Well the ones that look like Hatori are. JE have many type of pipe tuned, quite with some tuning and quite. They differ dramaically indesign and function.
Listen, why not save yourself a heap of trouble and use your .61LA in the Hog and in it's place run your .91FX. Then you'll have plenty of power.

bla bla,
I am talking about the 60/90-sized "purple pipe" and nothing else. They have many other pipes too but me and my friend are using the purple pipe on Irvine and MVVS engines and the performance is very good and the throttle response is NOT on/off. The throttle response is actually very linear so they can be used on a 3D or pattern ship.

What engine and pipe are you using? do you have a picture?

Well if he's happy Flyer95 theres a good chance you will be too.
I'm sure these pipes are more than good enough... JE sells hundreds of them.

My 91 FX is installed now in my not maidened yet Corsair.

So,
that's why i am searching for increasing power in the OS 65 LA.

I wonder if it's a simple tuning problem -- is it adequately leaned out, for example?

BRITBRAT,
I second your observation with the issue of a incorrectly asjusted needle valve.

No tuning problem though!

Kostas, I'm sure that you mentioned it somewhere, but what kind of prop are you using? -- pitch, diameter, manufacturer & # of blades?

I am using an APC 12x7.
With this prop my 40size plane has good vertical climb but,not unlimited.
Will i switch to an APC 11x6 and a JE tuned pipe?

Kostas,


Read my post #25 again!
Your engine is not in proper working order.

Get it repaired and you will not need this pipe, since your plane is way over-powered as it is.

Why you are saying that?
I think i sent you a pm for the running of the engine!

Kostas,


Yes, you sent an E-mail to me, but the first post in this thread (see below) states you are getting only 9,120 RPM, instead of the expected 11,000 RPM.

This performance is unquestionably inferior to what this engine should give you.

Get it fixed, before investing any money in trying to re-acquire the performance that you should have had from the start!

In the meantime, remove the muffler baffle & try an APC 12-6

Dar, as you well know I have ny LA .65 converted to Diesel, sometime today I'll put the glow head back on it and run it with a ProZinger 12x7 and let you know what I get. At the same time I'll check the port configuration, if it has two intake ports like the LA .46 I don't see a tuned pipe doing much for it. Also, would you take a look at my Fox .46 vs Fox .50 thread and give ne some advice on that pipe, Thanks I'm a total greeny when it comes to pipes.

Dave,


I believe both the .65 and the .46 have the boost port.

Only the .40LA does not (the .40FP did have a boost port).


BTW, Kostas is using an APC prop, which may have a load that is different from the Pro Zinger.

I put something in the Foxes thread...

Picture #1 is the front of the cylinder, the exhaust port is barely visible, poor picture taker.
Picture #2 is the back, there are only two intake ports.
Picture #3 shows the exhaust port which is canted about 45 degrees CW as are the intake ports. My particular LA .46 has a third intake in the back of the liner but there is no corresponding passage in the crankcase.

What are you going to prove us torque wrench,with these pics?[&:]

Dave,


I don't understand...
Why would OS bother to make an expensive extra port, it they don't bother to make a corresponding bypass...

What he is suggesting is that your LA, with a single transfer port & a single boost port, is probably not a good candidate for a pipe -- which was previously noted.

There is some problem with your engine that is limiting its output. We don't yet know what that problem is -- but a pipe won't cure the problem.

Is the cyl head sitting squarely on the block (not cocked) & have you checked the cyl head bolts for tightness? Have you checked the back-plate for tightness? Is the carb firmly seated & sealed at the base. Does it idle smoothly & transition smoothly?

Have you looked inside to see if a casting flaw is partially blocking a transfer passage? Is there a piece of machining swarf in a transfer passage?

Is the sleeve installed correctly (not backwards) in the block?

Thanks Brit, My numbers with the stock baffled muffler and a ProZinger 12x7 running on Fox 5% nitro are as follows
With a ? #3 plug 10,323 rpm
Fox idlebar plug=10,531 rpm
Fox Miracle plug=10,691

The head being cocked, it happens, I fried the piston ring in a black Merco .61 because of that very thing. Like a Moron I gave it to friend who discovered the head being crooked and got a ring from Frank Bowman and now he has fine engine that he flies a lot.

His cylinder liner should be lined up OK, it has a cold rolled steel pin in the block that indexes a notch in the liner phlange.

Dar, I will look and make sure this is the case.

Everything is OK with this engine from idle-full throttle.
I must mention though that i have 5-6 tanks of fuel through it right now (12oz).
Am i done with the break-in?
It idles very good.
So,i must also mention that when i am running it rich i see bubbles come out of the backplate.
Is this a problem?
Should i tighten the screws?
Or is the excess amount of fuel that comes off????[]

Patrick,


The port arrangement in OS LA engines is such that the transfer ports and the exhaust port are angled, in relation to the engine's center-line.
I.e. the exhaust port is not straight to the right of the engine, but to its rear-right.

The transfer bypasses are rotated accordingly; rear-left and front-right.

Although the outside of the casting (see photo, silvery engine) shows a bulge where the boost bypass should be; at the front-left, Dave says there isn't such a bypass...


So it is only two transfer ports; not one plus a boost port.

Oops!
Double...

Please discard...

Kostas,


This engine should not expel bubbles, or leak, from its back-plate, in any case.

Make sure the bolts are tight, but not over-tightened.


I don't know how it is sealed to the crankcase and the parts list does not show a gasket, or an O-ring.
It could be a sign of the reason your engine does not make its full performance.

No,it hasn't a gasket,just the backplate (nylon).