Anyone dissapointed with their W375 Package

[PeteSS]

I know when Harrop quote specific kits (300kw or whatever) they do have some sort of disclaimer saying that's how it was measured on a specific car using a hub dyno, then calculating what it would be at the flywheel, etc, etc.

I'd guess HSV is also a bit generous with their power figures. My boss got a Harrop stage 3 (530kw) upgrade on his GTS. After the mods it dynoe'd at 401rwk. Now I doubt the car loses 130kw from flywheel to the back, so the flywheel figure would be a bit less that 530kw. The gain (according to the dyno sheet) was legit, just the starting point I'm guessing is a bit lower. Whatever the power figures, this thing goes like a missile.

I just had OTR and tune on my 6lt. The dyno figure seemed a bit high (245kw), though at the end of the day I couldn't give a ****. The car goes and sounds a lot harder and that's all I look at

 

[Grennan]

Holden/HSV have proven to be fairly "optimistic" with their quoted figures. The GTS has been called out a few times.

A lot of people take dyno sheets as gospel. Theyve become a dick measuring stick when they were designed to be a tuning tool. Theyre absolutely ####ing useless when it comes to power readings because there are so many variables that come down to human intervention. Its funny that in the mid 2000s when LS1s were the bees dick of modded cars, a Tuned, OTR Exhaust LS1 was making 220rwkw. In 2016, people are waving around 240+ readings on those same cars with the same mods. Nothings changed. The mods are exactly the same. The engines havent got any newer. Whats changed? The mentality behind dyno readings.

The sooner people stop waving around their Tune and Exhaust dyno readings the better, but that wont happen because workshops use them as evidence of their work.

IMO, the best workshop is a shop that answers the question of how much power will it make, with "it makes what it makes".

 

[Husky]

I know when Harrop quote specific kits (300kw or whatever) they do have some sort of disclaimer saying that's how it was measured on a specific car using a hub dyno, then calculating what it would be at the flywheel, etc, etc.

I'd guess HSV is also a bit generous with their power figures. My boss got a Harrop stage 3 (530kw) upgrade on his GTS. After the mods it dynoe'd at 401rwk. Now I doubt the car loses 130kw from flywheel to the back, so the flywheel figure would be a bit less that 530kw. The gain (according to the dyno sheet) was legit, just the starting point I'm guessing is a bit lower. Whatever the power figures, this thing goes like a missile.

I just had OTR and tune on my 6lt. The dyno figure seemed a bit high (245kw), though at the end of the day I couldn't give a ****. The car goes and sounds a lot harder and that's all I look at

Autos lose about 33% from the fly wheel to the wheels, and manuals around 17%. So 530fwkw could easily become 401rwkw.

 

[Not_An_Abba_Fan]

The only time a dyno figure should be used is a before and after when doing work on the car so the customer can see where their money went. Otherwise, it's a tuning tool.

 

[PeteSS]

Autos lose about 33% from the fly wheel to the wheels, and manuals around 17%. So 530fwkw could easily become 401rwkw.

I always assumed the loss was a designated amount, not a percentage. if we went by 33% loss, a 1000bhp car (flywheel)would theoretically lose 330bhp to the back wheels ?


As far as power differences , reminds me of the days when HDT used to quote 188kw on the VK Brocks, but Holden quoted 137kw on the same engine. That's flywheel too

 

[Flukey]

A lot of people take dyno sheets as gospel. Theyve become a dick measuring stick when they were designed to be a tuning tool. .

I couldn't agree more, particularly when the power figures are quoted in HP. It sounds tougher again.

 

[Grennan]

I couldn't agree more, particularly when the power figures are quoted in HP. It sounds tougher again.

Its all about getting people artificially closer to the 500HP club.

 

[VS 5.0]

As far as power differences , reminds me of the days when HDT used to quote 188kw on the VK Brocks, but Holden quoted 137kw on the same engine. That's flywheel too

Not quite the same engine.

 

[Forg]

Not quite the same engine.

Plus a Brockowatt is a much smaller unit of measurement than a kilowatt ...

 

[Husky]

I always assumed the loss was a designated amount, not a percentage. if we went by 33% loss, a 1000bhp car (flywheel)would theoretically lose 330bhp to the back wheels ?


As far as power differences , reminds me of the days when HDT used to quote 188kw on the VK Brocks, but Holden quoted 137kw on the same engine. That's flywheel too

The faster you turn something, the friction there is going to be, in this case friction is power loss through the driveline. Like it has be stated, your boss should look at the before and after to see the gains, not just look at one number.