DanPeoples

The other day I was hunting for a speed engine on ebay to go into my new magnum r arf when I came across an engine I've never heard of before called a BH 52A. These engines are being sold by Bonparhobby, I've heard the name mentioned in a couple of past threads but have not come across any posts that talk about these particular engines. From what I have gathered these engines are made in the same factory as the magnum line of engines and the parts are fully interchangeable.

Out of curiosity I placed a bid on one and have since made it my goal to modify a cheap 46-52 size engine ($50-$75) and either increase its performance by using a tuned pipe ($100 or use old one) or have the new engine sent to someone to get ported, polished and balanced ($100).
Heck I'll probably add both the pipe and get the engine work done, but the end result that I'm looking for would be an engine that would run happily above 18,000 rpm and have decent power for a fast model yet look like a sleeper.

Before everyone says just go buy a Jett .50 and be done with it, I would like to add that I fly a Jett .50 and my first magnum came with the V1 engine combo which flew great so I'm well aware that great speed engines already exist. My goal here as strange as it may be is to take a cheapo sport .52 engine and give it a little extra edge to make it turn higher revs happily. This is purely for fun and might be an indication that I have more spare cash then brains at the moment, but just humor me please.

My questions to those of you that have experience modifying engines is:
-What kind of power increase could I expect from the engine work and pipe combo?
-What information should I provide the engine tuner as far as exhaust timing and etcetera?
-What should be my target rpm and prop for this airframe, should I just stick with an 8x8 or just trial and error a few?

Thanks in advance,
Dan

daven

My Feedback: (1)

Just go buy another Jett

I'm just kidding, have fun.

MyWay

Or buy 5 Gms .47 engines and use the exhaust timing and carb size on your Jett 50 for reference. 9x8 =18000 +with tuned pipe.

DanPeoples

The closest carb that I have is off a ofna .21 buggy engine. It looks really close in size but the throttle cable would have to be at a 45 degree angle due to the slide carb configuration. I wonder if the stock .52 carb would be adequate with some light modifications.

evan-RCU

You can drill out the carb to get more airflow but at some point the volume through the crank will be the problem. Port polish and balance is old car terms, the model engines can have port work as in matching ports to pipes and raising and lowering the ports and they can be balanced sort of but polishing refered to the intake and exhaust runners in the car heads and doesn't apply much to model engines. I think doing this will give you some great education, let us know how you make out!!

DanPeoples

Here are a few shops that I've come across that can perform the engine work:

http://www.rbmods.net/
http://www.tntmods.com/

rmenke

My Feedback: (13)

Dann P:
The engine that has come close to running down my Jett engines is of all things a K & B screemer 48. Stock it was not much. Now it has a performance specialities tuned muffler on it and I suspect some heavy modifictions. The rpm its turning sounds higher than my Jetts. His plane is modified av-star of all things. The combo is not far behind me in the races. He is a old racer, would not be supprised if Clarance Lee himself modified it for him. Anyway, this motor in current form does in fact scream. In like planes, I don't think I could keep up. May be worth looking into! Bro #119

DanPeoples

From what I've heard Clarence Lee is bad to the bone when it comes to model engines. That .48 must have gone under the knife in order to run with your jett, that muffler couldn't be the only mod.