Redline series 2 possible rwhp? And recommendations/ suggestions

[F1Aussie]

basically no, the percentages of loss works for a stock car.
if you lose 40kw on a stock car, the amount of power required to turn the accessories and drive train does not magically increase if you add power mods.
so people who mod retune and get xxx rwkw and then magic up their fw kw based on that stock loss % are full of it.

That is interesting. I had some mods done to my car just this week and that gave a rwkw increase of 22kw. Using only basic math skills I guesstimated that the baseline run gave a 18.9% power loss from engine to wheels. I thought using that same process to guesstimate the new engine kW would use a similar loss of kW to the rear wheels. So my guess was that a 22kw increase at the wheels was going to net about a 27kw gain at the engine. If this is not reasonably accurate do you know of a way to get a ballpark engine kW increase?

 

[RevNev]

I still get confused with the 30% loss from flywheel to wheels.. Does that gap close the higher up you go in HP ?
For example, a VF that pulls 1000hp at the flywheel wouldn't lose 300hp by the time you measure it at the wheels ?

Back in the day, the highest horsepower car we ran up was our 355 Holden V8 race engine that made 522hp on an engine dyno and 365hp at the wheels in a VR Commodore with a Hollinger 5 speed gearbox. That was a 30% loss much the same a stock VR V8 rated at 165kw (220hp) making 155/160hp at the wheels. It was later developed to make 640hp on an engine dyno and made 540hp at the wheels with the later "Shootout" software, a 15% drive line loss as the Dyno Dynamics dyno's read higher with software upgrades.

With the current Dyno Dynamic software, our VZ Supercar engine should make around 630hp on an engine dyno and makes 409kw (548hp) at the rear wheels. It's a 13% drive line loss in this example. We've got a VE ute kicking around modified 6 litre with a Magnuson supercharger on E85 that made 1000rwhp on a Mainline dyno, we haven't held a gearbox and diff in that car for long enough to run it up on the Dyno Dynamics dyno yet.

 

[Forg]

I personally don't really understand the losses through the drivetrain either ... surely the fluids would boil & the bearings/gears/unis etc would melt if they were dissipating that much power?

We know different manufacturers measure HP using different standards.

It's more that every single global manufacturer uses one standard, and tiny little local mobs like HSV chose strange old-worlde very-optimistic "standards" because nobody was really going to call them out on it.

 

[losh1971]

I think you will find an auto has slightly more loss than a manual, even though an auto seems to get the power to the ground quicker.

 

[07GTS]

its not a percentage loss as that means a 500hp engine with same gearbox/driveline swapped to 1000hp engine will loose double the hp and that is not accurate, it is a almost static loss of torque what ever effort the driveline takes to turn is what it looses

 

[Forg]

I think you will find an auto has slightly more loss than a manual, even though an auto seems to get the power to the ground quicker.

That’s largely user-related innit?
’Cos won’t a decent robotised-clutch box (eg. DSG) put the power to the ground quicker than a slushbox, and yet the method of power-transmission is the same as the “slower” manual?

 

[losh1971]

That’s largely user-related innit?
’Cos won’t a decent robotised-clutch box (eg. DSG) put the power to the ground quicker than a slushbox, and yet the method of power-transmission is the same as the “slower” manual?

Could well be, but I know with my 6L with M10, my take off are pretty damn slow and fiddly as it is hard to get it rolling, you could smash through the gears and slam the clutch but you would lose a few seconds if on the strip. Whereas you just stomp an auto and it's bang, bang, bang.

 

[Forg]

Could well be, but I know with my 6L with M10, my take off are pretty damn slow and fiddly as it is hard to get it rolling, you could smash through the gears and slam the clutch but you would lose a few seconds if on the strip. Whereas you just stomp an auto and it's bang, bang, bang.

Yeah, you’re human & don’t have your brain wired directly into the revs/fuel/speed/slope/etc in order to repeat the exact correct clutch actuation every time.
If you wired yourself in that way, you’d be beating DSG’s with your manual.
And you‘re nowhere near as boring either.

 

[RevNev]

If you wired yourself in that way, you’d be beating DSG’s with your manual.

BMW tested DSG's and manuals in their F Series M4 and the DSG beats a manual everywhere. The M4 GT4 race car has the road car DSG and they claimed with a manual, only a sequential dog box would match the DSG or DCT gearbox.

 

[Forg]

BMW tested DSG's and manuals in their F Series M4 and the DSG beats a manual everywhere. The M4 GT4 race car has the road car DSG and they claimed with a manual, only a sequential dog box would match the DSG or DCT gearbox.

A race car is for winning races, so it should have the fastest gearbox.
A road car should provide some level of joy though …