How many Kws of power does a car loose?

zippy320

Well-known member
Hi guys! I was wondering .

On average , How many kw of power does a normal car loose per year/ or Kms ?

Normal car , driven normally , not stressed , having its oil change and service done on time etc.

Or are there many factory's that come into play like driving style , maintenance etc? So a difficult question to answer?
 

shabba07

Member
From my experience, if a car is maintained properly, it wouldn't lose much power with higher mileage.

I can use my Honda S2000 as an example. My car has 153 xxxkms at the moment. It was a one owner car that was meticulously taken care off. My friends S2000 has 44 xxxkms. His car is an 08 and mine is an 06.

On the same day at the same dyno, on 2 occasions, my car made more power than his (for na its alot lol)

When he had exhaust and intake, and I had exhaust and chip, I made 6wkw more than him. On another occasion, I made 7wkw more than him(this time, we had the same intake, similar spec exhausts, but I had the chip) I was expecting my friends car to make much more than me because of the mileage. I think if your car is serviced and maintained properly, it shouldn't lose power. (Chip on a n/a car doesn't give much power, especially on an s2000)

Hope that helps.
 

Peter@AEW

BMWFanatics Advertiser
Official Advertiser
Current Cars
02 BMW E46 318i N42 Automatic
About 30% all things being equal.

93 Mercedes Benz W124 E320 4 Door Automatic
50% the day it left the factory

88 BMW E30 320I M20 Automatic
That car was the perfect petrol to noise converter never had any power from new

Above tongue in cheek :)
 

cOlDFuSiOn

New member
This is an interesting discussion! The classic Top Gear cheap super car challenge comes to mind :rollsmile:

If an engine is maintained, and parts replaced to make sure it is close to the spec it left the factory with then it should not loose power. Power loss is an indication of some wear, that is my logical approach to the question?

My car was dyno'd 18 months ago and made more than the factory spec, should go dyno it again to see, but environmental conditions are also always a factor. Hmm
 

Yuben

Senior Moderator
Staff member
My 10 year old stock 335i made slightly lesser torque on the wheels than a 340i makes at the fly as quoted.

Too many factors to consider on a dyno to accurately get an answer to your question :coolShake:
 

zippy320

Well-known member
Thanks guys!

@peter LoL thanks for that! hehe

@ cOlDFuSiOn I watched that episode and that's what made me wonder , how many horses have run away from my cars or on any car in general as it ages :)
 

TurboLlew

Honorary ///Member
With DI cars, the carbon buildup apparently becomes a problem... but I also dynoed when I bought the car and made 390+wkw (apparently wrong gear) and then about a year and 15000km later made 418wkw with 1000rpm to go because it hit the speed limiter in 5th which is the 1:1 gear. Nothing else changed except a cooler day I suppose (or car adapting to my driving style but I doubt that?)... or just dyno error/variance

I have the same experience with my non software S2000 with decat/exhaust/intake... right until I sold it, the performance at KAR was virtually identical (within margin of error and post mods) over 80000km/7+ years of ownership...

I've been told that my M5 will not be able to run with an E92 unless a carbon clean is done around 100000km... but I see no supporting evidence of this yet and don't know of any that have had this done personally.

As far as I can tell up to 100-120000km at least, in modern cars there is no drop off in performance.


zippy320 said:
Thanks guys!

@peter LoL thanks for that! hehe

@ cOlDFuSiOn I watched that episode and that's what made me wonder , how many horses have run away from my cars or on any car in general as it ages :)

those cars were not in great shape though
 

Ga-3M

Well-known member
That TopGear episode was such a load of nonsense! Using a mobile dyno to compare to factory figures. Nobody knows where the factory figures were achieved, what type of dyno they were achieved on, and so many other factors.

It's almost impossible to compare figures you achieve on a dyno here in South Africa to any factory quoted figures. As guys have said, in reality, if the motor is looked after and maintained properly there really shouldn't be any drop in performance up until and after 400k km I'm sure.

The only real way to check if your car is performing optimally is to have a bit of specific model history on a specific dyno like say KAR. For example, most gents with S54 motors that use that dyno know that healthy S54's make 175-180wkw, anything above that with a stock car and you have a very healthy specimen, anything below that say 160wkw and you know your car isn't running optimally and needs to be checked as it has lost some ponies from what it should be. Again not a 100% science due to different days, temperatures, conditions, but the closest you'll get to checking how well your car is running in my opinion.
 

325iSmk2

Banned
Llew said:
I've been told that my M5 will not be able to run with an E92 unless a carbon clean is done around 100000km... but I see no supporting evidence of this yet and don't know of any that have had this done personally.

:roflol: :roflol: :roflol:

I think the M5 would have to be running on one bank of cylinders only before it's as slow as the E92 M3 up here on the reef.
 

AndreasSA

Member
Peter@AEW said:
88 BMW E30 320I M20 Automatic
That car was the perfect petrol to noise converter never had any power from new

So true Peter! Even with manual box a horrible experience to drive....:hammerhead:
 

Fordkoppie

///Member
My old e30 323i only started to become a little down on power when it reached 350k. Up to then, it was as it should be.
But it was meticulously maintained all its life even though it was driven hard.
 

zippy320

Well-known member
LoL you guys are making it sound as bad as an E90 320i ... its not sooooo bad , I used to have lots of fun with it , Especially if you pressed that special button below the acc pedal . I love that little 6 cylinder M20 engine :)

Sigh , the special button on the E46 though does nothing .. Never tried it on the E320 .



AndreasSA said:
Peter@AEW said:
88 BMW E30 320I M20 Automatic
That car was the perfect petrol to noise converter never had any power from new

So true Peter! Even with manual box a horrible experience to drive....:hammerhead:
 
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