Dyno talk - Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community

Rayme · 03-06-2013, 10:10 AM

Hi guys! I'm always up for some technical talk and this time around I'd like to start a discussion about dynamometers and some myth related to this, mind you I'm far from an expert but I'd like some input from everyone here.

One myth I see again and again is the percentage of power lost to the wheels.

This dyno shows 173 HP to the wheel (about 14% of drivetrain loss), If we take for granted this dyno is death accurate it means the car loses 27 HP through the drivetrain.

Could we safely assume this is a rock solid number right? If the car dynos another day at 250 WHP it would means the car is actually pushing 277 crank HP right?

ft_sjo · 03-06-2013, 10:16 AM

This is simple.

Chassis dynos are not considered calibrated devices for accurately measuring torque/power.

Reference figures are obtained by engine dynos.

The end.

Rayme · 03-06-2013, 10:24 AM

Quote:

Originally Posted by ft_sjo

This is simple.

Chassis dynos are not considered calibrated devices for accurately measuring torque/power.

Reference figures are obtained by engine dynos.

The end.

I guess my question would be is drivetrain loss an absolute number or a percentage. So this doesn't answer it.

03-06-2013, 10:10 AM	#1
Rayme The Answer Join Date: Sep 2012 Drives: Mazda 2 Location: Moncton, NB Posts: 1,233 Thanks: 488 Thanked 661 Times in 315 Posts Mentioned: 6 Post(s) Tagged: 0 Thread(s)	Dyno talk Hi guys! I'm always up for some technical talk and this time around I'd like to start a discussion about dynamometers and some myth related to this, mind you I'm far from an expert but I'd like some input from everyone here. One myth I see again and again is the percentage of power lost to the wheels. This dyno shows 173 HP to the wheel (about 14% of drivetrain loss), If we take for granted this dyno is death accurate it means the car loses 27 HP through the drivetrain. Could we safely assume this is a rock solid number right? If the car dynos another day at 250 WHP it would means the car is actually pushing 277 crank HP right? __________________ \| Roof wrap thread Last edited by Rayme; 03-06-2013 at 10:21 AM.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Dyno numbers list from Evasive Motorsports Meet/Dyno	Fish	Southern California	29	02-24-2013 04:16 AM
Cheap Dyno? Sponsored Dyno?	swift996	Mid-Atlantic	3	02-09-2013 01:29 PM
Dyno Compilation - dyno testing results and recommendations	Illusive	Engine, Exhaust, Transmission	82	02-08-2013 08:00 PM
BMW talk	RaceR	Other Vehicles & General Automotive Discussions	101	01-15-2013 12:32 PM
Base line dyno figure (dynapak Hub dyno)	gtauto	AUSTRALIA	16	10-08-2012 09:06 AM

03-06-2013, 10:16 AM	#2
ft_sjo Banned Join Date: Oct 2012 Drives: GT86 Location: The Motherland Posts: 1,398 Thanks: 140 Thanked 473 Times in 271 Posts Mentioned: 22 Post(s) Tagged: 0 Thread(s)	This is simple. Chassis dynos are not considered calibrated devices for accurately measuring torque/power. Reference figures are obtained by engine dynos. The end.

User Name		Remember Me?
Password