The great debate Hub Dyno Vs Roller dyno. what is the real power difference?

In this video Stathi explains the difference between the hub dyno and the chassis roller dyno There has always been the misconception that the hub dyno can read up to 60kW power difference so let's break the myth.

[@scottroberts3158]

Good vid mate, when you first got the hub dyno installed you explained it that the hub isnt any better than the roller, just that the roller is more picky to how you set the car up on it, so the hub lets you do your work faster and more accurate with less variables to figure out.

[@IndependentMotorsports]

Yes that is completely spot on I should have added that to the video.

[@robertcorser4196]

Legend, you've come a long way since the backyard days. I knew you would do well at this. Keep up the videos!

[@IndependentMotorsports]

Thanks Rob it's certainly been a massive learning experience. Thanks for your support

[@lachiegrant4237]

Honest and real talk, the world needs more of it 👍

[@ThatTunerGuy]

Good video mate. I'll be honest, when I got my mainline I was in a similar situation. Thinking I needed to pull it down between the rollers. 2 years later and I've figured out the same as your demonstration haha. Better late then never. Keep it up!

[@gsd1121]

My FG G6ET went 304kw on the roller then went straight over to a Hub and went 311kw. Since then all tuning has been done on the hub.

[@nobodyspecial5026]

unfortunately you can’t drive without the drive wheels installed and the resulting inertia loss that goes with them. there are also numerous other hub vs roller dyno vids on yourube. Yet the show must go on …

[@rubberbandman2540]

keep making quality content mate love technical videos about all things tuning and performance

[@loustath1583]

Love his explanation and I’ve seen some guys strap the shit out of dynos before 😮but I prefer the hub for the tuner for more flexibility .

[@dan_cambo.chefdannn2577]

Good explanation stathi, keep up the videos 👌

[@fullboost]

Nice video Stathi.

[@IndependentMotorsports]

Thanks mate

[@kyleepworth6929]

Great video, very informative

[@jasontalty9627]

Great explanation 👍🏻

[@maccathirtythree]

I think the proof of your abilities and no-bullshit approach is evidenced through every car that rolls out the doors of your workshop mate. Good work.

[@IndependentMotorsports]

Thankyou

[@farmer3242]

Awesome video

[@ny8472]

Enjoyed that✔️👍

[@ericmiller4285]

Surely moment of inertia of the back dyno roller is included in the dyno calibration calculations. Running up on just one roller will affect power output...

[@IndependentMotorsports]

Its just a lazy roller. No calculations are done of it.

[@Richard25000]

Wrong! Look at the DD calibration file.. 2.59kgm^2 includes the drive and idler roller..

[@anthonywhelan8373]

From what I see you guys do it all right and the difference between the roller and hub is simple there’s no slip with a hub and you’re taking the tyre wheel combination out of the equation A lot of people wouldn’t think that you would get a different reading again if you were to change the wheel tyre size alone on the roller Also a lot of people forget the dyno is only a tuning tool and they all read differently it’s only there to see if you make a change and ghi up or down in power or Tourque

[@nick_captain_slow]

Great vid Stathi, thanks. With your experience with territory's what do you estimate is the driveline loss from the flywheel to the rollers. Thanks in advance.

[@IndependentMotorsports]

I would say somewhere between 18 and 20%. But that can vary between a lot of different cars The best thing to do is backwards calculate with your MPH

[@rubberbandman2540]

nice video

[@stevenkirk2563]

Dude great vid. Would turbo spool/load be even a larger diff than an na?

[@IndependentMotorsports]

If you set the dyno up right it should be no different

[@dallasstepto8409]

Be interesting to see if my ve ss makes any gains on the hub dyno... Engine Recently rebuilt bored 0.10 over pistons to match, higgins heads, 1 7/8 pacemaker extractors high flow cats 3" stainless exhaust tru track diff with 3.9s already had a custom grind cam before the work was carried out. Made 330.6kw on roller dyno. I was expecting atleast 350kw so wasn't impressed when it only made 330kw

[@IndependentMotorsports]

Best thing to do is speak to your tuner in regards to the power output. We prefer to do all our work on the hub dyno it just takes out the guesswork when it comes to having the right amount of grip. The Roller Dyno can be very misleading if not used correctly.

[@dallasstepto8409]

@IndependentMotorsports They have said that's around the the power they expected to see and they are a reputable business who know the ls engines well but I'd like to see if there is any difference for my car with a different tuner who also specialises in ls engines and his hub dyno.

[@juliangagliardi1367]

Great info mate, my experience as an owner of a dd chassis dyno is very similar .

[@coarsegrind]

Is the position of the tire in the same position on a single roller dyno?

[@IndependentMotorsports]

Would be close.

[@TorqueupAu]

You still using the HP Ipaq for your chassis dyno control?

[@IndependentMotorsports]

Sure am

[@Unpluggeddiagandprogramming]

Do you guys tune with hp or Diablo? And do you offer email tunes?

[@IndependentMotorsports]

Really depends on the car.we do offer mail order tunes for some cars depending on the modifications.

[@Unpluggeddiagandprogramming]

@@IndependentMotorsports my cammed jeep lol 😂

[@IndependentMotorsports]

@@Unpluggeddiagandprogramming i will be using HP where are you located?

[@Unpluggeddiagandprogramming]

@@IndependentMotorsports I’m located in the United States

[@IndependentMotorsports]

@@Unpluggeddiagandprogramming a little bit too far away.

[@kelvinleong915]

I been dyno on roller 370HP once go to hub back to 340

[@seanb250]

Great info 👍 makes perfect sense to load up the roller attached to the retarder.

[@IndependentMotorsports]

It amazes me at how many dyno operators out there do not understand the simple mechanics of the dyno.

[@martinlund9524]

The thing i see what is wrong here is that the hood / bonnet is open. The car is not running it with it open when you drive it! So why is it even open? If you make a few pulls the heat will stay longer. This is MORE of a true reading with hp/nm and what a tune can be done. Get a few extra sensorns on the car to get what the temperature is and make a tune after that. If not the dyno papper is worth nothing. Just a fancy number that is a BIG lie! A real dyno session is where you show every numbers on that the temperature is outside. The humidity. where you are located country / town /place . smoothness, SAE. what dyno you are using. closed bonnet Tyres can also be a big factor and what wheels size you are using. It is even easy to calculate if the papper is modified with math (for the most times) a Dyno is just a way to show how much Nm there is the HP is just calculated from that point. If you change what wheels you are using. or if there is 5 big persons in the car the papper is also worthless from that point of view. A Hub dyno is more easy to use to get a more accurate reading. But you are missing that you don´t have 2-4 wheels that can be a big heavy also. every thing that is needed to be rotated and moved to get the car from point A to B is something that steal power. there is a known factor that a car that is on a dyno in a town and then later far away dyno again the reading can be way off.

[@Cobra427Veight]

And turning the rear free rollers would just be wasting horse power .

[@Richard25000]

No no no!!! You're roller climbing, so knock 20kw off of that figure.. The total inertia number for dyno dynamics includes both the drive and idler roller. You're inflating your figures the moment you lose contact with the idler roller as the dyno doesnt know its now driving less inertia. Regardless whether the traction is better its not how the calculations in the software works..

[@IndependentMotorsports]

Ok but that is not the case, The front roller does all the work.