rbort

My Feedback: (4)

Hi guys:

Any of you own an FPE 2.4? And if so what rpms do you get with a 20x10 prop? I have the BME 44 and it spins a Mejlick 20x10 at 7200 rpms. Some guy at the field asked me about this, and then went on to say that his FPE 2.4 spins a 20x10 at 8800 rpms or something like that. Is that possible being a smaller engine than the BME? Am I missing something here?

-=>Raja.

TLH101

My Feedback: (90)

I believe mine was turning a Zinger Pro about 64-6600 when new. I've been using a 19x11n Mezjlick 3 blade lately, so have'nt tried a 20x10 w/ broken in motor. Turns the Mezjlik about 6400rpm.

CHM

My Feedback: (28)

I think he meant 6800? If it turns it 8800 I'll give him $600 for it.

My Brison 2.4 turned an 18x10 MenzS at about 7400.

Vince

My Feedback: (1)

I'll give him $650 for it. My Fox 2.4 spins a Zinger Pro 20X8 about 7200-7400.

Vince

jjmiller1

Mine turns 6600 with a Pro Zinger 20x10. My friends has about 5 gallons through it and it turns 6900. They're pretty smooth and easier to start with CH ignition.

Three

My Feedback: (2)

In this neck of the woods I'm getting 6400 w/20x10 pro zing, 7200 w/18x10 pro zing all with the CH upgrade. I was getting 6100 w/20x10 pro zing with the stock ignition. I'm waiting on a 20x8 pro. Been told I'll get 500 more.

rbort

My Feedback: (4)

Wow, lots of offers for his engine! I will ask him again next time I see him, or, better still get my tach to see if I remember to bring it! That sounded like alot to me too, so something is certainly not right.

-=>Raja.

lynngordon

Raja,

My FPE 2.4 with Syncro Spark upgrade with ported intake and venturi bleed hole fixed and run into the fuse will turn a 20x10 Zinger Pro or Top Flight wooden prop at 7130 on the ground, but I richen it up to 6930 to fly. The guy at your field is definitely off on the rpm. My other 2.4 engines, a Brison and a Fox, turn the same props at 7000 and 7400 rpm respectively. This is using a 40:1 fuel oil mix using non synthetic low ash oil (for break-in). I will use Amsoil 100:1 when the break-in is completed, and expect to pick up 100-200 rpm on each engine at that time.

Lynn

flyindoc

My Feedback: (8)

You must have gotten lucky with your 2.4. I've got a Brison 3.2 that turns a MenzS 20X10 at 7400. I live in WV and fly at about 2000 ft above sea level. The engine has been tuned to perfection. Has about 4 gallons thru it and a degree wheel was placed on it to ensure the timing was right. 7400 on a 2.4 is a lot of rpm with a 20X10.

Just my opinion.

Andy

sirmombo

I am getting 7100 with a master airscrew 20 X 10. That's at sea level. I had Kurt at FPE weld one of the muffler exits closed. It's a little quieter and Kurt thinks that may be helping the engine a little. He said it was turning around 500 rpm higher than most of his 2.4s. I am using the stock ignition.

rbort

My Feedback: (4)

Don't mean to throw the numbers off, but, are you guys checking the RPMS with the tach when the engine is cold or hot?

By this I mean if I go to the field, fire up my BME 44 and tach it right away, I get 7400 rpms on the ground. Once it heats up, it loosens up and the compression probably drops, as I get 7200 rpms then (sustained rpms).

So, I tend to tach my engine AFTER I land but before I shut off the engine. That way I know its at operating temperature, and whatever I get there is the right number. In my case its 7200 with the Mejlick 20x10.

To the guys who are getting 7400, are you taching cold or hot? Also prop makes a difference, for example the master airscrew prop unpitches when you throttle up and spins faster -- you can see that if you look at it from the side while running.

-=>Raja.

sirmombo

It doesn;t make sence to me to tune or tach a cold engine. The engine is warmed up or hot nearly all the time it's running, so why worry about the minute or so that;s it's running and cold?

I think this thread could easily degenerate into a FPE vs Brison vs BME vs Fox vs ZDZ... thread. If somebody says they get X rpms and someone else says they Y rpms where X > Y, that doesn't necessarily the first person has a stronger engine. There are just too many variables. I personally think all the 40cc engines are very close in power and customer service should play a bigger role than someone saying their brand X engine turns a prop 200 rpm faster than a brand Y engine.

STUKA BARRY

I AGREE WITH YOU SIRMOMBO. AS I ALONG WITH VINCE AM GETTING 7200 ON A MEZJLIK 20X8 ON MY NEW FOX. ITS GETTING SOME FLIGHTS ON IT NOW SO I'D SAY WITH IT STILL BEIBG RICH, MAYBE EVEN 7300 0R 7400 RPM. I LOVE THAT LITTE FOX. IT STARTS RIGHT UP AND NEVER QUITS. I'D PUT IT UP AGAINST BRISON AND 3W.

skymat

Have the FPE 2.4 with the ign upgrade and std zinger 20x10 and i'm getting about 6550 rpm. Going to the Biela 20x8 and should get a good boost and will also try to plug one of the stacks......any reccomendations on which stack to plug or does it matter?

qspilot

Taching a hot engine makes sense but this engine is air cooled in flight. On the ground the are not. Don't know how much difference it makes.

Chris

lynngordon

All rpm's reported in my above post are accurate for the FPE, Brison and Fox 2.4s as measured on my HobbyCo Digital Mini tach while the engines were warm. They each have about 8 gallons through them, and are about ready to switch over to the synthetic oil/fuel mix.

I have modified my engines to include a 1 1/2" velocity stack on the intake and soldered a tube over the diaphram relief hole with a tube then run to the inside of the fuselage so the prop blast doesn't change the pumping/mixture. The velocity stack adds another 100 rpm to the top end of each of the engines.

I plugged the front exhaust stack on the FPE for a 200 rpm gain, and went with a CH Syncro Spark and 28 degree total advance hub from Kurt. All the changes to the FPE resulted in a performance increase from about 6600 max to 7200 on a cool day at sea level on the 20x10 wooden props.

The Brison has no mods to it other than the velocity stack - still has the manual advance.

The Fox has a velocity stack and CH Syncro Spark, and was the most powerful of the engines right out of the box.

Have not yet experimented with different brand mufflers to see if I get a gain in rpm, but with just the few mods made, I am extremely happy with all three of these engines and would recommend any of them to another flyer. All have a good idle, an acceptable transition, and a good top end. When propped to run anywhere between 6800-7200 rpm, they generate enough thrust to accelerate vertically any of my planes which are all between 14lb, 6oz to 15lb, 9oz.

Lynn

Jimmy Bananas

My Feedback: (13)

I have an FPE 2.4 and am swinging a 3-W 20-8 prop..Haven't tack it yet,but will today...got one in a Kangke Laser 2000,and one in a Texas Hurricane..Hurricane gets it's test flight today...Laser 2000 weights 16 Ibs,and the hurry weights around 13 Ibs...FPE handles the Laser very good..with a 3 Ibs less on the hurry,should be a ball to fly..Just my 2 cents worth

STUKA BARRY

MY LITTLE FOX 2.4 IS BOLTED ON A VAILLANCOURT STINSON L-5. THIS PLANE IS BUILT LIKE A TANK. IT ORIGINALY HAD A G-62 ON IT. I FLEW IT BUT IT WAS VERY HEAVY ON THE STICKS AND IT LANDED LIKE A HEAVY METAL WARBIRD. AFTER PUTING THE LITTLE FOX ON IT. THE PLANE IS EASIER TO FLY. THE L-5 WEIGHS 25LBS. AND THAT LITTL FOX PULLES IT AROUND VERY SCALE. CANT SAY ENOUGH ABOUT THE FOX 2.4 FORGOT TO MENTION, IT HAS A BOLD MUFFLER ON IT. A PLEASING MELLOW SOUND AND STILL TURNS 7200 RPM. THESE PITTS STYLE MUFFLERS ARE GREAT.