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Craig Torrens - March 2nd, 2004 at 05:18 PM

Dyno Sheet

[Edited on 2-3-2004 by Craig Torrens]


MickH - March 2nd, 2004 at 07:00 PM

!!!!!!!!:D


wibble - March 3rd, 2004 at 10:45 AM

is that rear wheel or flywheel??


HotRodMatt - March 3rd, 2004 at 11:15 AM

At the wheels.


56astro - March 3rd, 2004 at 01:02 PM

Quote:
Originally posted by wibble
is that rear wheel or flywheel??


I love that sort of talk!

:cool:


Gracey - March 3rd, 2004 at 02:06 PM

Thanks Craig, I was just about to ask you if you had it yet.:D
I must say that looks like a Honda torque curve...........very flat:thumb:thumb


Andrew Grace


Cam - March 4th, 2004 at 08:35 AM

AMG beat you all :P


56astro - June 29th, 2004 at 05:56 PM

where has the dyno sheet gone??


Desert Moose - June 29th, 2004 at 06:49 PM

Quote:
Originally posted by 56astro
where has the dyno sheet gone??


What this one ......lol
http://img78.photobucket.com/albums/v252/Moose906/untitled.bmp


Alex Holzl - June 29th, 2004 at 06:51 PM

gotta bigga one


Desert Moose - June 29th, 2004 at 07:04 PM

I will try again................ yes its bigger but it fuzzy :cry


pete wood - June 29th, 2004 at 08:31 PM

So what does craig's slip look like?
Doesn't show up on my puter screen :(


fullnoise - June 30th, 2004 at 08:49 AM

Deja vu. I have a headache.:cry


gayanne - June 30th, 2004 at 09:11 AM


MickH - June 30th, 2004 at 09:35 AM

You will lose power through the gearbox. If the engine had 200hp at the flywheel it would not have the same at the rear wheels.


Gracey - June 30th, 2004 at 12:17 PM

Even motorcycles experience HP loss through their drivetrain and they one of the most efficient. Around 5% for chain and sprockets.


HotRodMatt - June 30th, 2004 at 12:24 PM

All gearboxes reduce HP.

Just need to look at all the work that Dyno Dynamics have done testing hundreds of engine/trans so that their chassis dynos can provide a calculated back to the flywheel figure if desired.

Even the direct drive of a Top Fueler looses HP through the clutch.


AdrianH - June 30th, 2004 at 05:04 PM

Work on about 15% loss, so 121@wheels = 140@the fly...

Think about that 80 weight oil being squeezed outta teeth, theres a reason it gets hot... friction


gayanne - June 30th, 2004 at 07:24 PM

Lots of expert opinions and all constructive,it still comes down to diff ratios working threw Gboxes and tyres.Percentage Hp for rear engines is 5% to10% this info comes from Goodman Race Engines ,gives us somthing to think about when doing Dyno runs to Track runs.JVLRacing[/size]

[Edited on 30-6-2004 by gayanne]


Desert Moose - June 30th, 2004 at 11:58 PM

Quote:
Originally posted by Craig Torrens
Quote:
Originally posted by gayanne



What drugs are you on !!!

And NO, Stan would not agree.

And if Goodman engines think that you only loose 1% of your horsepower through a gearbox well........................


I want Goodman to build me a transaxle. yahoo only 1%


humpty - July 1st, 2004 at 12:17 AM

Any spec on the Pobjoy donk or are we liven a dream?

As for loosing power through the trans...Gene Berg told me 15 years ago that you can expect around 15% loss, minimum.

My little 1776 made a best quarter of 14.8 and no special trans ratios....
So what can I expect for HP.
Never dyno'd it, may have to some day!
Keep in mind my engine is now over 10 years old!

[Edited on 30-6-2004 by humpty]


seagull - July 1st, 2004 at 12:30 AM

Simon may be perth should have a vw dyno day ??


humpty - July 1st, 2004 at 12:46 AM

I know Myaree Dyno tune have dyno days from time to time. Everyone turns up, big blocks to cosworths....Be nice to see a certain red Notch there!, Maybe my bug too!


Desert Moose - July 1st, 2004 at 02:27 AM

Quote:
Originally posted by seagull
Simon may be perth should have a vw dyno day ??


What a top idea !!! who in perth has a Dyno Dynamics dyno..:thumb



[Edited on 30-6-2004 by Desert Moose]


Peter Leonard - July 1st, 2004 at 08:13 AM

humpty, first we need to know what the car weighed.


gayanne - July 1st, 2004 at 08:31 AM

Quote:
Originally posted by Craig Torrens
Quote:
Originally posted by gayanne



What drugs are you on !!!

And NO, Stan would not agree.

And if Goodman engines think that you only loose 1% of your horsepower through a gearbox well........................


AdrianH - July 1st, 2004 at 09:58 AM

Not trying to start a shit fight, but is it possible to have a look at the specs on a Pobjoy ? Cam ? compression ? etc... or do you have to sign a confidentiality agreement or something before buying one??

Ive picked up little tidbits of info, looking for some substance !!!


Craig Paton - July 1st, 2004 at 01:12 PM

Me to Adrian!!
These Dynamic Dyno's do they take into account horsepower sapping high altitude??

Craig P.:bounce


Baja Wes - July 1st, 2004 at 01:17 PM

RE: gearbox losses.

as others have said, use 15% as a minimum.

Most dyno operators will use about 17%. This is right for most modern vehicles, and mainly front wheel drives. FWD cars has efficient gearboxes as each gearset is parallel to the next.

VW's are older designs, and has a ring and pinion, which is not very efficient. Kombi gearboxes are less efficent than beetle gearboxes. VW gearbox'es seem to be losing somewhere between 20 and 25%.

It the helical gears that suck the power. The helix angle forces some of the torque to be transmitted, and some of it to be wasted in a thrust force.

This is why race cars use striaght cut gears in their gearboxes. They don't have the inefficency problems of helical gears.

Motorcycles almost always use straight cut gears, that is why they are much more efficient.


gayanne - July 1st, 2004 at 02:02 PM

Quote:
Originally posted by Baja Wes
RE: gearbox losses.

as others have said, use 15% as a minimum.

Most dyno operators will use about 17%. This is right for most modern vehicles, and mainly front wheel drives. FWD cars has efficient gearboxes as each gearset is parallel to the next.

VW's are older designs, and has a ring and pinion, which is not very efficient. Kombi gearboxes are less efficent than beetle gearboxes. VW gearbox'es seem to be losing somewhere between 20 and 25%.

It the helical gears that suck the power. The helix angle forces some of the torque to be transmitted, and some of it to be wasted in a thrust force.

This is why race cars use striaght cut gears in their gearboxes. They don't have the inefficency problems of helical gears.

Motorcycles almost always use straight cut gears, that is why they are much more efficient.
Text[size=1]Well said baja wes you have done your homework top stuff and i should of explained myselfbetter.Talking Racecars to standard cars is a lot different.Thanks JVLRacing[/size]