Tigre Food

I have ST46, 51 (old and new type) and 60 and see conflicting information on the best type of fuel to use. 20% castor seems favourite but should I use part synthetic to keep the rings free? What level of nitro would be best 5%, 10%?
Thanks guys.

LAST EDITED ON May-20-04 AT 12:13 PM (CDT)
 
I have used 20 to 22 percent oil in both all castor and castor/synthetic blend in these engines. Being ball bearing with ringed pistons they don't need a ton of cooling help like a Fox or McCoy so all castor is an option, but not a necessity.

The main reason I use the blend now is less mess on the airplane, plugs are running a bit cleaner, and less fuel consumption, which with a 60 and a marginal tank size can be a very worthy reason.

I run 10 percent nitro usually, but I live at sea level. If you need more, use it. The guys at high elevations run a lot more than you think. At Tucson (2500 feet MSL) some guys normally fly with 20 percent in ST 60's and more in ST 46's.

Generally if you have a need for a 4-2-4 break, less nitro will produce that type of characteristic, if you need more power or less break then more nitro will be a help.

Either type oil blend should be proper for these engines. Any nitro content to provide the type of run and power will be correct. Good luck, I always have been a fan of Super Tigres.

What Chris said.
The Layster recommends all castor in his engines and he fits the ring so that you will not have a sticking problem. I have run both.
In my T&L G51 the all castor gave a more consistent run. Didn't seem to matter on the stock 46s though. HAven't run my 60s that much
Bill <><

LAST EDITED ON May-22-04 AT 03:48 PM (CDT)
 
All good advice above. I use 22% oil in my ST 46 AT 50%/50% synthetic and caster. I have used more synthetic like 80%/20% and didn't seem to make a difference. Tom Lay recommended 22% all caster for the ST 46 I got from him and that worked good also. So I think you can use what works best for you and whats available in your neighborhood if you stick around the 22% Plus or minus 2% oil. Now nitro is a different story. Not that it's a problem. It's just that the bigger motors seem to work just fine on 5% and 10%. On the ST 46 I have used anywhere from 5% to 20% depending on the conditions and the plane and all worked great as the ST 46 responds well to nitro and still gives a good stunt run. On hot days when I use the higher nitros you will use another ounce or so more fuel for your pattern, so you will have to practice and adjust for it ahead of time. For a little more power if needed Brett Buck recommends a .173 venturi. I am using this, following his advice and it works great even with the stock venturi. I don't have experience with the ST 51 or 60 but there are others here who do.

And what size / type prop would you use? Where is a good place to start with the 46 engine?

LAST EDITED ON May-21-04 AT 11:49 PM (CDT)
 
I am running a Brian Eather 10 3/4 x 5 3/4 undercamber cut down from a 11 3/8 x 5 3/4. The Brian Eather 11 x 5 3/4 U/C has worked well for me also. Got this one from Tom Lay. Any of the 11 x 5, 11 x 6 or 11 1/2 x 5 or 6, 12 x 6 woods or Rev-Up type are a good start also. I tried the popular APC props and was not happy with them. On my profile which is a little on the heavy side I have been using the Brian Eather and it has improved tension over all the other props that I have tried. So I have been using this prop for the last year and a half. On a plane of my size 56 in wing span & weight the Brian Eather would not work without the enlarged venturi to help with the power. Uniflow clunk tank with pressure or without. But once you get it set up, it is sweet! GRINS