planebasher

I presently have two Zenoah M-5 engines.

I know what this modification consist of; can anyone tell me what the additional mods are to get to the M-6 level.

Thanks,

pyro1

Go to WHHs site and the differences are listed for each mod. Or give Tony a call.

magnum57

Our performance proven M5 engine modification is becoming the popular choice for both Enforcer boat owner upgrades and also DIY customers. The M5 boosts the Zenoah G260 engine over 1HP and can provide a usable RPM range of 15,000 RPMs with the use of a tuned pipe. This performance boost can provide speeds in the mid to high 40s, yet maintains its reliability. The M5 can use both a Wet or standard Dry Tuned pipe, and works well with the WT644 (Big Bore) carb that comes with the Zenoah G260 engines. This is the perfect modification for engines with a clutch, offering both high speed performance, low end torque, and good idling characteristics.
Increased Compression
Relieved Piston
Raised Exhaust Timing
Copper Coated Base Gasket


The M6 engine modification is quickly becoming the engine of choice for competition model boat racing. Higly modified, providing sustained RPMs over 17,000 @ over 4HP. This engine is perfect for competition model boating powering Vee bottoms, Catamarands, Hydros, and Outriggers. The M6 is designed to be used clutchless and requires our Dry Tuned pipe system with 2 inch powerband for proper operation.
High Compression
Relieved Piston
Lightened Piston to 21 grams
Lowered Intake Timing
Raised Exhaust Timing
High Hat Exhaust Porting
Copper Coated Base Gasket

Note: Requires WT257 or CA5003 Big Bore Performance Carburetor.

planebasher

Thanks for the info.

I would like to see an example of "High Hat Exhaust Porting" if anyone knows where I might find such.

I would think that raising the compression; which as I understand it; would require lowering the cylinder either thru milling the base or decreasing the gasket thickness; would in effect lower the intake timing, I noticed that on the m5 cyl I have; the size of the transfer ports were not altered in any way; the only modification was to the cyl height and the size of the exhaust port, and the piston was relieved.

I have a cyl that I have enlarged the transfer ports, and eyebrowed them into the intake area and modified the skirt of the piston as shown on MGB; and reassembled without a base gasket; but I did not alter the port timing. The engine runs and idles excellent; but until I can get some performance data I won't really know if I have accomplished anything.

I am trying to get additional torque to turn a larger prop since this engine is in a Magnum 57 hull, and my best performance to date has been with the larger diam props. just need to turn them a little faster.

Thanks,

benckie

it souns like the stock rcmk evo heads produce more rpm and hp then the m6 mod head

Nosedragger

yep, does doesn't it

benckie

and cheaper, you might want to looking intom modding them instead of trying to milk more out of the m5

MACGYVER1

go with the BH Hanson hornet.or a C.C. motor.Go on jimsboatdock and ask around.

illiniboater

My Feedback: (1)

I think the whobbies motors hp ratings are pretty conservative. I've never ran a M6 but do have an M5 that I lent to a buddy this pat summer. It was pushing his Avenger to 57mph and I believe there was a couple mph left in it somewhere.