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Old 10-02-2003, 12:06 PM   #76
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Sean, might not be the same one but the book I have is the 5th Edition Automotive Handbook by Bosch. The ISBN number is 0-7680-0669-4. Any half decent book shop should be able to order it in from the ISBN number.

//Stu
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Old 10-02-2003, 05:45 PM   #77
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Still mis-understood.......

I didn't say the flywheel made or decreased, or increased compression, nor did it have ANY effect on compression. Merely that the flywheel carried kinetic energy, to keep the enging spinning to aid the compression stroke. I was theorizing that with a heavier fly wheel, you could increase the compression ( by different bore, stroke, valve life/duration/timing to increase power output without stalling the engine.

OK I was wrong. I do'nt know too much about these electric engines..
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Old 10-02-2003, 10:55 PM   #78
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Quote:
Originally posted by JesseT
Have you ever wondered why the motor is always placed so that the pinion is pointing to the right. This is simply to counter at least some of the inertia of the tires. BR/ JesseT
Actually, the reason the motor is on the left side of belt drive cars (pinion pointing right) is because of the forward rotation of the motor (since it is timed at 24 degrees, there IS a forward and reverse orientation) which is clockwise.

This clockwise rotation of the motor turns the spur gear counter clockwise (that's anti-clockwise to our non-North American friends) which is the same way that the wheels need to go (when viewed from the left of the car. . .)

If you put the motor in the right side of the car (pinion pointing left) then there would need to be some method of changing the rotation direction, which would add another gear (sapping efficiency) or something.

Occam's razor - simplest answer. . .
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Old 10-02-2003, 10:58 PM   #79
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Quote:
Originally posted by PitCrew
Still mis-understood.......

I didn't say the flywheel made or decreased, or increased compression, nor did it have ANY effect on compression. Merely that the flywheel carried kinetic energy, to keep the enging spinning to aid the compression stroke. I was theorizing that with a heavier fly wheel, you could increase the compression ( by different bore, stroke, valve life/duration/timing to increase power output without stalling the engine.

OK I was wrong. I do'nt know too much about these electric engines..
Same principle applies to nitros too - that's why it's recommended to change to the lightened clutch bell on the NTC3 - less rotating mass = quicker acceleration.
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Old 10-03-2003, 01:56 AM   #80
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Quote:
Originally posted by Boomer
(since it is timed at 24 degrees, there IS a forward and reverse orientation) which is clockwise.
Sorry, I just didn't understand what you ment by this. Can you please rephrase. I fail to see what the timing has to do with the rotation.
You are right that using gears and having the motor turn counter-clockwise (see, I write american english, since I'm not an englishman ) would easily lead to a construction where the motor axle is pointing to the right. However there have been numerous attempts to either replace the pinion/spur combination with a belt drive and have the motor pointing to the left or just utilize a clockwise rotating motor setup with the axle pointing left. Neither of these approaches ever worked really well since it makes the car push badly while accelerating.
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Old 10-03-2003, 05:36 AM   #81
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If you take an adjustable timing motor, and rotate the comm 180 deg, it will run backwards. with + on + and - on -.
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Old 10-03-2003, 05:39 AM   #82
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You are 90 correct, most race engines have a very aggressive cam profile and lift, which makes low rpms very rough. They either need a slightly hevier flywheel or a higher idle to keep running. given that racers had rotating mass, they will go for th lighter fly and rougher idle. races aren't run at idle.

If you ever go to a real track, this is why the divers are allways blipping the throttle at idle. To keep the car running.

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Quote:
Originally posted by PitCrew
Still mis-understood.......

I didn't say the flywheel made or decreased, or increased compression, nor did it have ANY effect on compression. Merely that the flywheel carried kinetic energy, to keep the enging spinning to aid the compression stroke. I was theorizing that with a heavier fly wheel, you could increase the compression ( by different bore, stroke, valve life/duration/timing to increase power output without stalling the engine.

OK I was wrong. I do'nt know too much about these electric engines..
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Old 10-03-2003, 09:24 AM   #83
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If you were to put the motor on the right side of the car, you would have to get it to rotate counter-clockwise, to match the rotation of the tires/belts.

Stock motors are built with timing in them - American stock motors are 24 degrees, I don't know what others use, but it may be varying amounts, still the same direction.

If you're running the motor forward (clockwise), this 24 degrees is advanced timing. If you're running the motor in reverse (counter-clockwise), it would be retarded timing. This would be very hard on brushes and coms and would be very inefficient and would not have very good performance.
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Old 10-03-2003, 09:25 AM   #84
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Quote:
Originally posted by sands
If you take an adjustable timing motor, and rotate the comm 180 deg, it will run backwards. with + on + and - on -.
Yes, you can. But you would make the car useless for stock motors which do not have adjustable timing. Stock is still a huge class, probably the biggest, and add 19T, which are also keyed, and it is pretty stupid to design a car that these motors cannot use. . .
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Old 10-03-2003, 10:04 AM   #85
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Quote:
Originally posted by Boomer
Yes, you can. But you would make the car useless for stock motors which do not have adjustable timing. Stock is still a huge class, probably the biggest, and add 19T, which are also keyed, and it is pretty stupid to design a car that these motors cannot use. . .
Yah, I didn't say it was a good idea, just that you can do it. I have done this on rc boats with dual counter rotating propellers. Works really well. On cars, it is pretty stupid.

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Old 10-03-2003, 11:43 AM   #86
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Quote:
Originally posted by sands

If you ever go to a real track, this is why the divers are always blipping the throttle at idle. To keep the car running.

Sands
The greater Lift and Overlap on a race Camshaft, causes poor Fuel atomization low speeds and consequently the intake system will load up with excess fuel. The "Blipping" is to help the Engine clear this out.

Our small R/C Nitro Engines have the exact same problem at idle with the excess fuel. Thus the "Blipping" again.

Last edited by popsracer; 10-03-2003 at 11:53 AM.
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Old 10-03-2003, 12:49 PM   #87
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yes pops you are correct it helps clear out the engine keeping it from loading up due to fuel stand of ( thats when fuel doesnt atomize and turns to drops and floods out the engine and stalls!) for the people that dont understand, thats why nitro cars stall at idle because of low idle!

sean the book is the sameone the rags has you can get it barnes and noble or walden books, or any major book seller
check with them because they always comeout with new editions i also think they might have a marine edition!
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