it, but will cut away the steel of a crank, no sweat. The only thing I have ever done on a crank is increase the closing duration 5 degrees or so.

IMHO 170 degrees is too much on an engine turning less than 19K or so.


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Rossi 60 - 7/24/2003 7:21:05 PM   
ewspears


 

Posts: 242
Joined: 9/22/2002
From: Ocala, FL, USA
Status: offline 		Razor,
Better take Chuck up on his offer! That's about the best deal I've ever heard of!

If I were approaching the problem with your equipment;
I'd raise and eyebrow the exhaust to 164 degrees duration.
Clean-Up and blueprint the rest of the engine flowpath.
Adjust the squish band clearence so I could use 15-20% Nitro
Set a two cone Macs Pipe at 16" (Glo Plug to end of Converging Cone)
Use APC 10X8 and 15% fuel, Expect 16500RPM on ground and considerable unloading in the air.

I Guaranteeee!!!! It won't be described as a whale


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Yo, Razor.... - 7/25/2003 11:33:09 AM   
Flyboy Dave



Posts: 13511
Joined: 3/20/2002
From: San Bernardino County, CA, USA
Status: offline 		....send Chuck the motor and the pipe..let him wave
the Magic Wand over the whole thing....

....if it won't crank after he gets through with it....

....time to go to the Goodie Store.... :

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What can ya do? - 7/25/2003 11:40:43 AM   
tkigar



Posts: 271
Joined: 11/28/2002
From: Littlerock, CA, USA
Status: offline 		Better yet..........I have a better idea........sell me the darn plane and buy your self a turbine LOL oh ya......I still dont know how to fly and I got a garage full of planes and stuff.........anyone heading to the desert any time soon to show me how not to crash ????? I am tired of the wife looking at me with crashed planes LOL Bring that whale to my garage and lets go get you a real jet LOL Revver Bro #22 Tim


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