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orion
11-06-2012, 04:44 PM
So as I delve further and further into my interest of cars, the topic of power to weight ratio has come up. Yes I understand you take the HP and divide it by curb weight of the car, that provides the number, but what are the advantages of cars closer to zero, to one, or above one( if it might exist). the purpose being, I'm building my 240 to be a good all-rounder, I want to be able to have fun with it, touge/track/drift any of it. A friend of mine told me that i want to have as close to a 50/50 power to weight ratio as I could and he confused me. What is the best ratio number to have in order to handle the best and still fast coming out of corners and on straights?

I just hope to further understand the concept.

roboticnissan
11-06-2012, 04:54 PM
Power to weight and front and.rear balance are two different things.

Power to.weight refers to like a 4000lb car with 200hp being just as fast as a 2000lb car with 100hp.
( a little more complicated than that but its the general idea)

50/50 refers to your weight of your car being evenly distributed front to back.


You want as light a car as possible with the most power, but you want the weight evenly spread across the body

jr_ss
11-06-2012, 05:37 PM
50/50 is even distribution. The more power and the less weight is preferable, however, it doesn't always mean your car is faster. Traction is a huge key.

orion
11-06-2012, 06:30 PM
50/50 is even distribution. The more power and the less weight is preferable, however, it doesn't always mean your car is faster. Traction is a huge key.

I figured as much, so too much power combined with a lighter car could cause loss of traction, and thus crappy handling/launch. So I guess my next question would be how much is too much, as far as the s14's go. I already have a reasonable goal of 250 hp to have some fun with, but I'd also like to know what kind of ratio numbers have been the best as far as track type events.

roboticnissan
11-06-2012, 06:34 PM
When you wanna speak specifics its gknna come down to driver preference. Drive your car the way it is and make changes slowly. Having too much weight or too little weight will require different driving techniques. Just get out there and drive.

ILoveJDM
11-06-2012, 07:10 PM
you're not really using the right numbers here.

50/50
^-- this is a weight distribution divider with a value out of "100". 50% weight in the front, 50% weight in the rear. This makes the car evenly balanced and easy to predict. a 60/40 would be 60% front,40% rear. a heavy front engined car will usually have understeering characteristics. many things start happening when you start taking the car around corners while braking and transferring weight side to side.

50:50
^-- proper power to weight ratio, this is also just "1:1" or, 1hp per 1lb. or "1."

a car with 500hp, that weighs 2000lb, will have a power to weight ratio of 0.25, or 500/2000.

The higher the number - the better.

Lets see why people love boosted honda civics:

1996 honda civic - factory curb weight.
2300lb, 300hp. = 0.13 power to weight.

1993 dodge viper - factory curb weight
3200lb, 400hp = 0.125 power to weight.

You can see the Civic has a higher power to weight ratio, meaning it will require less horsepower to move the weight of the car, or it has .13 hp to move the same amount of weight (1lb) vs the .12hp of the viper to move 1lb.

what is really going to matter though, is your gearing.