T28RON

My Feedback: (32)

It has been over a year ago that I posted a Q regarding my World models CAP 232, weight is 13.5 lbs (I beieve is 1/4 scale-73-1/4 WS) however I did finish the cowl. It turned out great but did not get the yellow matched. Oh well, another time for that. I have had a lot going on in my life however am ready to fly the plane. I have a saito 4 stroke 180 in it because I was told that the plane will not perform with the 150 4 stroke. Here is my question: What is the recommended fuel for it and the prop size? I am new at 3D and the Saiti engines. I here and see so much controversy about fuels that I don't know what is best. however believe I am ready for the challenge. Any help would be deeply appreciated.
Thanks. Ron

gjeffers

first off the fuel of choice by many is 15% with at least 17% oil with some castor in it(saves your cam and reduces rust on your bearings)
i use omega 15% when i can get it it has 17% total oil and 30% of that is castor.

it also runs good on other fuels such as powermaster 15%and is my second choice.

ill let someone else answer the 3D prop question since mine runs a 16x8 ma 3 blade(not a 3D prop)
i would guess something like a 17x4 or something close to it

T28RON

My Feedback: (32)

Gary: thank you for the quick responce and info. The manual recommends 15% nitro and 20% oil. They also mention Omega fuel so I guess both will work. I have some 15% with 16% oil and I could add about 4 oz of caster to it. I think you are right about the prop size. I do have a 17" so I will try it first. There are a few folks on site that have flown the same plane with the O.S. 160 with great success however do not talk about fuels or prop size. I have been all over this site looking for someone that flys the same plane with a saito 180 and you are the first. Your Information and quick responce are appreciated. Thanks again.
Ron

gjeffers

Ron, be ready for this engine to be a gas hog while break in and untill you get low speed needle leaned down.
there is a club here and you are invited to join called club saito and you can get endless info there by some guys that have a lot more experience than me(that is where i get my help also)

click on the link below and chime in and you will be added as a club member by mr Robison!!

http://www.rcuniverse.com/forum/m_33...tm.htm#4300127

William Robison

My Feedback: (3)

Ron:

I'll just stick my nose in here long enough to say that your Saito will pull a six inch pitch for 3D, and with the higher pitch you wont be as likely to over speed the engine. Still at 18" diameter - the 18x4 might not be enough prop anyway.

And I'll echo Gary's invitation to "Club Saito," and second his recommendation of Omega 15% fuel.

You are right also with the addition of 4 ounces castor per gallon of all synthetic.

Bill.

T28RON

My Feedback: (32)

The engine has already been broken in. Thanks for the info. I will join.
Ron

T28RON

My Feedback: (32)

Bill: What can I expect for rpm minimum with your recommeded Prop 18 X 6. I can't find any info on how to caclulate that. Is there a formula for figuring rpm. Thanks

Ron

William Robison

My Feedback: (3)

Ron:

When the engine has a couple hours on it you should be able to idle at 2200 rpm easily, maybe as low as 2000 rpm. Depends on what prop you choose - how heavy it is.

While the engine is near new be happy with 2500 rpm.

Bill.

T28RON

My Feedback: (32)

Bill: Thanks for the reply however that is not what I wanted but is my fault. I wanted to know what the minimum full throttle should be with the 18 X 6 prop and is there a fomula that you are aware of.

Ron

William Robison

My Feedback: (3)

Ron:

Are you then asking what the peak rpm should be?

The FA-180 should run 9300 or so with 15% and th 18x6 prop, could be higher, up to 9700-9800 with higher nitro and/or more time on the engine.

Saito says the FA-180 is OK to 11K rpm, but that seems high to me for long engine life.

Bill.

T28RON

My Feedback: (32)

Thank you for that Bill: I had the same opinion. I agree that the lower rpm will give the engine longer life and still be able to perform as expected. I just needed to know what to expect with this prop size. I havent flown it yet. Am waiting for the auto glow and the snider pump. Will keep you posted.

Ron

T28RON

My Feedback: (32)

Bill: I lust installed a Electro Dynamics glow starter rather then make my own in the CAP 232. Works great. $39.00. I peaked out at 8220 RPMs. will fly it this week and let you know. As I was starting the engine I had a 25lb wealt to hold it dowm from moving forward and it started to pull it across the pavement. Had to lay my tool box across the line to keep the plane from moving and that was only at 1/2 throttle.
Ron