More Power!

[bruceb58]

So then, I guess the idle mixture flow shuts off as you increase the throttle? Yes, No?

Pretty much yes. The only time there is a lot vacuum at the idle jets is when the throttle plate is closed or near closed. Once the throttle plates are open, very little fuel is supplied by the idle jets. The jets in the main venturi are what supplies the fuel.

As far as solid core spark plug wires are concerned, don't use them on electronic ignitions or engine with electronic fuel injection. I don't know first hand but there are reports of damage to these systems from the massive EMI.

plus, a waxed unpainted bottom,

By the way, wax slows you down too which is why racers actually lightly sand their hulls.

 

[aerobat]

I also suppose that it's only my imagination that my vehicle runs smoother, and better in the rain, or under load, and even pulls better then before with a good set of plugs, and solid metal core wires (as opposed to fiberglas strands with carbon over them as in "stock factory" wires)

correct, its only your imagination . like said the best plug cannot do more than ignite the mixture . the developing flamefront is dependent on compression and combustion chamber layout , not the plug which at this time already stopped firing.

you really can compare this to a candle - how bright it burns is not dependant what lighter you used to ignite it.

hopefully you are not an argumentative old man ...

 

[Yankeyspeed]

When Merc were experimenting with EFI on those engines, they managed to get about 15 horsepower more, but not for very long. 140hp is about the limit of that lower end... After that, it comes apart.

As for synthetic oil, it might add 1 or 2 hp, absolutely nothing that would be noticed with the 'butt-dyno' or the GPS. Speed increase uses the rule of squares. To double the speed, you need 4 times the horsepower. If you are getting 40mph with 140hp, then to get 80mph you would need about 560hp.... Even an increase of 5 mph would require an increase of around 60hp... And you ain't gonna get anywhere near than from that little 3 litre... even with through-hull exhaust (which BTW will sound terrible, like one of those 'rice-burner' car the young set 'drive')... or an exhaust tube rather than the bellows. Just not enough flow to warrant a change in any part of the exhaust.

Venting the prop will increase the acceleration at the bottom end, but actually DECREASE the top speed.

Chris....

So the GM 3 liter is at the ragged edge of coming apart? 15 horse more and they pop? I'm having a hard time with that.

 

[MikDee]

correct, its only your imagination . like said the best plug cannot do more than ignite the mixture . the developing flamefront is dependent on compression and combustion chamber layout , not the plug which at this time already stopped firing.

you really can compare this to a candle - how bright it burns is not dependant what lighter you used to ignite it.

hopefully you are not an argumentative old man ...

Thus, if you have a weak spark, or a strong spark at the plug, your engine will run exactly the same? I don't think so! One example is incomplete burn, the other is more complete burn.
By design, I don't know if an internal combustion engine can actually burn 100% of the mixture during it's firing cycle anyway?
Nah, I'm just a cranky old man .

 

[MikDee]

Pretty much yes. The only time there is a lot vacuum at the idle jets is when the throttle plate is closed or near closed. Once the throttle plates are open, very little fuel is supplied by the idle jets. The jets in the main venturi are what supplies the fuel.

As far as solid core spark plug wires are concerned, don't use them on electronic ignitions or engine with electronic fuel injection. I don't know first hand but there are reports of damage to these systems from the massive EMI.

By the way, wax slows you down too which is why racers actually lightly sand their hulls.

So, what your saying is there's not enough vacuum to draw fuel from the idle jets at WOT? I can't believe that.

Anyway, my Fast Electric RC boats actually get faster with turtle wax ice on the bottom

 

[bruceb58]

Using a regular resistor plug wire is not going to cause a weak spark. In fact, it actually probably helps by making the duration of the spark last longer. Bottom line, the ignition systems on modern engines provide more than what is necessary to fire spark plugs.

 

[bruceb58]

So, what your saying is there's not enough vacuum to draw fuel from the idle jets at WOT? I can't believe that.

Yep. Even if they did, the amount of fuel you could get out of them compared to what the main jet is delivering is miniscule.

If your main jets are set to the correct size, it doesn't matter anyway.

 

[MikDee]

Using a regular resistor plug wire is not going to cause a weak spark. In fact, it actually probably helps by making the duration of the spark last longer. Bottom line, the ignition systems on modern engines provide more than what is necessary to fire spark plugs.

Your putting words in my mouth bruce,,, I never said anything about resistor wires.

I was talking about an engine electrical issue causing a weak spark.
Back in 1969, I was the 1st in my neighborhood to run the new at the time Niehoff Stainless Steel resistor wires instead of the stock wires, in my new 1969 Dodge Charger R/T 440 auto! and as God is my judge, I could feel the difference in my "Butt Dyno"! You couldn't kill the spark, especially in inclement, damp, or rainy weather that I had issues with previously (Chrysler O.E.M. parts ). With these new Niehoff wires, the engine ran like a fine watch!

The best part is, I could listen to my AM/FM radio, with no static at all! Like Steeley Dan sings!,,,lol

 

[bruceb58]

Your putting words in my mouth bruce,,, I never said anything about resistor wires.

and solid metal core wires

You said solid core...which means they aren't resistor wires.

 

[MikDee]

Read my last post bruce "Niehoff S.S. core resistor wires!

By the way, most of todays outboards use solid core wires, but some don't suggest a resistor plug,,, a recipe for disaster!

 

[bruceb58]

Read my last post bruce "Niehoff S.S. core resistor wires!

My apologies...was going by what you said in post #20