the automotive theory picard thread

NYSpeed Automotive
1

when you see something truly retarded to do with automotive theory share it here… (things like the famous “turbo drawing”)

I’ll go first:
bimmerforums:

so some friends and i were talking about cars and mods and what not…which brought us to an argument.

Assume you have a new car (so engine wear is not a factor) that is rated 300hp to the crank from the factory. Which of the following will add more HP to the engine:

headers
catback exhaust
CAI

I think none of these will make the engine more powerfull, regardless of the car’s make, model, year etc…

why? well i might be wrong but:

when an engine is rated 300hp at the crank, the car is actually less hp at the wheels. The percentage of lost hp varies from a car to a car depending on how well it is build (weight of wheels/tires/type of tranny/differentail…etc), and whether it is front, rear or all wheel drive. so, for the sake of the argument, lets assume we are working with a rear wheel drive car, which is given that looses 15% of its power when it is all stock. thus by specification would make the car to have around 255hp to the wheels…right?

so i have noticed that a lot of people make mods, thinking they make their engines more powerful, when they really only reduce the percentage of lost power between the crank and the wheels. in other words, if we add the above listed mods to the car, and the car dynos 265hp to the wheels after the mods, all it means is that the car loosed less than the original 15% of power…but the engine is still 300hp at the crank. yes it might be a bit fater, because of the increase in wheel hp, but the enigine remains the same. this is true for all bolt on mods out there…now forced induction, chip/software and other mods done directly to the motor, will change it’s output directly, but that’s a different story.

my point is that when people unstall stuff like that, they tend to say “ohh my car is 330hp because I installed this and that”, when it really isn’t.

do you guys agree with this argument?

2

WTF IS WRONG WITH THAT PERSON?

3

wow

really?

seriously?

4

every time I read it I find a new flaw or spelling mistake… I’m almost crying with LOL-tears.

5

all it means is that the car loosed less than the original 15% of power

:bloated:

i hate bimmerforums

6

that was a well thought out theory :lol:

7

I keep TRYING my hardest to give him the benefit of the doubt.

I wish that one of his listed mods was a transmission/clutch/rear-end modification. Then MAYBE I could say that yeah that he might have a slight tiny bit of a point(still horribly wrong though).

I just can’t begin to imagine the shock he will feel from the responses of the forum members over there.

8

lol

9

He is wrong.

10

11

I still don’t know what to post in that thread… I am just dumbfounded, and the worst thing is people were trying to agree with him

I do, however, hope that my latest round of mods will help with the parasitic loss that my car has.

12

The only part I would agree with is the 330 hp rating.
People speculate their HP all the time after changing parts without much real information.

How many fractions of a percent would a more powerful engine change driveline losses?
Is that something that is static with crank hp?

13

The plane will fly.

14

:picard:

15

If you drive in reverse the mileage will go backwards…