How to make a 4 stroke more HP

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sweetchassis#15
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How to make a 4 stroke more HP

Post by sweetchassis#15 »

G'day I have a Honda GX25 and I was just wondering what I can do to make it have for HP.
Could I do anything with the carby???
Cheers James
bentley marshall
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Re: How to make a 4 stroke more HP

Post by bentley marshall »

biger carb ,biger valves , cam timing , higher lift cam, roller rockers lol, up the compresion ,run av gas , ...

been looking for one of these for a project too will be intersting what ya can get out of it ..
sweetchassis#15
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Posts: 65
Joined: February 27th, 2010, 4:09 pm
Location: brisbane australia

Re: How to make a 4 stroke more HP

Post by sweetchassis#15 »

Thanks mate, I was thinking about running it on methanol I have two of them, I have a brand new one that im gonna run in my late model and the older engine is gonna be the test engine
bentley marshall
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Re: How to make a 4 stroke more HP

Post by bentley marshall »

ok i would get a biger carb one off a chainsaw maybe do a bit of porting in the head inlet and exhaust ..to start with
sweetchassis#15
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Joined: February 27th, 2010, 4:09 pm
Location: brisbane australia

Re: How to make a 4 stroke more HP

Post by sweetchassis#15 »

Thanks mate, pulled the old engine down in about 10mins lol. Tomorrow I am going to enlarge the inlet and outlet And get a larger carby. Is there any where I can get it dynoed?
jean phi
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Re: How to make a 4 stroke more HP

Post by jean phi »

Bonjours,

We in Europe, we work for 2 years on the GX35, it has more torque!

Work ignition (CDI), the original is not good to use RC.

Jean Phi
jean phi
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Re: How to make a 4 stroke more HP

Post by jean phi »

GX35 BigBlocRacing
Attachments
023.JPG
bentley marshall
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Re: How to make a 4 stroke more HP

Post by bentley marshall »

jean what ignition did you change to ??? and what spark plug are you using ??

i just bought a gx35 for a project (been looking for one for ages)
jean phi
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Re: How to make a 4 stroke more HP

Post by jean phi »

Hello,.

I changed CDI Honda by a CDI Zenoah (2 time).

Then he must remove the PIN on the motor wheel and give advance ignition (+ 5 °).

Attention the best engine performance is achieved only after 50 hours of use (long running).

If you want, j have a Carbon/kevlar ventilation carter.

For info I work in collaboration with HONDA EUROPE!

Jean Phi
bentley marshall
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Re: How to make a 4 stroke more HP

Post by bentley marshall »

thanks for the info jean will see how i go with it
Alkismurf
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Re: How to make a 4 stroke more HP

Post by Alkismurf »

Hi Bents, i've been reading up about these engines too.
Some of the mods people do are.
Replace the GX-35 cam with a GX-25 cam
Replace the GX-35 piston with GX31 piston


Here's a link. http://www.rcuniverse.com/forum/m_71680 ... tm#9462740
bentley marshall
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Re: How to make a 4 stroke more HP

Post by bentley marshall »

intersting stuff in that thanks smurf

what are you putin g one in ???
Alkismurf
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Re: How to make a 4 stroke more HP

Post by Alkismurf »

I'd like to put it in my drifter.....when i finish it lol, have you put one in a car yet?
bentley marshall
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Re: How to make a 4 stroke more HP

Post by bentley marshall »

no should be here today ....but i still have to build a chassis for it and finish the diff im building for it
jean phi
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Re: How to make a 4 stroke more HP

Post by jean phi »

We modified the wheel of ignition, a Honda Gx 25 wheel mounting.

Much easier to use, because we can now use a 54 mm and standard Bell clutch.

Jean Phi
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