does the evolution 61 have the same exhaust bolt pattern ans the OS 61SF/FX motor

lol...i guess im gonna have to get off my ass and do some work ...ill be back with results

It is likely that it is

The Evolution is a derivitive of the Magnum XLS 61 which is a copy of the OS 61 FX

These engines are all the same

<font size="4">O.S. .60 FP &amp; LA, .61 SF, .61 FX,.65 LA, .75 AX
Evolution .61 NT (not the .61 NX)
Irvine .61 (NEW - bolt through)
Jett .67L -.76L (not the .60L)
Magnum .61 Pro
MDS .68-.78 FS Pro
Thunder Tiger .61 GP, .61 Pro (bolt through)
Webra .61-.75 P5-H </font>

thanks W8ye,i verified it...they do have same exhaust pattern

Can anyone tell me how O.S. labels their mufflers?  I have two that say 744 with different bolt patterns.

Aren't the 61NT and the 61NX the same except for the head? I looked at the parts list and both were the same except for the head, that I guess is higher compression??? I tied to order an NX head (only about $6.00) for my 61 NT and they are backordered.

The 60NX is a bored and stroked 46, right? And all different?

You are Correct on the .60NX from Evolution.

The 744 came out in 1970's or so and was used on the 60/61 FSR line of engines, which had a bolt on muffler...then sometime in the mid 80s they came out with the SF (61)l.. that 61 used the same 744 muffler but has a bolt through pattern

Your list is not complete, you forgot the OS .91FX and the Leo/megatech .61





Sorry, I could not resist

Thnks for the education

P Laurence
<br type="_moz" />

And the Magnum/ASP XLS 91

But .91 engines tend to run hot when used with mufflers intended for .61 engines

My ASP .91 came with a muffler that the magazine review said was the same as for the .75 and the .61. Comment was that the small muffler drove the max HP down but increased the torque at lower speeds so that bigger props were most effective. I run mine on FAI fuel using speed shop methanol and Klotz Lubriplate castor/syn blend. 1700 rpm idle and 8400 rpm high with 14x8 MAS prop. Good transition and smooth running at all speeds. I may try larger diameter props just for Ss and Gs.

Quote:

ORIGINAL: spaceworm

My ASP .91 came with a muffler that the magazine review said was the same as for the .75 and the .61. Comment was that the small muffler drove the max HP down but increased the torque at lower speeds so that bigger props were most effective. I run mine on FAI fuel using speed shop methanol and Klotz Lubriplate castor/syn blend. 1,700 RPM idle and 8,400 RPM high with 14x8 MAS prop. Good transition and smooth running at all speeds. I may try larger diameter props just for Ss and Gs.

SW,


I believe Klotz call their series of synthetic oils for methanol based fuels [link=http://klotzlube.com/products.asp?cat=8]Techniplate®[/link]; not Lubriplate.

The MVVS .91 engine, albeit equipped with a tuned-pipe and a 9 mm carburettor, turns an APC 14x8 at 10,500, on just 5% nitro... This equates to 2.27 HP.

Your posted 8,400 RPM on the MA (K-series) 14x8, is just 1.26 HP and it is bettered by most muffler equipped .61 engines...


Believe me; the 'extra torque' you may be getting, equates to 'nothing flat', in an engine run at full throttle and at its maximum attainable RPM...

Your engine; unless it is transitioning to full power, is NEVER run at partial speed, with a fully open throttle; so any theoretical additional torque never manifests itself.


The pipe and 5% nitro cannot be not worth an 80% power gain...


Either the muffler is killing your engine, or it just has very low power...

I stand corrected on the Techniplate vs lubriplate, thank you very much. I did not profess to be getting maximum performance from my engine fuel combination, and I stated what the magazine reviewer said about the muffler used with the engine I have. Have you read the article and do you take issue with his inputs? I am satisfied with what I am getting with the fuel/oil I am using, as I am sure you are with your MVVS engines, nitro and tuned pipe. We are talking apples and cumquats here. I do not care to use a MVVS, nitro, or a tuned pipe, and am obviously not concerned with "B***s out high performance. I am sure most everyone by now knows how high performing your MVVS engines are, please don't bother telling me again. Thank you very much.

Sincerely,

SPACEWORM

Quote:

ORIGINAL: spaceworm

...I did not profess to be getting maximum performance from my engine fuel combination, and I stated what the magazine reviewer said about the muffler used with the engine I have. Have you read the article and do you take issue with his inputs? I am satisfied with what I am getting with the fuel/oil I am using, as I am sure you are with your MVVS engines, nitro and tuned pipe. We are talking apples and kumquats here. I do not care to use an MVVS, nitro, or a tuned pipe, and am obviously not concerned with ''B***s out high performance. I am sure most everyone by now knows how high performing your MVVS engines are, please don't bother telling me again. Thank you very much.

SW,


I resent what you are suggesting... as well as the language you're using to do it.

I was neither 'showing-off' the performance of MVVS engines, nor was I offering such an engine to you (none at all to sell).


I was just demonstrating how substandard your setup is; compared with a properly running engine of the same displacement.
I could have put an OS.91FX there; of which your engine is a China made clone, to show similar results, but I have no RPM readings on record for this engine.


And as to you not giving performance much importance; you're wrong!

To achieve its best economy, reliability and longevity, any engine must be set-up and run in a state that would maximize its performance potential, in any state that it is in.


Your Evolution engine is currently making 'sewer grade' performance, even if your FAI fuel and 'standard' exhaust are put into the equation.

Perhaps it is just the 'chokey' muffler that's on it...

"Your Evolution engine is currently making 'sewer grade' performance, even if your FAI fuel and 'standard' exhaust are put into the equation."


I was not talking about an Evolution engine. Maybe you did not read my posting as it appears you did not read the article on the ASP engine I WAS talking about.

Quote:

ORIGINAL: spaceworm

''Your Evolution engine is currently making 'sewer grade' performance, even if your FAI fuel and 'standard' exhaust are put into the equation.''


I was not talking about an Evolution engine. Maybe you did not read my posting as it appears you did not read the article on the ASP engine I WAS talking about.

OOPS!


I meant to write 'your ASP .91 engine...'.

The ASP is the exact clone of the OS.91FX; not the Evolution... I just carried over the in the name of the thread by error.


Sorry.

This statement is nothing more than conjecture. You have NO WAY of knowing what materials the factory in China verses the factory in Japan are using to manufacture the parts in these engines.

To make a blanket statement that two engines manufactured by two entirely different companies is an exact clone is just irresponsible in my opinion.

ASP .91
Specifications
- Displacement: 0.910 cubic inches
- Bore: 1.075 (in.)
- Stroke In: 1.004 (in.)
- Low RPM: 2200
- High RPM: 12000
- 2.200 bhp @ 15000
Weight (no muffler): 28.80 oz.


Os FX .91
Specifications
-Displacement: 0.912 cu in (15.0 cc)
-Bore: 1.091 in (27.7 mm)
-Stroke: 0.976 in (24.8 mm)
-Practical rpm: 2,000-16,000
-Output: 2.8 hp @ 15,000 rpm
-Weight: 19.3 oz (550 g)

Only when they are tuned too lean/overcompressed.


Ed Cregger

BW,


You are right and I was wrong...

The ASP .91 Series III, is cloned after the OS.91FSR, but with a 'square' head, resembling that of current/late FX engines.


This does not change the fact that Sanye engines in general are copied from OS engines.
I was just incorrect regarding the model.