2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

Horsepower and wieght

Old Aug 16, 2004 | 08:27 PM
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Horsepower and wieght

I'm looking for a formula that can represent how many horses it would take to move lets say 10lbs of weight anybody know????
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Old Aug 16, 2004 | 08:45 PM
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Wow, there's so many variables possible there. It takes 0hp to move a 10lb weight if you drop it...
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Old Aug 16, 2004 | 08:49 PM
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Horsepower = Distance (in feet) X Weight (in pounds)
-----------------------------------------------
Speed (in seconds) X Constant (550)
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Old Aug 16, 2004 | 09:00 PM
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F=MA...force=mass X acceleration (change in velocity)

How fast do you want to accelerate this 10 lbs? That's the difference...
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Old Aug 16, 2004 | 09:32 PM
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1hp can more that 10 lbs.
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Old Aug 16, 2004 | 09:33 PM
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EDIT: move
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Old Aug 16, 2004 | 09:37 PM
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Assuming there's absolutely no initial friction or resistance to moving it, .00000000000000000000......1 hp can move it. It'll just move really really slow.
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Old Aug 16, 2004 | 09:40 PM
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yep
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Old Aug 16, 2004 | 11:16 PM
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When there was the big controversy about the 8hp difference with the RX-8, they figured out that it was equal to the extra weight of a 120lbs, i.e. having a girl passenger or not.
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Old Aug 17, 2004 | 01:31 AM
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Yeh, that rx-8 really disappointed a lot of people. Bring on the '06 rx-7 turbo!
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Old Aug 17, 2004 | 01:31 AM
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And a high output N/A version .
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Old Aug 17, 2004 | 01:49 AM
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well just think, those 5 and 10hp go carts move several hundred pounds pretty damn quickly, so 10lbs would be really small amount
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Old Aug 17, 2004 | 08:15 AM
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Originally Posted by version13
When there was the big controversy about the 8hp difference with the RX-8, they figured out that it was equal to the extra weight of a 120lbs, i.e. having a girl passenger or not.
If you look at in in purely power-to-weight terms then that's about right, but it's a bit misleading. A gain of 120lbs sounds much worse than an 8hp loss, but in fact it's only a 3.3% loss of power and a 4.0% gain in weight. Strictly speaking it's similar to ~100lb extra. In real terms it's a small change.

Last edited by NZConvertible; Aug 17, 2004 at 08:22 AM.
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Old Aug 17, 2004 | 04:23 PM
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Okay... so to move lets say a turbo vert in to the mid to high 12's about how much power would need to be made? I removed all of the a/c, ps, emissions, and anything else unecessary. the cars weigh what 3400lbs stock, so I figure I'm closer to 3000lbs now.
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Old Aug 17, 2004 | 04:26 PM
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Wow, you jsut love putting up impossible to figure out stuff. You can get a rough estimate, but what clutch, pressure plate, tires, do you suck driving, etc.
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Old Aug 17, 2004 | 04:39 PM
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well I don't suck in driving, I know how turn and judge corners as well as launch cars. Tires stock, bbs rims, but will upgrade to bigger rims but I'm considering to keep them for track days. Clutch and pressure plate stock for the time being... now I'm not trying to get in to a discussion about how parts I need but rather how much a car would need to weigh if it had roughly 350rwhp and was running about mid 12 runs.. is this even possible with a vert...
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Old Aug 17, 2004 | 04:42 PM
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speed = 234.742 multiplied by cube root of (horsepower/weight)

Found that online, haven't tested it. Try it out with some known figures and see if it works out.
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Old Aug 17, 2004 | 04:46 PM
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Saying its like adding 100-120lbs is kinda misleading. It is for acceleration, but weight also affects many other aspects of a cars dynamics. Such as braking, handling, fuel consumption, ect.
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Old Aug 17, 2004 | 04:49 PM
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very true, that's why our cars are awesome, they have great weight to power ratio as well as other goodies that most cars don't have... I'll have to try that formula to see if it works...
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Old Aug 17, 2004 | 05:15 PM
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I wouldn't exactly say the N/A's have a good power/weight ratio. Don't get me wrong, it's not bad, it's just not great. What rocks about our cars is the weight, not the power. Twisties > straight line.
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Old Aug 17, 2004 | 09:40 PM
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yeah but I have a TII in my vert... hehehe... so getting power is something worth my spending money
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Old Aug 18, 2004 | 12:22 AM
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its gona take alot of power to get to the 12's. the specific number realy doesnt matter.

keep adding power and other means of going fast (weight reduction, better tires/clutch, dont forget the roll bar/cage for sub 13-sec cars) and youle get there eventualy.

thats how you should be approaching this if you are serious. step by step. knowing some hypothetical # realy means crap if you dont have an idea how to get there, and more importantly how to use that much power without blowing the car up.

that aside. i'd say shoot for about 300 at the wheels. should be plenty.

Last edited by andrew lohaus; Aug 18, 2004 at 12:25 AM.
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