1:10th to 1:1 comparison power.

[donhd04]

Im just wondering on this and thought some of you all could help me out with it.

A GM LSX is 600hp and 620 ftlb torque out of the crate and 1:10th of that is 60hp and 62 ft.lbs. torque. Now what is the conversion (or better yet someone who is smart can figure it out for me if you want) to go from hp to electrical power?
Is electrical power rated in volts or amps?

And last but not least, what motor (holmes, tekin, castle etc.) would be equivelant to the GM LSX crate engine in a RC that is decently sized to fit 1/10 or 1/8th scale cars?

I know this sounds like a lot of power................and your right it is!!!!

power is like sex, you can never have to much.

[Armistice]

Watts= power. Volts= potential. Amps= current. I'm sure we all know what you meant

Motors seem to be rated in kV... so maybe that's what you want?

Anyway, here's a site that has the conversions and could help you

http://www.ehow.com/how_5059365_conv...mps-volts.html

With that I get 600*0.746= 447.6kW . For the next part, you need to know the volts to get the amps, so don't know what to do there since we don't have it

As for torque, it's just a conversion from ft# to in-oz. I used the 1/10 scale of 620ft# to get 62ft# and convert to in-oz= 11,904in-oz. The conversion from ft# to in-oz= 0.00520833333333...

Convert ft lbs to oz in - Conversion of Measurement Units

[donhd04]

Wow i really wish i had stayed in college now. holy crap. this get confusing.
so with 60 hp being 1/10th the hp of 600 i guess im looking for something around the 44.76KV range. Anyone know of anything with that rating?
I did get a tip from Harley on this one to run a TEKIN PRO 4 3300kv motor and a RX8 ESC. Anyone have any specs on that motor as to getting a power rating on?

[Armistice]

The 447.6 is in kW not kV. Like I said, you need to convert that. 447.6kW*1,000= 447,600watts

Next it's w/v=A, but we don't know the voltage or amperage, so can't do the equation. I may be missing something though

[Coops]

Perhaps you should take a quick step back and think of what you are proposing. If the power is say 1/10 or 60hp does that not sound like a decent size motor? Consider a push mower is in the 5-7hp range (gas but close enough for comparison). A 60hp motor would be slightly bigger than a lawn mower.

We can calculate this backwards though. Lets say you use a 3S lipo so 12.6V max, let's also assume you're using a ESC that has a max letthrough of 100A. That would be 1260VA or use watts for arguments sake power into the motor. Convert it and you get 1.68hp. This is all at max burst.

The next question is if you can simply use 1/10 for the conversion factor for power. I'm not sure if you can.

[speed ghilliesniper]

Originally Posted by Coops

Perhaps you should take a quick step back and think of what you are proposing. If the power is say 1/10 or 60hp does that not sound like a decent size motor? Consider a push mower is in the 5-7hp range (gas but close enough for comparison). A 60hp motor would be slightly bigger than a lawn mower.

We can calculate this backwards though. Lets say you use a 3S lipo so 12.6V max, let's also assume you're using a ESC that has a max letthrough of 100A. That would be 1260VA or use watts for arguments sake power into the motor. Convert it and you get 1.68hp. This is all at max burst.

The next question is if you can simply use 1/10 for the conversion factor for power. I'm not sure if you can.

This, you have to realize that that 600hp is used in a rig about 6000 pounds (rough estimate), so scaled down that would be a 600 pound rc truck. If you had a 600 pound rc truck you would need 60hp, but even the heaviest scalers rarely land any where above the teens. Just more food for thought.

[klampykixx]

just to add to Coops post, 1.68 hp would be roughly equal to 168hp in a full size being 1/10 yea?? but! what about the weight factor. power to weight ratios play a big part in this equation as well.

something that an LSX would be in, say a pontiac GXP (holden commodore for the aussies) 2000kg. now 1/10 of that should make for a pretty darn heavy RC!! 200KG!!! so when you factor in that the RC might weigh 5kg max, thats approx 5-8% of the "scale" weight... so what youre looking at is this:

(round numbers here)
2hp @ 5kg = 1hp/2.5kg

vs

600hp @ 2000kg = 1hp/3.3kg

so already we can see that the electric rc has a much better power to weight ratio which to equal it in full size would need 800hp to be equivalent to...

hope that made sense!!! lol

[sloppy]

You will find some pretty huge difference's going from electric to a combustion engine.. that will more then likely give you huge fits trying to scale this down on paper..

In 1:1 you would not replace your 600HP combustion engine with a 600HP motor to achieve the same end result.. I would guess you would go way down on HP with the electric motor for the same results..

[klampykixx]

but there is a big difference in the power curve of either engine also, where an IC engine actually builds power with revs, an electric motor has max power (usually) at zero RPM, so off the mark it has max available power. so next to each other would be massive differences in take off even with the same power figure.

[sloppy]

Originally Posted by speed ghilliesniper

This, you have to realize that that 600hp is used in a rig about 6000 pounds (rough estimate), so scaled down that would be a 600 pound rc truck. If you had a 600 pound rc truck you would need 60hp, but even the heaviest scalers rarely land any where above the teens. Just more food for thought.

weight is cubed to scale down..

so 6lbs for 6000lbs is 1/10 scale..

[klampykixx]

Originally Posted by sloppy

weight is cubed to scale down..

so 6lbs for 6000lbs is 1/10 scale..

wtf?

if something is one tenth of something else and that something else happens to be "6000lbs" one tenth of that is 600lbs, not 6... even if it were cubed, how do you get to 6?? 6x6x6 is not 6000......

but still, beside the point.....

to get a similar scale power in a 1/10 rc to something with an "LSX" would not specifically need 10% of the 1:1 power as its not 10% of the 1:1 weight. simple.

[Harley]

Wow, I think you are really missing the scale conversion of this. 60hp is NOT an accurate 1:10 conversion. You should be looking at power to weight for a better look.

If you want to use the LSX for a comparison. 600 HP, likely getting 300-400 to the ground if you're lucky with a big drivetrain like the Ultra4 cars run today.

Those cars are going to come in at somewhere around 4000 lbs. So say you go with 400 hp to make it easy. That is 10lbs per HP.

So a typical 8lb class 3 or TTC rig should have 0.8 horsepower.

[losikid]

Just for an idea here, 750 watts is 1 hp

The largest sensored brushless motor i've seen (in the 1/10 scale) would be the announced (but not released) holmes hobbies Puller Pro which was announced alittle over a year ago but jrh said 1600 watts i think, so just over 2 hp and it'll have enough torque and power to turn anything anything into shrapnel in a matter of seconds. 2 hp in a motor that only ways 9oz is an insane power to weight ratio

I'm sure if you really wanted to get a motor thats scale in size and weight you could get 60 hp, but from what we call 1:10 motors, you'll never get 60 hp. You'd have to go to like a 5th scale or something. I think castle has some 10k watt motors for the 1:5 scale buggies so it'll put you up in the 13.5ish HP. If you get Holmes to design and make a motor that big, you can probably get closer to that 60hp.

[klampykixx]

Originally Posted by losikid

but from what we call 1:10 motors, you'll never get 60 hp. You'd have to go to like a 5th scale or something.

but then to do a true scale 1/5 engine you would want roughly 120 hp to make it accurate so are in a completely different ball game....

[Coops]

Originally Posted by Harley

Wow, I think you are really missing the scale conversion of this. 60hp is NOT an accurate 1:10 conversion. You should be looking at power to weight for a better look.

If you want to use the LSX for a comparison. 600 HP, likely getting 300-400 to the ground if you're lucky with a big drivetrain like the Ultra4 cars run today.

Those cars are going to come in at somewhere around 4000 lbs. So say you go with 400 hp to make it easy. That is 10lbs per HP.

So a typical 8lb class 3 or TTC rig should have 0.8 horsepower.

This is what I was eluding to. Straight power conversion didn't make much sense to me.

As far as an electric conversion, check out this if you haven't already seen it.

WORLDS FASTEST street legal ELECTRIC CAR - YouTube

Electric motors have all their torque from the get go. Similar to racing an electric truck to a nitro truck. I'd expect the electric to take the lead off the line.

[donhd04]

Originally Posted by Harley

Wow, I think you are really missing the scale conversion of this. 60hp is NOT an accurate 1:10 conversion. You should be looking at power to weight for a better look.

If you want to use the LSX for a comparison. 600 HP, likely getting 300-400 to the ground if you're lucky with a big drivetrain like the Ultra4 cars run today.

Those cars are going to come in at somewhere around 4000 lbs. So say you go with 400 hp to make it easy. That is 10lbs per HP.

So a typical 8lb class 3 or TTC rig should have 0.8 horsepower.

I was hoping you would chime in. Your thread on motors for the wraith is what got me thinking about this. The rig I'm comparing to is roughly 3700lbs and has 720 hp. I'm liking the .8 - 1.0+ power range in a motor. I guess now the question is what motor is out there that is going to make that kind of power using a 11.1V 3S lipo and BEC? Are we talking the new NeoPuller from Holmes, tekin pro 4, or maybe something from castle creations? And are we talking making the switch to brushless and sensored?

[donhd04]

Originally Posted by Coops

This is what I was eluding to. Straight power conversion didn't make much sense to me.

As far as an electric conversion, check out this if you haven't already seen it.

WORLDS FASTEST street legal ELECTRIC CAR - YouTube

Electric motors have all their torque from the get go. Similar to racing an electric truck to a nitro truck. I'd expect the electric to take the lead off the line.

Wow what a video! That was 10 min of extremely good information and fun to watch.

[sloppy]

Originally Posted by klampykixx

wtf?

if something is one tenth of something else and that something else happens to be "6000lbs" one tenth of that is 600lbs, not 6... even if it were cubed, how do you get to 6?? 6x6x6 is not 6000......

but still, beside the point.....

to get a similar scale power in a 1/10 rc to something with an "LSX" would not specifically need 10% of the 1:1 power as its not 10% of the 1:1 weight. simple.

weight is 3 dimensional.. 10 Length x 10 Height x10 Width is 1000 6000/1000 = 6 need more help on this?? If you dont like the way I explained it you can google it or even search on this sight its been explained more then once..

[wesley89]

this this has given me a headache haha very very good info though

[losikid]

Originally Posted by klampykixx

but then to do a true scale 1/5 engine you would want roughly 120 hp to make it accurate so are in a completely different ball game....

Tell me, about how small can that lsx be as a running engine. Dimensions?

I kinda just inferred it, but our 1:10 scale motors are not 1:10 scale of a real engine. We'd have to go to like a 1:5 scale rc motor to get a more similar scale of size.