Will my system slow me down much?

[4geze63]

I am soon going to be putting a 15" Power HX2, in a good sized ported box in my car.

Sub 45lbs
amp 12lbs
box 60 lbs

and my optima blue top which is allready in weighs 60 pounds, 30 more then a normal battery.

So thats 117lbs extra pounds in the hatch and 30lbs extra in the front.

Im a FWD and I only usually race from a roll, so would this extra weight make a noticable difference on how my car will pull when I step on it from a roll.

I figure if it was in the 1/4 I would lose around 1.5 tenths.

mods in profile if needed

 

[DSMSpyder99]

from a roll it will make a difference like if you had a passenger. At a drag strip it would make a HUGH diffence, transfer weight is an enemy for FWD and add 100+ lbs. in the rear is not a good thing

 

[Ryans99OZ]

2 tenths....the general rule is a tenth for every 50 lbs...

 

[VOTBLINDUB]

u race or do serious sound, theyre opposite in terms of what u want with weight. u need to pick one

 

[a_scobel]

2 tenths....the general rule is a tenth for every 50 lbs...

I've always been told that it's one tenth for every 100 lbs....

 

[CowPimp]

I've always been told that it's one tenth for every 100 lbs....

I've heard the same, but both figures are nonsense in my opinion. A simple equation will give you a better idea of what you stand to lose in terms of performance:

R = W/P

R = Ratio (Pounds per HP)
W = Weight
P = HP

W = 2791 + 180 = 2971 (Car + Driver)
P = 195
R = 15.24

Do the same for the new weight:

W = 2791 + 180 + 117 = 3088
P = 195
R = 15.84

Now, see what the HP loss is if you had the same weight:

15.84P = 2971
P = 187.56

So, on a stock car, it would be as though you lost approximate 7.44 HP at the crank.

 

[4geze63]

my car is pretty fast anyways even with a 170 lb passenger so im not really worried about the overall speed, I just want to have a sub in my car