OS Max "S" 30, 35, 40

[Motorman]

Are the motor mount holes the same on the 30, 35, 40 os max S?


Thanks,
MM

[RandySmith]

Are the motor mount holes the same on the 30, 35, 40 os max S?


Thanks,
MM

they are the same on the  30 and 35 S

Randy

[Gerald Arana]

they are the same on the  30 and 35 S

Randy

B-40 fits these mounting holes too.

Jerry

[Clint Ormosen]

B-40 fits these mounting holes too.

Jerry

Yeah, and not just "pretty close" either. Exact fit.

[frank mccune]

     Hello Walter:

     At present I have planes that have all tree of the above mentioned engines installed.  Yes, the mounting holes are all the same.

     I swapped a .40 for a .35 and noticed very little gain in performance.  Of course the .40 is larger and a bit heavier.  The .40 provides a great stunt run!  The .30 and .40 are the best kept secrets in the Stunt World!

                                                                                                                  Frank McCune

[Motorman]

Thanks guys. I have an S30 but have a chance to get a nib S35. If I can get it I will give the S30 to a buddy who wore out his S40 so, it's good they all fit the same foot print.

MM

[richardhfcl]

What is the OS Max "S" 40?  I recall the "S" 30's and 35's.  When they went out of production we had

F.P. 35's and 40's; but I don't recall "S" 40's.  Is that the same as the OS Max 40 H's?  Thank you for

the information.

     Richard Ferrell

[Dan McEntee]

   There  was no MAX-S.40. You are correct on the 'H" designation. It is used for stunt, but I don't know if it shares the same mounts.
  Type at you later,
    Dan MvEntee

[Air Ministry .]

WELL ;

I checked Last Night , And the OS H 35 C is the same as the 35S , which is the same as a 30 . As the 35C is the Same as a H-40S ,
the 40S is the same as the 30 & 35S . 

The Laters FSR-S ( and non-S ) arnt, whoever , theyre allmost nearly but not quite the same as a ST G-51 . Close Enough to swap .

I wasnt going to pull the 40S outta the MC-72 just to measure the holes .Seems to need a 11 x 5 in that particular aeroplane . More the PLANE does .
In the Mags back in ' the day ' people said the H40-S was the equivilant of a ST 46 , and maybe stronger in the 4 - stroke than the 46 .
Bob Hunts F-`105 Thunderchief ran a 40 S . I think it mayve met its end in a flyaway over tarmac . Something like that , anyway .

[Randy Cuberly]

   There  was no MAX-S.40. You are correct on the 'H" designation. It is used for stunt, but I don't know if it shares the same mounts.
  Type at you later,
    Dan MvEntee

Memory tells me that the mounting holes for the S35 and the 40H are the same but I believe I had to file out the mounts on a Nobler when I installed the 40 in place of the 35.  The crankcase is a bit wider and "longer than on the 35S.

Randy Cuberly

[frank mccune]

     Hi Randy et al:

     Randy you are correct! The O.S .40 S ,Stunt, does indeed require that the engine mounts be made a bit wider.  The entire engine is a bit larger.
 
      There was indeed an O.S. .40 Stunt engine made and sold.  It can be identified by the letter "S" cast on the case below the .40 marking.  It also has a single ball bearing in the rear and a plain baring in the front. It has a single standard ring  I will research some old engine tests to determine how much horsepower they produced.  I think that it was about .62 horsepower. 

      I have one in a Nobler and it is a joy to use! It starts very easily and runs in a very steady 4-2-4 mode with an 11x5 or an 11-6 prop.

      I know that it is "old and obsolete but it really works well for me.  I have many "old" engines that perform vey well. LOL

                                                                                                                     The best to all,

                                                                                                                      Frank McCune

[frank mccune]

   Gdaymate or is it Hello Matt?

    As always it is good to read your posts.

    I did a bit of research comparing the OS .40S to the ST .46RC.  The OS .40 produced .62 hp and the ST .46RC produced .84 hp. That makes the ST 15% more powerful.  The weights are about equal.  The ST is 14% larger in displacement.  Both are ringed engines with baffled pistons. Not surprising that both engines turn out about the same hp. per cubic inch of displacement.  Perhaps the ST with the laminar flow and extra ball bearing made up the extra 1% in hp.  I wonder how much the RC carb affected the ST engine for total hp. as compared to the venturi used in the OS .40S.

    I guess that the nod would go to the ST for stunt use. Both are fine Stunt engines from the Past.

                                                                                                              Be well my friend,

                                                                                                              Frank

[Mark Scarborough]

   Gdaymate or is it Hello Matt?

    As always it is good to read your posts.

    I did a bit of research comparing the OS .40S to the ST .46RC.  The OS .40 produced .62 hp and the ST .46RC produced .84 hp. That makes the ST 15% more powerful.  The weights are about equal.  The ST is 14% larger in displacement.  Both are ringed engines with baffled pistons. Not surprising that both engines turn out about the same hp. per cubic inch of displacement.  Perhaps the ST with the laminar flow and extra ball bearing made up the extra 1% in hp.  I wonder how much the RC carb affected the ST engine for total hp. as compared to the venturi used in the OS .40S.

    I guess that the nod would go to the ST for stunt use. Both are fine Stunt engines from the Past.

                                                                                                              Be well my friend,

                                                                                                              Frank

Please remember that Horse Power is typically a peak measurment, derived as a function of torque and rpm. As such its pretty much useless as a reference for stunt. a higher rpm motor with less torque will potentially appear to be more powerfull but when you address the rpm range we live in, you might find the torque is not there.
its about torque AT the rpm we need that matters as well as other qualities not related to horse power directly that define a stunt motor