Weight reduction = horsepower gain

[jamesA]

That's what I'm talking about.

 

[eg6sir]

way off topic guys.. started on weight reductions/ horsepower ratios, now it on aftermarket vehicle modifications and warrantee voiding

 

[klyph]

Fill your tires with helium...

 

[jamesA]

way off topic guys.. started on weight reductions/ horsepower ratios, now it on aftermarket vehicle modifications and warrantee voiding

Yeah sorry, but the major points of the original topic have been discussed, and there will be more threads like this in the future.

Your grandkid will have this same discussion with B's grandkid.

 

[i_shift]

to the best of my knowledge it works like this
NON rotational mass removed (10 lbs) will FEEL like 1 HP gained
on a 3500 lb car.
but that goes up the lighter the car gets
cars less that 2000lbs every ten lbs FEELS like 1.12 HP

Rotating Mass (anything that spins before the tire rubs the pavment) removed WILL yield HP gains. even more so with the motor's part (flywheel, crankshaft, rods, pistons, balence shafts, and crank pulls yield a very good HP increace.

"There is an average of 2.7 HP gained from every pound lost off the crank shaft." - Unorthodox Racing

that number is less on acceseries NOT directly connected to the crank, but still very good, though I dont know the number

Fill your tires with helium...

I think Les Schwab Tires Actually does.

 

[93civicracer]

Wonder how much a b16 would produce if it was mounted to something like a segway where all it carries is your weight that's over a 1900 lb weight reduction.

 

[humblegumbo]

Yeah sorry, but the major points of the original topic have been discussed, and there will be more threads like this in the future.

Your grandkid will have this same discussion with B's grandkid.

Truth. However, I still have not located a simple formula for weight reduction = HP gain on non rotational components. One pound off the crankshaft yields 2.7 hp, okay. Several people have brought up the idea that 10lbs = 1hp, but I haven't seen a source cited for this rumor.

When B's grandkid has this discussion it'd be awful cool to refer him to this thread.

 

[klyph]

I have it here:
100 lbs of weight reduction = Zero HP
Removing weight from the vehicle (non-rotating mass) yields no horsepower gains. It can however increase traction problems.

 

[theonecomplicant]

What's amazing to me is how responsive the car is to little tweaks. I can totally feel the difference between a full tank of gas, 1/2, and 1/4...and she only carries ten gallons to begin with.

I'm not sure if this has already been said or not, if it has I'm sorry. One gallon of water is equal to 8 1/3 pounds and gas is about the same I believe and that is a fact (Kayaking Magazine)

 

[nightrider45]

here maybe this will help you out too. If you know your weight to the car and a estimate of the hp to the wheels. this program can let you know the range of our E/T of your quater mile run. Interactive JavaScript to Estimate ET for Quarter Mile using Horsepower

 

[humblegumbo]

Started working this out for myself, and I am not mathematically inclined, so here I am showing my work.

1991 Honda crx si
stock HP: 108@6000
curb weight: 2174lbs

ratio: 20.13 lbs/hp

removing 50lbs dead weight: 2154
new ratio: 19.94 lbs/hp
HP equivalent: 109
So that would mean, that w/ this particular car, 50lbs = 1HP.

For comparison, let's do 2006 Mustang. Grrrr....
stock v-8 HP: 300@5750
curb weight: 3488lbs

ratio: 11.62 lbs/hp

removing 50lb dead weight: 3438
new ratio: 11.46 lbs/hp
HP equivalent: 304.36

Well that sucks, huh? Doing some more math, I either need to bump up to 187hp or drop down to a fighting weight of 1254.96! Or some happy medium in between...hmmm....

Time to start whittling!

 

[jamesA]

Started working this out for myself, and I am not mathematically inclined, so here I am showing my work.

1991 Honda crx si
stock HP: 108@6000
curb weight: 2174lbs

ratio: 20.13 lbs/hp

removing 50lbs dead weight: 2154
new ratio: 19.94 lbs/hp
HP equivalent: 109
So that would mean, that w/ this particular car, 50lbs = 1HP.

For comparison, let's do 2006 Mustang. Grrrr....
stock v-8 HP: 300@5750
curb weight: 3488lbs

ratio: 11.62 lbs/hp

removing 50lb dead weight: 3438
new ratio: 11.46 lbs/hp
HP equivalent: 304.36

Well that sucks, huh? Doing some more math, I either need to bump up to 187hp or drop down to a fighting weight of 1254.96! Or some happy medium in between...hmmm....

Time to start whittling!

You can't work that equation backwards like that. Your horsepower is the constant in the equation. If you start doing that, then the real weight/power ratio on the Mustang between 304.36/3438 = 11.29. Which is 100% INCORRECT.

If math worked your way, e=mc² could never be solved because c = constant (speed of light). If you change the value of c, you fuck the entire thing up.

It's really that simple.

 

[humblegumbo]

<rant>

First of all:

Variable speed of light
From Wikipedia, the free encyclopedia

The variable speed of light (VSL) concept states that the speed of light in vacuum, usually denoted by c, may not be constant, for some reason.​

Secondly,
e=mc², so, if you know the values for e and m you can solve the equation for c. c²=e/m. This is basic algebra and shows the real power of this equation.​

Additionally,
curb weight of mustang minus 50lbs = 3438.
HP of said mustang minus 50lbs = 300@5750rpm
lbs per horse ratio = 11.46:1 (3438/300)
HP per lbs ratio = 0.0873 (300/3438)
Stock weight = 3488​

Solving the equation for the HP equivalent of dropping 50lbs from the mustang works like this: 3488*0.0873=304.5024​

Does it make sense now? ​

Finally,
I never really meant to say I was "gaining" HP. I didn't realize how sensitive everyone is to this phrase. I'm not saying that the new HP rating for the mustang is now 304.5 . What I am saying is that in order to obtain the power/weight ration of 0.0873 you either need to decrease the weight by 50lbs OR increase HP by 4.5024.
​

</rant>​

 

[klyph]

He's trying to quantify power/weight ratios.
Like, how much weight would I have to remove to achieve the same p/w ratio I would have by increasing 1 hp. Obviously this varies depending on what weight range you're talking about.

 

[klyph]

correct away, but he knows that he's not adding any HP, he is trying to correlate HP gain vs. Weight reduction.
He's not saying HP is gained, merely that weight reduction has a similar effect to an increase in HP.

 

[jamesA]

First of all:

Variable speed of light
From Wikipedia, the free encyclopedia

The variable speed of light (VSL) concept states that the speed of light in vacuum, usually denoted by c, may not be constant, for some reason.​

Secondly,
e=mc², so, if you know the values for e and m you can solve the equation for c. c²=e/m. This is basic algebra and shows the real power of this equation.​

Additionally,
curb weight of mustang minus 50lbs = 3438.
HP of said mustang minus 50lbs = 300@5750rpm
lbs per horse ratio = 11.46:1 (3438/300)
HP per lbs ratio = 0.0873 (300/3438)
Stock weight = 3488​

Solving the equation for the HP equivalent of dropping 50lbs from the mustang works like this: 3488*0.0873=304.5024​

Does it make sense now? ​

Finally,
I never really meant to say I was "gaining" HP. I didn't realize how sensitive everyone is to this phrase. I'm not saying that the new HP rating for the mustang is now 304.5 . What I am saying is that in order to obtain the power/weight ration of 0.0873 you either need to decrease the weight by 50lbs OR increase HP by 4.5024.
​

</rant>​

I don't recall ever seeing hp per pound ratios. You simply don't use it, so there is no need for it.

 

[klyph]

Well if someone seriously believed that removing the passenger seat would add horsepower to the engine, they are beyond hope.

 

[klyph]

If my posts seriously aggravate you, feel free to ignore me. It's a public forum, I'll post what I want. :kisses:

 

[klyph]

Hah! you clicked view post anyway! Gotcha!

 

[humblegumbo]

I don't recall ever seeing hp per pound ratios. You simply don't use it, so there is no need for it.

"Power to weight ratio" means "power divided by weight".
300 divided by 3488 equals 0.0873...this is how many HP are pulling each pound.

I just used it in the math you so helpfully quoted. Therefore, I needed it to solve the equations.

And what about the newbies who believe everything they read? Do you guys ever think about the fact that people who don't even have accounts read these forums?