jim52519

My Feedback: (3)

Hi All,
Is there a fuel additive that can be added to gas to increase the power of a G62? Is there any engine mods that are easy to do to increase power? I think it is possible to switch to alcohol fuel but I am wondering if it would then use twice the amount of fuel? Also what steps would be required to switch to Alcohol?
I am flying a 33 LB Stearman and would like a bit more power.

Jim

rcdude7

My Feedback: (264)

For a big kick in the rear, add a header and tuned pipe to that engine. If you go with glow fuel, you are certainly going to burn alot of it, and have the corosion problems that glow engines have.

mrbigg

My Feedback: (21)

Remove the 62, sell it, and put at least a 100 twin in there. If it was my plane, it would have a 160 in it. Your severly underpowered as far as biplanes go.

rcdude7

My Feedback: (264)

A 160 in a 33lb stearman? HMmm.......

It would be just a little overpowered.

freeair

the G-62 is just a piston port engine with magneto ignition, this engine type will never have the power of a simular sized engine that has rear induction via reeds and electronic ignition. not knocking the Zenoah engines atall as they are probably the best 2 stroke engine on the market, its just a shame the Komatsu Zenoah dont think and put out rear induction engines. so as far as gaining abit more power you should fit a pipe with a manifold that matches the exhaust opening without restrictions, run the engine on AV-GAS which is normal light aircraft aviation fuel that does have a higher octain level than any servo pump fuels, try some different props.

the Wasp

My Feedback: (1)

""the G-62 is just a piston port engine with magneto ignition, this engine type will never have the power of a simular sized engine that has rear induction via reeds and electronic ignition""

I wouldn't say never, that's for sure, opening-up the ports will do wonders !!


to start try a Bolly Carbon Prop, my friend picked up-about 800 more RPMs on his old Sachs 4.2 with a Bolly Carbon, yes it has to be a Bolly, they really rev-up..

Jim

freeair

Jim, it shows you dont know alot about the opperations of a 2 stroke engine. if even you know exactly how to open up the ports you still will not match the performance of a reed injected engine, this is truth not fact. think and inquire about this.

Texastbird

Are you running the stock muffler? They restrict the potential power quite a bit. There are some mufflers around which will help the top end quite a bit if you don't mind the extra noise. I have just started playing with my new G62 so I can't be specific, but I know some of the fellows running them have found quite a bit of extra power without going as extreme as using alky fuel. And I think if you did put a much larger engine on that beast, with all the drag it wouldn't go much faster

pe reivers

It is not so much more power you need, but more thrust to move that draggy plane.
Above 9000 rpm a piston ported engine with tuned intake duct and tuned pipe will outperform a reed engine. For the Stearman, a prop reduction allows the use of a large 32x18 prop that will give that plane a lot of gusto.
I do not think that the G62 needs to be ported for that. It's port lay-out already is designed for 9500 rpm.

mrbigg

My Feedback: (21)

Exacty Pe. Draggy bipeplanes take more power. I had a ZDZ 120 in my 29 pound Ultimate. Plenty of power. Actually just right. I just put a 160 on it. Have yet to fly it. The 160 in that Stearman would be perfect. Nice cruise at half throttle.

Tired Old Man

My Feedback: (1)

Using av gas will not provide even one iota more power than the 87 octane the engine was designed to run on. Why does anyone think a higher octane rating equates to more power in a low compression engine?

Jezmo

That's a good question T.O.M. cause the extra octane will help stop detonation but will not create any more pressure in the chamber. I sure do like the smell of it when it's running though.

Tired Old Man

My Feedback: (1)

Gets better with kerosene derivatives....

the Wasp

My Feedback: (1)

freeair,, for your info I was porting Zenoah 23cc (s) and Home Lite 25cc then 30cc back in the late 80s and early 90s for RC boats (that is why I bought my milling machine), I did a lot of engines for me and others, in fact I was moding their pistons back then when no one else was

Jim

CK1

My Feedback: (60)

Take a look at the Reeves Torque Master by Mick Reeves Models . I have no experience with it ,but it looks cool....

www.mickreevesmodels.co.uk/ - 20k - Similar pages

TORQUEMASTER £195. Export £170.
SPEED REDUCTION UNIT for ZENOAH 62
50% Thrust increase, from 20lbs for standard Z62 to around
30 lbs when fitted with Torquemaster.
1. Bolt-on Unit. no modification to the engine.
2. More torque drives bigger props for increased thrust.
3. Moves the thrust line closer to the centre of the engine.- Easier cowling.
4. Ratio 1.75:1
Thrust - 30 lbs. Weight - 2¾ lbs. Length increase - 2½ in.
Prop shaft is 75 mm above engine shaft. Pulley runs on two ballraces.
Prop .........RPM A well run in engine can give 10% higher RPM.
26 x 8 ......5400 (prop too small. Suggested max RPM - 5100 on prop.
26 x 10 ....5200 (a bit small)
28 x 12 ....4600
28 x 14 ....4400 (takes my 1/3 Camel up vertically!)
30 x 11 ....4000
32 x 12 ....2700 (too big for max power)

freeair

Jim , we have simular histories. i was also doing alot of work on the old Zenoah G-23 first model black housing then came the twin coil G-23, i did the work on Tony Grinters Outrigger engine which was powered by the black mod G-23 which gave him a World Record for straight line speed. i never thought much on the Homelite engine though.

jim52519

My Feedback: (3)

CK1,
The Torquemaster looks interesting but at this point I would have to redo the whole front end of my Stearman. If I knew what I know now I would have built the plane around another engine, possibly a DA85. But now I am going to stick with the G62. I switched to a Jtech muffler which added about 400 RPM's. There is no place to install a tuned Exhaust on the stearman without destroying the looks.
I was wondering if I am missing an easy way to increase the HP. would raising the exhaust timing buy me anything?

Jim

Lnewqban

To increase compression ratio and increase octane grade fuel (and may be reducing plug thermal grade, and also spark timing if needed)?

To retard the timing for using a bigger propeller at lower rpms?

To polish the intake ports?

To use an intake ram duct?

Just some humble suggestions. [sm=spinnyeyes.gif]

freeair

by raising the exhaust timing you will gain in rpms but torque will suffer. you can slighly widen the exhaust port and both match this area with the manifold and polish smooth, also check how the piston looks at BDC looking through the port, if its not flush with the port base you can machine down this base to suit . before you start any of this you must firstly measure [ head clearance ] squish band clearance with the good old solder test. if you feel there is room to remove a few thou , do so by either machining from the cylinder base / mill the top of case or the easy way , remove or replace the cylinder base gasket with a thinner copper gasket, this is instant power. the slanted sparkplug cylinder heads are not the best for modding compared to the vertical plug type that has a real dome and squish band but more compression does equal more power. you can also check your intake manifold to cylinder head to make sure the openings are identical without any slight restrictions such as a slightly smaller diameter manifold block to cylinder intake opening. there is alot you can do to this particular engine to gain heaps of power torque and still keep and gain rpm,s.

Bill Clark

higher octane + more timming advance= more power. Right TOM

actually switching to very high octane gas w/o doing anything else will reduce power

freeair

av gas is not what you would class as a high octane fuel but it is higher in these levels and is more purified than any servo pump fuels . this is why the AV [ AVIATION ] comes into things, most or nearly all light aircraft pilots prefere to use this fuel in there craft engines as due to greater refinery etc its alot safer than pump station fuel that sometimes you really dont know what your getting in the mix.

Kweasel

My Feedback: (29)

Easiest power increase for G62 at airplane RPM is removing the base gasket and using a better muffler.

Tired Old Man

My Feedback: (1)

From Kweasel, finally a valid method of easily improving performance a little.

The next most sensible is selling the 62 and obtaining a BME 58. Weighs less, effectively providing more power through aircraft weight reductions.... The next step is getting a larger engine (more weight) or using a Macs pipe for the exhaust on the 62. You could change from gas to alcohol with the 62 but by the time you had it set up for the most power you would have a finicky engine.

BTW, full scale pilots use avgas because it is generally pure after refining, graded to higher standards, stored better, does not contain ethanol to degrade fuel system plumbing and carb floats, and is dyed to provide verification of type. Unless an STC has been obtained, it is also required under federal regulations. I'm a pilot.

Topgun2mo

My Feedback: (45)

And I love how if you happen to get Av Gas on your hands, you aren't stuck with that smell like regular gasoline. The smell just goes away unlike reg pump gas.

tkg

My Feedback: (1)

If your not running 8500 rpm on the ground, then most all the hop ups are useless. Porting, changing the exhaust timing all increase power, but they do it at higher rpms.
If your running a 22x10 and getting 7100 rpm then porting and such will REDUCE the RPMs at this speed. The same prop will be turning 6700 rpm. The G-62 is designed to run at 8500-9000 rpm.
If you need more power then get a bigger engine