The proper way to modify an engine cheaply

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karl

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1. High flow air cleaner
2. Long straight pipe 12-15 inches
3. Bypass governer
4. E3 spark plug
5. Port intake and if you can exaust
6. Shave the eyebrows if briggs flat head
7. New piston rings to bring back stock horsepower
8. Lap the valves
9. Shim the valve springs
10. High octane gas if you milled head or use thinner head gasket
11. Mill the head but that costs money
12. Re Jet if necessary
13. Thinner head gasket

THIS IS A LIST I KNOW THEY ARE NOT COMPLETE SENTENCES

These are most CHEAP mods to an engine I will not post any replies I want to know what you think
Hopefully we can agree on something
 

CriticalMass

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That isn't really the proper way to mod anything. That's just a list of mods that can be done. Also it would help to spell check your work.
 

CriticalMass

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I'm all for people learning and expanding their own knowledge. Proper punctuation and complete coherent sentences will do people good. I can understand the occasional missing letter, but throughout the message basically ruins the post and I stop reading.
 

Doc Sprocket

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The new rings are assuming the old ones are worn, in which case a honing is probably in order. That's not what I would consider a performance mod so much as maintenance. Many times, we are modifying an engine that's in good shape already. I have just taken a brand new clone out of the box, ran it at idle for about two minutes to make sure everything was okay, and tore it down. Did a governor delete, throttle mod, and low oil sensor delete. Intake, exhaust and re-jet (yes, I'll be drilling the jet) are next.

Regarding re-jetting (again), if the high-flow intake and exhaust is done, more fuel will be required, making rejetting a requirement.

For the record, may people start modifying engines and run into trouble because the mods are done in the wrong order, and/or out of "balance". All the parts need to work together in order to work properly. I would not necessarily consider this list to be in order, or balanced.
 

r_chez_08

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Just remove the gov. removes risk of it breaking up in there, and allows higher revs.
You can also go billet, and use proper valve springs.
 

slideways

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E3 spark plugs are garbage. JMO.. they foul like crazy.

Seems like you have parts and pieces for several different motors there. If you need to use valve shims.. just get stiffer springs. If you aren't removing the governor.. those other mods are pretty much worthless. Also if you are keeping the governor more spring pressure means nothing.
 

DCProductions

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Cutting every other blade off of the flywheel fan is an easy mod I have done to my engine. It was a plastic fan though; I don't know how cutting the metal ones would work. It is a decent list, though I think AGK's "performance basics" is more comprehensive.
 

88s10Durango

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I myself don`t feel that cutting the fins off the flywheel is good ? Would give somewhat less cooling , second could throw the flywheel out of balance , the governor might not work correctly if it works off the air flow from the flywheel ??
 
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DCProductions

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I'm running a gx200 clone. I have and have had no over heating problems and I run offroad most of the time. The fan is the only thing that cools the engine, and there is still good flow, so I love this modification (supposedly up to 1/4hp?- nr-racing.com). Regarding the balance, the fan is plastic, so any variation in its weight is insignificant to balance. Regarding the governor... no... just no. I don't run a governor, and governors don't run off air flow (at least on any honda engine).

Metal flywheels might change balance when you cut the fins off, but I wasn't careless when I cut them. They are even and sanded down. I would assume with patience, a good eye, and the right tools, anyone could do this to their fan.

I suppose this mod would only be useful with high rpm engines. If you notice, ARC flywheels have half the number of blades than a regular plastic fan.
 

DCProductions

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I am interested in the suggested header length. Does anybody have any comments on the best exhaust length (with or without curves) or is the list spot on?
 

devino246

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I am interested in the suggested header length. Does anybody have any comments on the best exhaust length (with or without curves) or is the list spot on?

If I remember correctly, the best way to do it is to leave the pipe longer and paint the whole thing. Run the engine for a few minutes and then cut off the part of the pipe that had unburned paint on it.
 

slideways

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Do NOT ALTER A CAST FLYWHEEL... DC is basically correct that the plastic mod won't affect durability. I doubt the hp gain however little it is. Adding tape to the blower housing will do more but you have to have a head temperature gauge and such.

Header length depends on engine also.. and the modifications, jet size and about 20 other things. You can't just come on a message board and say how long every header in the world should be.
 

redsox985

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Some people bug me terribly. I don't know much about headers or exhaust specifics to improve performance, but I know for a fact that it isn't "one size fits all". That's why I don't go out an spew my baseless, fact-less "KNOWLEDGE" as if it were proven true.
 
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