Bullet Performance supercharger by Mercury Performance

[mastertech86]

[ame="http://www.youtube.com/watch?v=UbNgNcEfsUY&feature=youtube_gdata_player"]Mercury Motorsport Custom Tune: SUPERCHARGED Toyota 86 - YouTube[/ame]

[d1ck]

coheed you need to fix your posts from earlier. Power is a measure of work done per time interval. If an object is accelerated to 1 ft/s there is only work done while it is accelerating (negating friction). As long as the object is moving at a constant speed it uses no energy, therefore there is no work done, and no power required. Newton's first law in action people!

[Coheed]

Originally Posted by d1ck

coheed you need to fix your posts from earlier. Power is a measure of work done per time interval. If an object is accelerated to 1 ft/s there is only work done while it is accelerating (negating friction). As long as the object is moving at a constant speed it uses no energy, therefore there is no work done, and no power required. Newton's first law in action people!

Sure, if we were in space where gravity didn't exist [edit: practically isn't present], then Newton's law would be relevant here. But since we don't...

Calculations of hp won't work in space where gravity doesn't exist, since that variable is already worked into the original unit. Using this measurement in space to show 550lb 1ft/sec/sec acceleration doesn't compute correctly. HP is a unit that takes more into consideration than oversimplified newtonian physics.

[rice_classic]

Newton.. huh! What a simpleton! :P

[Coheed]

Originally Posted by rice_classic

Newton.. huh! What a simpleton! :P

I say oversimplified because people take it out of context. The fact that 550lb is a measure of gravity's affect on an object obviously means whatever you're trying to move is working against a constant force. It's not just some object floating in space without gravity's affects. Right?

With that taken into consideration: work is accomplished any time something moves against a force acting upon it. So by saying work is being done when moving a 550lb object 1ft/sec, obviously it cannot be assumed it's happening in a weightless/frictionless environment. So my original statements are correct.

[topazsparrow]

Originally Posted by Coheed

Sure, if we were in space where gravity didn't exist, then Newton's law would be relevant here. But since we don't...

Calculations of hp won't work in space where gravity doesn't exist, since that variable is already worked into the original unit. Using this measurement in space to show 550lb 1ft/sec/sec acceleration doesn't compute correctly. HP is a unit that takes more into consideration than oversimplified newtonian physics.

Umm.. gravity does exist in space... Every celestial body has gravity and is affected by gravity. Grade 8 science man.

[Coheed]

Originally Posted by topazsparrow

Umm.. gravity does exist in space... Every celestial body has gravity and is affected by gravity. Grade 8 science man.

True, but you won't see 1g will ya? Which is why you are "weightless". So while gravity still has a slight affect just outside our atmosphere, you would have to look at it in an entirely different scale, because lbs is too large a measure.

And remember gravity is only present when there is a rather large mass creating it. Without a mass, there is no gravity.

Once again, what I said is being taken out of context lol. I used the word "exist" instead of the word "present". So you are right there. Gravity still exists. It will always exist. But will it always be present? Sure, beyond what we can comprehend. Andromeda probably has some sort of effect on us, but we cannot accurately measure it lol.

[ahausheer]

Originally Posted by d1ck

coheed you need to fix your posts from earlier. Power is a measure of work done per time interval. If an object is accelerated to 1 ft/s there is only work done while it is accelerating (negating friction). As long as the object is moving at a constant speed it uses no energy, therefore there is no work done, and no power required. Newton's first law in action people!

Negating friction is key. Why are we talking theoretical physics? Lets focus on what actually happens to a car in the real world.

[ruskymx]

This thread is turning into a science class. Can't we all just agree that the delta on the same dyno is the most important part. Since we don't live in a vacuum, the difference in the baseline to the modded pulls are what's important.

Now back to your regularly scheduled programming....a force fed 86!

[Coheed]

Originally Posted by ahausheer

Negating friction is key. Why are we talking theoretical physics? Lets focus on what actually happens to a car in the real world.

That's the thing though, friction plays little part in the original measure of a hp. You don't need to negate friction in the measure of hp, but you need to understand hp correctly.

You aren't just moving an object across the ground, like others are assuming. Think of a 550lb weight on the ground, with a cable vertically strung over a pulley. On the other end of the cable is your car. As you pull the cable in your car, you cause the weight to lift off the ground and move. At 1ft/sec you are generating 1hp.

Most people think of just rolling a car along the ground, and that's not how to measure it because you aren't fighting the full force of gravity. With hp you aren't calculating a force acting on friction, but rather a force acting against gravity.

Take that 550lb weight and lift it 2ft/sec and you get 2hp, and so on. On an inertial dyno you take a fixed weight, and accelerate it. Using the drum weight and friction of the roller assembly, you can calibrate it to measure hp quite easily.

[ill86]

Unsubbed from science class.

[Coheed]

I'm hoping for 250whp on a setup like this. The roots should be able to supply that much, but I'm no supercharger junky. I just figured a setup like that would be responsive, and progressive, as long as temps stay low.

[d1ck]

I'm sorry coheed but you're wrong. horsepower is simply a unit of measurement of power just like watts. (1 horsepower = 746 watts). Power is measured by using work / time, or (force x distance) / time. The amount of work to accelerate a mass on earth is proportional to the following:
object mass & change in velocity
Object mass & change in height relative to gravity
Spring rate & change in spring length (only for when you're compressing a spring)
Non conservative losses (due to friction) (and radiation I think)
There's also some for heat if I remember correctly


Just to demonstrate why you're wrong lets do a simple calculation with your theory:
Your theory: 550 lb-m @ 1 ft/s = 1 HP
lets use the FRS travelling at 60 mi/h on a flat road and see how much HP that would require

(2900/550) x (88 fps) = 464 HP

Wow! That's a lot of horsepower just to travel at 60 mi/h!

Take that 550lb weight and lift it 2ft/sec and you get 2hp, and so on. On an inertial dyno you take a fixed weight, and accelerate it. Using the drum weight and friction of the roller assembly, you can calibrate it to measure hp quite easily.

I apologize that I missed this in your most recent post, and that is in fact correct. The unit of HP was created with this in mind, however, it's still just simple newtonian physics at play here and not as complicated as you previously suggested.

[ahausheer]

Lets move on, the only physics we care about is how much air we can cram into the engine. You guys can start a new thread. Cant wait to see dyno numbers. I wonder about the long term reliability however.