Trying to achieve dyno sheet numbers with cars

I heard some where there is a special mathematical formula for the prediction of horsepower in relation to torque... Well I'm not getting very realistic results. For example when designing a k20 engine with 138ft lbs of tq it didn't deliver any where near 197 hp.. Right now I am testing a vw r32 engine in the little golf and the number I was going for were 250hp and 232tq, following dyno sheets and taking into consideration the numbers you put in the file is not what is at the wheels.. The car with 232ft lbs of tq only makes 140 hp?.. Why does it do this, is there something I can change somewhere?

 

If your just wanting to know how to convert torque to HP here is the first result from google:

http://auto.howstuffworks.com/question622.htm

When your talking about wanting a specific torque and HP number for the car, you have to remember that those numbers are constantly changing based on the engine RPM. If you reproduce the torque/RPM curve and transmission gearing correctly you should have a realistic engine.

 

I understand that information my problem is that in game, setting the realistic tq values for a car does not produce the realistic horsepower values. Atleast in my mods.

 

I'm not sure if the HP number in the debug screen is HP at the wheels, or engine HP. It would make since for the numbers to be off if the game is using wheel HP, as so many other factors then just engine coding go into making the number. Here are the definitions of various HP ratings as per Wikipedia:

https://en.wikipedia.org/wiki/Horsepower
Nominal is derived from the size of the engine and the piston speed and is only accurate at a pressure of 48 kPa (7 psi).
Indicated or gross horsepower (theoretical capability of the engine) [ PLAN/ 33000]minus frictional losses within the engine (bearing drag, rod and crankshaft windage losses, oil film drag, etc.)
Brake / net / crankshaft horsepower (power delivered directly to and measured at the engine's crankshaft)minus frictional losses in the transmission (bearings, gears, oil drag, windage, etc.)
Shaft horsepower (power delivered to and measured at the output shaft of the transmission, when present in the system)minus frictional losses in the universal joint/s, differential, wheel bearings, tire and chain, (if present)
Effective, True (thp) or commonly referred to as wheel horsepower (whp)

 

BeamNG uses newtonmeters as torque unit, did you convert the "232tq" to Nm?

Engine friction and braking are reduced from the power even at full throttle, so you won't get the exact engine power by using real numbers. On the other hand, there is usually little or no power loss from engine to wheels in BeamNG, so 10-30% loss from friction and engine braking could have a realistic result.

 

You can actually get the real exact value by using real numbers When I was building my Cadillac, I managed to get peak hp within 1 hp of the real engine on the first try, at the exact rpm of the real engine too

 

Honestly I feel so stupid, Didn't know the game was in nm, smh... lol

 

Wow. Such accuracy. Very Cadillac. Much exact. Very myth. Wow.
(That is pretty lucky!)

 

I think i shall now update my cummins my hahaha.... Even with tq numbers in there it still pulls hard haha

 

You mean the torque curve in debug? It does calculate the power correctly from your torque values, but it doesn't take friction and braking into account. Try setting the friction higher than torque, the engine won't even spin in neutral. The current HP value in debug could show the actual power at wheels, not sure since it's so shaky.