chevy43

I just bought an OPS .60 but I know nothing about it exept it is ball bearing. I''m wondering if this is a hi speed or hi torqe engine? Small or larger prop?

It came with a hand made diesel head and the red colored glow head.

I ran it on diesel and got thease #'s so far.

14x6 MAS 2000 - 7500. This prop seemed to be too big.

13x6 Zinger 2500 - 9000. Better.

12x6 APC 2,700 - 11,000. pretty good.

I didn't have time to try an 11x6 yet....

It also has a big Super Tiger mufler on it and the hole is kind of small on the back.. I should have tried it with just the header pipe but didn't have time...

MJD

My Feedback: (1)

Well, I''d say 11k on a 12-6 isn''t much to write home about for a relatively high performance .60 even on diesel.

Is this a front intake, side exhaust engine? What is the vintage?

Harry Lagman

Chevy, judging by the numbers your engine is posting, the engine seems to be happier with the lighter loads. A good glow .60 with a normal muffler will do somewhere between about 11,300 and 12,000 with an APC 12 x 6, and you are approaching this still running in diesel mode, so I''d say that''s a pretty good effort.

Try the APC 11 x 6 (and an APC 11 x 7 if you can) out before you convert to glow and see if the even lighter load brings more benefit.

Once you convert to glow, run the same props and report back. This will be a really interesting study.

chevy43

It is a front rotory vavle and side exhaust. I don't know the vintage.. It has what looks like a Perry carb but it doesn''t have Perry written on it.....

I tried a 12x5 and 12x4 zingers but the results weren''t much better than the APC 12x6. Sometimes that happens with Zingers though. I would have used APC''s for the comparison but didn''t have them....

I tired a 11x5 MAS and it did 13k but acording to my thrust calculator that isn''t any better than the 11k on the 12x6.

So on diesel it looks like the 12x6 is best so far.

Broken Wings

My Feedback: (20)

If it has the red head side exhaust its an OPS Ursus, made around 1973. It''s a screamer.

chevy43

It has the red head. I just ran it on 10% glow fuel and got about the same RPM on the 12x6 APC. Maybe that is way too big of a prop for glow use?

Broken Wings

My Feedback: (20)

Try an old master airscrew 11x7,

Make Model Type Capacity Bore Stroke Weight Magazine Issue Reviewer
OPS 60 Ursus glow 9.829cc 23.85mm 22mm 18.4 MAN Apr-82 Chinn

Ursus is Latin for "bear".

I found this as well

(snip)
Hello, this redhead OPS 60 is a high quality ABC engine being designed for competition pattern flight and was offered between approximately 1975 to 1980. Sadly no spare parts available these days from OPS .

The liner features three ports. It is a short stroke engine that will best run with a 11x6 or 11x7 prop, tuned pipe and low nitro content of max 10%.

The correct indication for this FIRE engine is OPS .60 Ursus SPA RCA. The front intake, side exhaust version was named Ursus SLA.

The newer pattern versions come with a goldhead and feature 5 ports. These are called „Super“ instead of „ Ursus “.

As for the „SPEED“ variants, both redhead and goldhead versions are always rear intake/rear exhaust. (Snip)

I had one of these (Ursus SLA) and never did anything with it. I lived in New Orleans and Shamrock Competition Imports used to be the Dealer for OPS engines way back when.
I ended up swaping it for something or other....