Choosing dyno

Hi Guys ,

I'm about to start my own performance shop and i'm looking for a good 2WD dyno to start , i'm looking for something between 600-1000HP capacity and the cheapest but not the worst quality just a good dyno , I have destined about $20000 , i was reading about the inertia and eddy -current , and i've found both are good but eddy seems to be more accurately , also i would like it to be able to do test 1/4mile runs , also i don't know which are basic extra accesories i would need to purchase in order to be able to tune ,

please give me a hand

Thank you very much

20,000 can get you a used quality dyno but most quailty dynos new are about 30-45k for 2wd. You will want to ask yourself about what cars are you trying to tune. Inertia style Dynojet will most likely be the cheapest option. They are good for drag cars but you cant do any steady state tuning for part throttle. For part throttle you will want Dyno Dynamics, Mustang, or Mainline Dyno if you want a rolling road type. Dynapack dynos are also very good and accurate with no wheel slip issues but running automatic cars is sometimes hard or impossible to do.

You will need at least One pressure sensor for boost, etc and a Quality Wideband Unit (AFX, Motec, Autronic, etc)

I agree with Tommy, $20k is probably a little light for a new 2WD load bearing dyno but you should be able to find something worthwhile second hand.

As Tommy mentions, unless you are planning to focus solely on drag cars, I would stay away from an inertia dyno. They are cheaper but only any good for tuning at WOT. You really want a dyno with a power absorber that can perform steady state tuning.

Thank you Tommy and Andre , how much is the maximum time it is advisable to choose one used? , also what does it means WOT? , and what benefits or which advantages i can get from steady state tuning? what is the difference between inertia ? , i know how inertia dynos work and eddy current , but i'm a little confused about the steady state benefits ,

Thank you very much

I'm guessing you are asking how old is too old for a used dyno? Most dynos have a service life of 15 + years but at the same time they are serviceable so you can rebuild them if necessary.

WOT means wide open throttle. The inertia dyno is just a large roller with a fixed mass. There is no brake to apply load to it. These will only allow you to tune at full throttle - This is ok for a drag car but not much use for anything else - particularly if you are going to be tuning aftermarket standalone ECUs.

Steady state lets you set a fixed engine rpm (say 3000 rpm) and the dyno will hold this rpm constant. you can then vary the load using the throttle to map the engine completely. Watch some of our webinars to get a better idea of how this works - https://www.hpacademy.com/previous-webinars/fuel-tuning-link-g4-plus/

Just wanted to add that eddy current is one of the way to control the load on the dyno. ("absorber")

Air cooled eddy current dyno are very common in Europe. They don't support crazy HP but they do the job.

For example: (That's the kind of dyno I have acces here in France)

http://ptbbm.com/pdf/CARTEC/CARTEC_LPS_GB.pdf

With dynos like the Dynapack (hub dynos) I'm concerned with the weight they can carry. My tuning has mostly been on modified full size 4wds (road tuning landcruisers patrols etc) but I'd love to move to a dyno so my tunes can be more precise. I've looked into, and pretty much made my mind up to get, a dyno dynamics but I am interested in the Dynapack. Does anyone have any experience with these on full size 4wds? Can they hold the weight of a vehicle as heavy as a landcruiser or patrol?

I have had my Land Rover Discovery 4 on my DynaPack DAQ32, and that scales around 3000kg, without issues, there are notes on the maximum axle load capacity with the units that state that it is 1500kg per axle.

Thanks for that BlackRex, with the axle load is that 1500kg per corner meaning 6000kg all up? or is it 1500kg per end (front/rear) meaning 3000kg all up?

1500kg per end, so 3000kg all up.

Thanks BlackRex, I'll contact them and see what they would recommend.

I don't imagine you having any trouble with the dynapack on a 4WD as described. We've done plenty over the years with no trouble.

I bought a Superflow AD11 2wd dyno with load cell a few years ago. Brand new from Superflow it was 18999 usd. The dyno has been a rock star and very well built. It handles just about everything throw at it from diesel trucks to Honda's. I'm unsure if Superflow still makes the AD11. I have 2 complaints about the dyno, the handle controller isn't back lite and its a pain in the ass to see when the LCD gets cold. The other is the rollers sit low in the cradle so small tire cars you have to watch and make sure its going to clear the dyno deck.

Doing more research and come across this video https://www.youtube.com/watch?v=UZXbk3o-xHg

Can anyone who has used both types explain the discrepancy in outputs?

Hey there Andre, Is there really anything that the dynopac hub dyno does that the Mainline roller cant do?. If you were wanting to buy a 2wd dyno, is the extra expense of the dynopac justifiable. What is the ballpark costs of either setup in NZ

Cheers

Mike

Some of the advantages of each, are also their disadvantages, with the lack of inertia in a Dynapack very useful for evaluating small changes in settings, like plug gaps, electrical loads and the like, but when you are using a vehicle with a low inertia drive train (Formula Fords, F3, etc.), the lack of inertia from the dyno itself (lack of drive rollers) can make it difficult to get the engine to run nicely as the dyno can be constantly chasing the load. I have used both, and for just pure tuning, where you want to get the car on and off the dyno quickly, integrate the CAN data into the Dyno control system, then the Mainline is better, but for development work, reverse engineering of OEM systems and the like, where the car may be on the dyno for a week or so, then the Dynapack comes to the fore.

Thanks for your thoughts BlackRex

BlackRex pretty much nailed it. The two different dynos both have their own strengths and weaknesses and it's hard to pick a clear winner.

The setup time on a roller like our mainline is quicker than a dynapack which would suit a busy tuning shop. Repeatability is possibly marginally better on the dynapack as you would expect with a direct link to the hub and no chance of wheel spin - that being said, I've had no trouble with wheel spin on our mainline although I hardly feel I've stretched it yet with the low power cars we are using. The area I see the mainline having a real advantage is the CAN integration and data acquisition. This is an area that dynapack I feel are a little behind the 8 ball. The torque optimisation feature on the mainline in particular is excellent for tuning ignition timing, cam timing or basically any parameter that affects torque.

In dollar terms, last time I got a quote for a 4Wd dynapack it was around the $150k NZD mark although this is dependent on the torque capacity and options. Our mainline 2WD dyno is around the $50k NZD mark and I believe in 4WD form it ends up around $80k. Use those numbers as a guide only though. For accurate quotes I'd recommend talking to the respective companies.

In short both are excellent dynos and you wouldn't be disappointed with either. They are definitely in quite different price brackets and this will be a deciding factor for many.