Lanier F-4 Phanton 40 ARF--that would move along pretty good with a 61FX.

GP Shoestring Racer 60
GP Little Toni Racer 60
TH Kaos 40
Lanier Predator--ROCKET SHIP!! with a 61FX on it.
Lanier Invader
Thunder Tiger Rare Bear

Kit:
GP Patriot-fast-fast-fast
Lanier Shrike 40--LOOK OUT!!! with a 61FX on it.
Balsa USA Enforcer
Balsa USA Force One
Balsa USA Northstar

I've had 3 of the 61FX engines over the years. They are a good sport engine. Great for general flying and there's not a thing wrong with them. There are a few other engines in the same class that may have a few more ounces of power--but I wouldn't laugh at a 61FX. They are fine engines.

They respond REALLY well to a tuned pipe. The full tuned setup is kinda spendy--but you WILL notice a big difference. You can get cheap power by simply bolting on a Macs muffler #6860. It's about $38 and will give you a few hundred more RPM.


I did drill out the crankshaft on one of mine. I did this on the engine that I had the tuned pipe on. I can't remember exactly how much I drilled it out. It wasn't a lot. Just one drill bit size bigger than the factory hole. Deburr it and clean up the intake opening with a little sanding stone on a dremel. Make it SHINY inside. That helps fuel flow.

Get a degree wheel and determine your intake duration. Grind on the CLOSING side of the intake hole in the crank and increase yoyr duration a bit. NEVER--NEVER grind on the OPENING side of the crank. You'll mess it up and the engine won't run for sh*t after that. A little goes a long way--so don't grind off more than maybe 1/16th of an inch.

If your daring- you can grind off the sleeve on the exhaust side. The exhaust port is always bigger than the opening in the sleeve. Grind away the TOP of the sleeve untill its even with the case. DON'T grind away the center vertical support in the sleeve where the exhaust opening is. Can't remember off-hand if it has that vertical support or not. Some engines do--some don't If it does--leave it alone and just grind away on the top of the sleeve untill you are flush with the case opening.

One of the carbs for the heli engines will bolt right in. It has a 3-needle setup. You can adjust the midrange. With the full tuned pipe--and a 3-needle carb--you can really get it dialed-in for great performance at any throttle setting. THAT will make it a real screamer.

They responod very well to minor mods. But don't get all crazy. Your limited by the transfer port timing--and you can't change that. You can get a better carb. from a heli. You can drill out the crank a bit for more flow. You can grind off the CLOSING side of the intake post on the crank to increase intake duration. You can grind away on the top of the sleeve at the exhaust port to increase exhaust duration.

Easiest thing to do it bolt up a Macs muffler.

Tuned pipe is great, but lots of $$$. If your gona spend the $$ on a tuned pipe--then make it worth the investment and buy the heli carb. and do some grinding on various areas of the engine.

You will be TOTALLY amazed at what a 61FX with a few mods and a pipe will do.

But still, nothing wrong with a stock 61FX. Put the Macs muffler on it and have a blast.