About how many horsepower would a 30cc nitro engine make? I calculated about 40 horsepower but I might be wrong.

maybe 3, depends on what you do with it, exhaust, intake, any head work done.

Why would anyone really want to do that? The whole point of gassers is the cheap fuel cost. How did you calculate? Adding together a bunch of "1.5" horse small blocks?

deff, NOT no 40hp
p
think about it. a large lawn mower motor is only 3-8hp max...
a nitro is not gonna have no 40hp
more like 2-4 prolly closer to 3-3.5h

I thought the point was for people who found nitro tuning frustrating.......hehehehehehe.......

A dyno test of the OS 30VG shows 1.8 Hp, so if a 0.3 cubic inch engine (4.9 cc) makes 1.8 Hp, then a 30cc engine would make about 11 Hp.......if one can extrapolate like that. I'm not sure.

(30 cc x 1.8 Hp / 4.9 cc) = 11 Hp

i dont think the math works like that for real
in theory it does
because a 30cc weed eater motor has about 1-2 hp
i really dont think they have that much hp.

I'm not sure, but I think that might have been the point.....a 30cc nitro engine would make a lot more power than a 30cc gasoline engine.

there was a nitro 5th scale and it bombed
Savage 5T it never saw the US seeing they just slapped longer chassis plates on a savage XL.
All the vids of the sucker I seen it preformed miserably.

you cant compare 30cc 4 or 2 stroke gasoline powered motors to a theoretical 30cc nitro.
i can imagine it would be costly to run....with a gallon of nitro running $30

Output power is simply Torque*RPM/5252. You have two ways to generate boatloads of power. One: You make it put out so much torque it will twist the chassis. Two: You rev the nuts off of it. Our tiny little engines just can't make much torque, so they go the second route.


If your 30CC glow engine could rev to 20,000RPM, you'd probably be putting out quite a bit of horsepower. Definitely into the double digits.
Do you have any idea how cheaply made and how conservatively ported weedeater engines are? They are so pathetic that, if installed in a Baja 5B, they won't rev high enough to engage the clutch! I wouldn't consider them a valid comparison for this topic. I'd be more apt to compare the engine in question with something like the 5B's 26cc engine, or some of the purpose-built gasoline aircraft engines.

strictly speaking, if the displacement is 30.5cc ( a common size engine) and if we place our CFM rating @ 18,000rpm, which is an achieveable speed, the motor would be consuming 9.68 CFM per minute. breaking that down further, .013029015 pounds of air per second. follow? assuming we are at a nice fat tune, running rich enough for "maximum power" our ratio would be about 4.87:1 running 20% nitro 80% methanol. so by weight, we'd need .0026753 pounds of fuel, and that fuel would produce 23 BTU. running gasoline, with the same volume of air, we'd need .00104 pounds of fuel (significantly less) but we'd only produce 19.24 BTU.... 17% increase just on thermal energy alone. these formulas do not take into account the heat exaporation rates of methanol, as this fuel would absorb more heat out of the incoming air charge, making it cooler, and therefore allowing an engine of similar size to consume more air, as a cooler charge has higher density, and therefore weight.

Honestly if I were to design a glow powered 1/5 scale car, I would go one of two routes:

1: supercharged four stroke V8. There's no replacement for displacement, we know four strokes are generally torquier, and who doesn't like a good, throaty V8?


2: Make the car as light as possible. F1 cars can pull amazing acceleration because they weigh next to nothing. So if we were to us an existing powerhouse glow engine, say an OS 30VG, we could get acceptable performance out of our fifth scaler by simply making it weigh about what a typical 1/8th MT weighs and fitting a three speed trans. As far as the engine is concerned it's in a monster truck.

Could swear I have seen a couple nitro 5th scales.. ? Who knows lol..

Edit:

I knew I have at least seen one Anomie has a very cool 1/5th scale crawler! Youll have to check it out for yourself. [8D]
Click on the my models for her description.
[link=http://www.rcuniverse.com/community/profile.cfm?section=gallery&memid=172334]Anomies Gallery[/link]