E-penis size thread

[Akane]

I prefer rolling road dynos, because it's power at the treads that matters, not at the hub.

[Bling]

Does it really matter though? I mean excluding for street cred

Seems like it used to be my car has XX Kw, but now it's my car has XX kW, but on a low reading dyno, so its better..... pretty sad / grasping for straws if you have to mention that imo.

[solitaire]

Does it really matter though? I mean excluding for street cred

Seems like it used to be my car has XX Kw, but now it's my car has XX kW, but on a low reading dyno, so its better..... pretty sad / grasping for straws if you have to mention that imo.

Dont forget about it being a hot day...

[metal_sean_head]

I prefer rolling road dynos, because it's power at the treads that matters, not at the hub.

Only for wank factor. Dyno's are more of a tuning tool and to see power progress on the same dyno.

[Bling]

Dont forget about it being a hot day...

True forgot that point.

Also don't forget "XX Kw on hub dyno, will have more power though as had shit tyres on so was probably slipping heaps"

[Lith]

I prefer rolling road dynos, because it's power at the treads that matters, not at the hub.

Dynos aren't desgined for bragging rights - they are for tuning. Rolling roads are poos for guaranteeing that engine speed is relative to rollerspeed. I prefer not to run mine on rolling road dynos now as my car has a patchy history with them (first Toyspeed megameet was one of those). I don't feel like I can fully believe what the dyno is telling me is really happening.

Example, if you have facebook:
http://www.facebook.com/video/video.php?v=150291538325257&oid=322984464432

Resulted in a dyno plot with loopdeloopsd - car never feels like it does loopydeloops on the road though, unless you do something really silly.

[Akane]

I prefer rolling road dynos, because it's power at the treads that matters, not at the hub.

Only for wank factor. Dyno's are more of a tuning tool and to see power progress on the same dyno.

Thought we were talking about which dyno people preferred on reading higher or lower. But alright

Dynos aren't desgined for bragging rights - they are for tuning. Rolling roads are poos for guaranteeing that engine speed is relative to rollerspeed. I prefer not to run mine on rolling road dynos now as my car has a patchy history with them (first Toyspeed megameet was one of those). I don't feel like I can fully believe what the dyno is telling me is really happening.

Example, if you have facebook:
http://www.facebook.com/video/video.php?v=150291538325257&oid=322984464432

Resulted in a dyno plot with loopdeloopsd - car never feels like it does loopydeloops on the road though, unless you do something really silly.

Dyno is for both bragging rights and tuning, where do you think the term dyno queen comes from?

Your experience with them is quite unfortunate tho........

[metal_sean_head]

Dyno is for both bragging rights and tuning, where do you think the term dyno queen comes from?

Your experience with them is quite unfortunate tho........

Bragging rights really only if the cars are tested on same dyno in same conditions. But i know where your coming from

[tsoob]

I prefer rolling road dynos, because it's power at the treads that matters, not at the hub.

explain the difference...?

[Akane]

I prefer rolling road dynos, because it's power at the treads that matters, not at the hub.

explain the difference...?

When you're measuring at the hub you're not factoring in the inertia of the wheel and wheel diameter and the power absorbsion of the rubber.

You're driving on wheels, not hubs.

[rollaholic]

i kinda get it, but dont see the point myself - its kinda like penis size, you have what you have, comparing it to others aint gonna make yours bigger / better. just enjoy it!

besides, lap times / quarters etc are what count in my book. power is only part of the equation!

[Mr Ree]

besides, lap times / quarters etc are what count in my book. power is only part of the equation!

Exactly^^

The clock doesnt lie, and there are many many cars out there with comparatively big output that would be eaten alive by smaller cars with half the power.

I had my car dyno'd recently and while it was nice to see big increases in power with each change that was made to boost/timing etc, I dont see the need to run out and put a sticker on my cars 1/4 window, claiming I have XXX kw's. Its a good way to be embarrassed lol

[pjay]

I live my life a quarter mile at a time.

[Silent Knight]

I live my life a quarter mile at a time.

Why...? Orgazms last longer!

[eskimo]

I give my wife a quarter inch at a time.

Couldnt resist sorry.

[Luke - BZG]

Does it really matter though? I mean excluding for street cred

Seems like it used to be my car has XX Kw, but now it's my car has XX kW, but on a low reading dyno, so its better..... pretty sad / grasping for straws if you have to mention that imo.

Dont forget about it being a hot day...

Make sure you add the mandatory and very inaccurate %15 drivetrain loss if you want a bigger number.

[Lith]

You're driving on wheels, not hubs.

You're also driving on road, not rollers which control the speed the car accelerates at. They are every bit as removed from the real world as each other. The temperature of the day doesn't matter either as the correction the dyno software uses will attempt to adjust the power/torque curves to match what they would on a "control" atmospheric situation type day.

Some dodgy (or useless) operators will put their temp sensor in a really hot place and make the resulting figure real high, there are plenty of rolling road dynos around even in NZ which as run by the operators read higher than some of the Dynapack hub dynos around.

[Al]

Make sure you add the mandatory and very inaccurate %15 drivetrain loss if you want a bigger number.

Nah you do what the poms do and let it run down in neutral 'calculating' the drivetrain loss

There was a mr2 turbo in the UK that the guy was claiming 380bhp from, it had a modified ct26.

It was actually 270rwhp at 1.6 bar and they calculated the roll down loss. Turns out the B in the poms BHP stands for bullshit.

[Akane]

You're driving on wheels, not hubs.

You're also driving on road, not rollers which control the speed the car accelerates at. They are every bit as removed from the real world as each other. The temperature of the day doesn't matter either as the correction the dyno software uses will attempt to adjust the power/torque curves to match what they would on a "control" atmospheric situation type day.

Some dodgy (or useless) operators will put their temp sensor in a really hot place and make the resulting figure real high, there are plenty of rolling road dynos around even in NZ which as run by the operators read higher than some of the Dynapack hub dynos around.

The roller has a set resistance / braking effect which is a constant, and from the time it takes to spin up the rollers you can work out your torque. Having wheels on the car is at least 3 steps closer to a real road if not more vs a hub dyno

Now let's not get to dodgey operators like a certain S15 in NZPC magazine claiming a factory S15 with factory injectors getting 250kw at the rear hub/wheels/IDK?

[Lith]

The roller has a set resistance / braking effect which is a constant, and from the time it takes to spin up the rollers you can work out your torque. Having wheels on the car is at least 3 steps closer to a real road if not more vs a hub dyno

Wrong... operator will set a fixed rate for the dyno to run through the rpm range on a rolling road, a retarder provides the amount of resistance required to maintain that rate and reports to the software the tractive effort required, then calculates from there. Its much if a muchness, in terms of real world likeliness.... except the hub dyno is more accurate as the control is finer and more direct due to a solid link so the tyres only serve to compromise accuracy.