Topic: Dyno numbers between Cobalt and Kappa (LNF)

[Brazen17]

Sometimes up in smoke !!!!!!!!!!!!!!!

Kind of like the stock one buys for $100.00/share only to wake up the next day and see it is now $85.00/share. Where the hell did that $15.00 go? 

[kennysabarese]

It seems to me you can't just use a set % to get the whp. It works well for the horsepower ranges range we are dealing with but I don't see how it would hold at higher numbers. E.G. - 300 hp (crank)  - 15% loss = 255 whp. All things being equal except an increase in hp (say a tune and race gas) getting us 1,000 hp (crank) - 15% loss = 850 whp. Why does it take an extra 105 hp to move the same engine mass?  

This also assumes ( I know, I know) the engine is operating in the same rpm band (just different peaks for hp and tq). Where did the 105 hp go?

Stock C5 Z06 vette dyno

under 400whp

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[snaponbob]

Stock C5 Z06 vette dyno

under 400whp

C5s had 5.7 and 6.0 engines. Which one was this car? Any mods at all? Something else to consider - are the advertised power ratings legit? Remember the days of the 427/435? REAL horsepower was north of 500bhp, but for insurance purposes the engines were "rated" at 435.

[kennysabarese]

The point was to just show that as the bhp gets higher, the loss gets higher. If I have some more time I will find some more concrete examples.

[wspohn]

C5s had 5.7 and 6.0 engines. Which one was this car? Any mods at all? Something else to consider - are the advertised power ratings legit? Remember the days of the 427/435? REAL horsepower was north of 500bhp, but for insurance purposes the engines were "rated" at 435.

Actually, 'real' power was considerably less - that was back in the days of gross readings which tended to be around 15-20% higher than modern net figures. (I know, I know, I'm being pedantic....)

[Brazen17]

The point was to just show that as the bhp gets higher, the loss gets higher. If I have some more time I will find some more concrete examples.

Not sure what you are trying to say?

[kennysabarese]

Not sure what you are trying to say?

I was trying to show that higher horsepower cars have a larger difference between bhp and whp my example was not good. I will find others sometime. 

[Critterman]

Or             w  e      c o u l d     j u s t    l e t   t h i s    t h r e a d    d i e

[snaponbob]

Or             w  e      c o u l d     j u s t    l e t   t h i s    t h r e a d    d i e

But beating dead horses in the dead of winter is what forums are about ............ aren't they?

[JimVonBaden]

Personally I know very little about dynos, other than they vary with temp and humidity, and from dyno to dyno. This is all very interesting conversation to me.

Jim

[LatinVenom]

The problem is that people forget that Dynos should ONLY be use for tuning your car.

[Gentleman Jack]

But beating dead horses in the dead of winter is what forums are about ............ aren't they?

Perhaps I didn't beat my horse enough, it's still breathing...  Why does an engine that gets tuned to make more power use more power to spin the same components thru the same rpm range in all the same conditions?
what am I missing?

GJ

[snaponbob]

Perhaps I didn't beat my horse enough, it's still breathing...  Why does an engine that gets tuned to make more power use more power to spin the same components thru the same rpm range in all the same conditions?
what am I missing?

GJ

The same components that transfered low power are being used harder to transfer MORE power. Push your hand across your dining room table. Now push down on your hand and do it again.

[tazz]

The problem is that people forget that Dynos should ONLY be use for tuning your car.

Yes they do.
They also for get that the numbers are really meaningless unless your looking at where and when in the power band the vehicle is producing the power. 
A person can have a lower HP and TQ but if that TQ curve is holding near or close to the max(flatter curve) for a longer period of time they will be faster than a person with a higher TQ that peaks and does not hold near or at the peak.  TQ helps you get going and moving while HP helps you attain a higher top speed.
As for the rest of the discussion Well I'm not going to even say much since if I do I will certainly piss someone off and that's not my intention of any not my posts on this Information Board.

[snaponbob]

Oh, go ahead, Tazz. DO it.

BTW, you are 100% correct.