crankshaft height

Old 08-16-2007, 04:18 AM
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meister
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Default crankshaft height

what is the correct height for an outlaw 10.5 car?
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Old 08-16-2007, 05:50 AM
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mcracecars
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there really is no "correct hight" for engine placement, lower and farther back is better to a point, but most cars have limiting factors, frame xmembers, firewall, rule restrictions...
what kind of car and what are you trying to do....
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Old 08-16-2007, 08:01 AM
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meister
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I was told that my motor was too low in the car and wondering if I should raise it. It is about 13.5 in. center of crank. It is a 67 Camaro Outlaw 10.5 car
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Old 08-16-2007, 09:06 AM
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13.5 too low..... who was the Einstine that told you that?? :shock:

what you got for suspension, give more info on the car.....much more....
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Old 08-16-2007, 01:47 PM
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exactley what i was thinking ED..my 67 Camaro is lower than this by a few inches.

Brian
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Old 08-16-2007, 07:23 PM
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i am confused. i thought you wanted the engine as high as posible for better wieght transfer to rear wheels. could sombody clerify
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Old 08-17-2007, 06:04 AM
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edvancedengines
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Higher engine moves center of gravity of the mass up which will give additional weight transfer to the rear when accellerating forward.

Moving engine and center of mass up will also raise center of gravity which can possibly negatively affect high speed handling if taken to the extremes, which is why now the NHRA rule book has placed a maximum limit of how high the crank can be from the ground. Pro Stock engines are very low to the ground.

When you move the weight mass upwards it has effect on the suspension settings as well, which can decrease the initial force of suspension reaction to the rear tires or decrease tire hit. So it is a trade off.

If you keep all bars the same and move weight up the bars will hit the tires less but the weight transfer will be greater once the car has begun accellerating and as the front comes up even more weight is transfered to the rear tires.

At times you see this happening in cars but not everyone is aware of why the front wheels keep climbing as the car is going further down track with the cars with high horsepower. It is the weight transfer keeps increasing to the rear the further up the weight mass goes and the quicker the car accellerates the high weight mass will tranfer to the rear even more which keeps the front up. lol.

I think I will come back and copy this and add it to my Chassis Article. Maybe someone would be hleped some by understanding why this happens. Man I wish I could think of and remember everything when I am trying to write articles.

Ed
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Old 08-17-2007, 06:46 AM
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sailplane
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wow thanks ed. i guess i never thought about the rest of the track. just the launch. daaa lol :lol:
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Old 08-17-2007, 09:44 PM
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Ed is exactly right. Another thing. Once the front wheels have reached a point where the last one up is putting no presure on the strip, you have 100% weight transfer. Any more weight transfer is impossible. 100% is all there is no mater how high you go. Going higher usually just results in a damaged pan.
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Old 08-17-2007, 11:39 PM
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edvancedengines
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Bubstr,
I believe you are incorrect but will not argue. I will try to explain my point and theory about this though. If I am wrong, then I am wrong.

I do believe it is possible to transfer more weight than you actually have by the force caused by the increased acceleration.

If the car was motionless and not moving forward at a rapid rate of acceleration, I would be 100% in agreement with you. It isn't. The mass is rapidly accelerating in a vector that is moving in a forward and upward direction when it would prefer to remain where it is and motionless. As the mass gets higher it becomes heavier to a point and is trying harder to go back to where it began moving, which means the mass of weight is transfering backward at the weight of the entire car but also add the rate of the weight mass at an increasingly higher center of gravity accelerating.

Maybe Mr. Billy can calculate an example of this. I can't I am a dummer.

Ed
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