Can somebody name this engine on the original RCM Sun Ray biplane from 1975?

I'm guessing it's a Super Tigre but I'm not sure. Sorry I don't have a better picture.

Very hard to tell but it looks like an American engine to me: Fox, K&B. Or it could be a Japanese Enya.

David.

The muffler appears to be smooth with no cooling fins and the carburetor housing looks cast aluminum. I don't think it's a Fox or K&B. It doesn't look like an Enya carburetor either.

For sure not a Tigre, I was thinking Enya or maybe Veco. The carb is alost Enya like, I've got a .40in the garage and it's close.
hook

Looks a little like an HP. Really hard to tell with that pic.

It could be a HB or a HP engine ...Perhaps it is a Webra Speed thats my best guess the early mid 1970's models had a very Square carb and I have muffler with no fins.

What size is the Engine ?

Johnkpap

The Sun Ray specification sheet says .61 cubic inch.

If you look very carefully at the muffler you can see the cooling fins along the top of the straight section. It all looks like an OS item.
Evan, WB #12.

Hi,

I'm almost sure it s a HP 61 F-RC with its orginal muffler. See image below of such engine from 1973.
They was made in end of 1960th and beginning 1970th.
I know a guy in my RC club in 1970th that had such engine, he used it ina Midwest Mach 1, it was 1974-1975.
Good power but rather high soundlevel, nice blue cylinder.
Muffler shape, top (4 screws) and carburator throat looks same on your picture and the picture I posted here.

/Bo

Bo is correct. The original Sun Ray came 2nd in the October 1974 RCM "Model of the Month" contest and these are the details of the model.

Ray

Good one Bo,

right on the money!

David.

What appears to be cooling fins is a reflection off the smooth surface. At first I thought it was fins too.


Thanks for all the replies and give Bo and Ray a big round of applause for confirming the Sun Ray was equipped with an HP 61 engine!

Mike

Mike,

Might be worth a quick trip to 2307 Windsor Road

Ray

You noticed we both live in Austin! I actually tried to contact Jack Scarbrough many years ago but he no longer lived on Windsor Road. I wanted to ask about obtaining plans for his Delta Pusher, another unique design. I'd still like to find those plans.

Jack Scarbrough's Delta Pusher was briefly described in the April 1978 RCM Sunday Flyer column. This column has the only picture and info that I've been able to find on this model. It's so cool!