New Idea for Getting up to Speed

[LEMMEDRIVEIT!!]

I was just thinking.

Would it be easier if, say, you had 2 nitro engines in a car. The first engine is geared with a two speed to push the on-road car to about 60-80 mph. Then, you could say that when that engine hits full throttle, you would set it so that you are only giving it half-trigger on the transmitter.So, for the second half of the trigger-throw,set it to give gas to the second engine, which is geared rediculously low, so that it wil brin hte car another 60 - 80 mph faster. Basicaly i'm saying use the first engine to get up to 80, then the second engine, geared lower, to pull it even faster.you could even go a third stage possibly with a third engine.

Just an idea. Tell me what you think about it.

[DualBL]

the first engine would over-rev, and blow.
-Nick

[Craps]

Why don't use a seperate controller and just let off the 1st motor letting the motor clutch disengage from the drive train when the 2nd motor comes up to rpm.

[1822]

Why not use the power of both engines at all times? More power for acceleration and top speed all the time.

[LEMMEDRIVEIT!!]

Originally Posted by 1822

Why not use the power of both engines at all times? More power for acceleration and top speed all the time.

Well, if your car weighs about 8-10 pounds, then why do you need to accellerate to 80 mph in an instant?You can use two servos. First servo throttles the first engine, and the second servo throttles the second engine. You use one channel to give the first engine full throttle, which pushes the car to 80 mph. Then you drop the throttle of that engine, switch it to the next channel, and start giving gas to the secon engine, which is geared higher and will be able to pull the car now that it is moving at 80 mph.So you go faster. This setup may be easier because you can use some type of two engine setup like an E-maxx, or the dual titan. This setup would be easier to gear because instead of getting huge gears made, you ciykd jut get a small spur, then a small pinion/clutch bell on the first engine, and a giant pinion/clutch bell on the second engine. This may even work better with two electric motors.

any other ideas?

[StevePond]

Both engines in unison would produce much higher speeds than a two-stage system. Lets say you have a pair of 3hp engines in a car. One engine pushes the car to 80 then you kick in another engine that's geared to bring it up to 120. You still only running on one engine, and that 3hp isn't enough to push the car to 120. This is the same as having a two-speed transmission with a significant ratio change. There's no reason to have the second engine if all you're going to do is shut off the first one; especially when it's needed the most. But, run both engines with a taller gear ratio and you'll have 6hp to push it up to speed and enough horsepower to overcome the massive aerodynamic drag of traveling over 100 mph.

[LEMMEDRIVEIT!!]

True, but its just another idea that I'm just throwing around.

Any Other comments?

[mgs9]

i think if it were done with eletric brushles motors it would work better, like if you had 2 motors on the same axcel one geared high and one geared low. the motors would have to be brushles because the other motor would be spinning freely. when you get up to you top speed with the first motor you can kick in the second motor witch is already spinning so you dont lose speed waiting for the motor to catch back to speed.
With gas you couldnt run both on the same shaft or what have you so you would have to wait a second or two for the second engine to get up to speed and you would lose speed during this time.

[StevePond]

It's the same scenario whether it's nitro engines or electric motors. It sounds cool to have a second motor kick it when you hit the "NAWS" button so it can burn rubber off into the sunset , but simply having both motors or engines engaged and pumping at the same time will produce better acceleration and higher top speed. Use both motors/engines at the same time, or just use a single big ass engine/motor and install a two-speed transmission. That's my $2.37.

[24601]

What about a tranny like the E-Maxx tranny. The 2 speed at the clutch, but then a two speed tranny to go the extra kick. Seems you are in need of more gears, not more engines.

[mgs9]

I didnt know the E-maxx had a trany, i know the t-maxx dose. havent realy seen any transmisons for eletric cars and trucks . of course the newest mag is from like march of 2002.

[Mike Keeney]

Originally Posted by StevePond

It's the same scenario whether it's nitro engines or electric motors. It sounds cool to have a second motor kick it when you hit the "NAWS" button so it can burn rubber off into the sunset , but simply having both motors or engines engaged and pumping at the same time will produce better acceleration and higher top speed. Use both motors/engines at the same time, or just use a single big ass engine/motor and install a two-speed transmission. That's my $2.37.

Actually, there is a bearing called a 'Roller Clutch'. It is essentially a one way only bearing. The neat thing about them is that they allow the shaft to free spin if the rpms exceed how fast the motor is turning.

It's better explained like this: A two motor setup. One is stronger at lower rpm, the other is a top speed motor only. Both motors share the same drive shaft. (Probably the back axle). You put the gas to the low speed motor and it will drive the axle and get you up to a speed the second motor can use. The high speed motor can idle while the low speed motor is doing it's thing. Since the shaft is turning faster than the high speed motor's sprocket, the roller clutch allows the shaft to spin freely. When you hit the gas on the high speed motor its sprocket will quickly catch up and pass the max rpm of the low speed motor. When that happens, the sprocket of the low speed motor simply free spins without creating any drag whatsoever on the other motor, (other than weight).

Personally, I would hit the gas on both motors at the same time. The high speed motor would give some beneficial force to what the low speed motor is doing. As soon as the high speed motor gets on the pipe it will propel the vehicle on its own.

I think about this kind of stuff all the time. Gawd I need a life!

Mike

[Hz-R]

Wouldn't it just be easier to mount one big block, big horsepower engine in the car then trying to build some complicated 2 engine transmission system? I'm not sure, but they make engines for model airplanes with a lot more displacement than your average car engine, guess they put out more power too. Saves you the hassle of trying to tune 2 engines as well! Just made me think of the old 'KISS-principle' (Keep It Simple Stupid!) :-)
On the other hand I'm curious what cool constructions people come up with!

And Mike, I think you shouldn't have to worry too much about 2 engine set-ups, think you have more than enough power with that V8! But I guess too much power is just about enough for this contest! btw. I can come up with worse things to think about! ;-)

Robbert

[cianhanrahan]

I think the problem with Aero engines would be that even though the quoted HP is higher they Rev lower, so mating a tall auto transmission to an aero mill would be the hard part.. Actually I'm surprised Air engines are only mentioned now, I would have thought, like yourself, that they were an obvious powerplant choice. either there's something I haven't been told, or everyone's holding out on us..

[Hz-R]

I really wondered about that as well. I read about all kinds of motorbikeengines to turbine engines, but somehow a lot of people seem to want to stick to .12 and .21 engines.. Sorry if I blew the secret! :-)
Guess cooling might be a bit of a problem too, although, at 200MPH that some guys have in mind... :-)

[crank throw wei]

Steve is right on the money.Using the 2nd motor for assisting the first is the thinkin' man's way too go.That way,all the power is available to drive the wheels.Save the one-way bearing for your pull start.

The problem with the aircraft engines is the low revs.Many of the larger ones have piston rings,which tend to flutter at higher revs.And the car engines are much more developed,thus,make more power.

[EddieWeeks]

Its not a matter of how much HP.. The key to going fast is to put HP
to the wheels over a very large RPM range.. Nitro engines only have
a high HP for a small range of PRMs. Electrics have more range of RPMs
but the key to this whole thing is to produce your max HP to the wheels
at your max speed.

Every car should have a designed max speed. At that speed your Nitro or
electric should be produceing the max HP.. As you all know you will have
to gear it to the moon to do that... But that is what it takes to be efficent and fast.

Sounds like to me you all just needs lots of gears..

Eddie Weeks
btw... I started a new Web page on the building of my turbine
powered car..

http://bellsouthpwp.net/w/e/weeks1/car.html

[nitrosportrules]

Originally Posted by LEMMEDRIVEIT!!

I was just thinking.

Would it be easier if, say, you had 2 nitro engines in a car. The first engine is geared with a two speed to push the on-road car to about 60-80 mph. Then, you could say that when that engine hits full throttle, you would set it so that you are only giving it half-trigger on the transmitter.So, for the second half of the trigger-throw,set it to give gas to the second engine, which is geared rediculously low, so that it wil brin hte car another 60 - 80 mph faster. Basicaly i'm saying use the first engine to get up to 80, then the second engine, geared lower, to pull it even faster.you could even go a third stage possibly with a third engine.

Just an idea. Tell me what you think about it.

`*`*`*`*`*`*`*`*`*`*`*`*`*`*`*`*`*`*`*`*`*`*`*`*`* `*`*`*`*`*`*`*`*`*`*`*`*`*`*`

just go with 2 motors runnings at the same time and hook up a hardcore racing t-maxx tranny then hook that to annother then presto 4 speed gearbox('s).

[jordan29]

That wouldn't to to well with to much space taken up and the similiar gear ratios.