What dyno to choose MainLine vs Dynapack

Good morning to everyone .

I've been searching a lot on internet looking on both sides what have to offer , and i am a bit confused i must say this is why i make this post that maybe can help me choose ...

I own a small motor-sport shop company. At first i had a 4x4 Bapro dyno (Italian Company) that worked well at low power /normal car situation , but i was struggling to make accurate measurements or even get proper data-logging on high power (motor-sport cars) , so i decided to sell this one and buy the new HUB-Dyno Rotronics has to offer (French Company), The dyno is good with a decent Data-logging same for low or high power cars, BUT Unfortunately i had so many problems with this dyno (Which unfortunately i cannot mention here as i have a court agreement (yes this went badly for like 6 months back and fort with lawyer and experts pfff) , so the company got the dyno back and i got my money back ..

For the 3rd time now (and hopefully the last) i'm searching my "new" dyno ..

So I'm in "between" these 2 leader brands , Dynapack / Mainline for the moment i do not "care" if it is a Hub or a Roller dyno (well if i buy the Dynapack it has to be a Hub-dyno)..

I'm looking advice from guys that already owned a Dynapack or Mainline and see from their perspective what is "good" and what is "bad" with their dyno (it has to be some "bad" / downsides with every dyno nothing is Perfect ... )

For example i know that Dynapack it has an issue with Automatic cars not every automatic gearbox it can run on, On the other hand no such issue with Mainline (hub dyno) the rollers doesn't have such issue ..

A small preview on my company so you can have an idea on what i'm searching on. I work on Motor-sport car (Classic 24Lemans Cars / Formula 1 80s / prototypes / rally / time attack cars) I'm also tuning some "daily driven" cars (Vw group cars / Mercedes / Bmw ).

The dyno i will need it has to absorb something like 1200-1500hp (more is useless to me) but to have good repeatability and a very RICH data-logging ..

Sorry for the long post , Looking forward to you reply.

Regards

Christos

The fact that you've said you may need to support 1200-1500 hp may end up excluding the dynapack so this may make your choice very simple. First of all though you do need to understand that neither dyno really has a horsepower limit but rather a torque limit, so the ultimate limit on either dyno will depend on the engine torque and the final drive/gear ratio. On my old dynapack 8000 (4 x 4000 nm hub units) the most I could support was about 1000-1100 whp in 2wd but this required a final drive change to get there so it was a lot of hassle. They are problematic with some auto transmissions but to be honest most of the time they're absolutely fine. The issue normally comes up with a drag car that uses a high stall convertor where the torque multiplication is massive.

Since I had my dynapack they have released a larger 'DAQ5' unit that supports 4500 nm so that may be enough to get you across the line but you just need to understand how that torque limit will affect the cars you're tuning. Along with the max torque rating there is also a hub speed limit so you need to balance the two with overall gearing so it might not be as simple as it looks on paper.

As a product the dynapack is excellent and the hydraulic control is accurate and very fast (definitely faster than an eddy current absorber). Repeatability is also excellent and a demo I used to run on our customer nights was to run a car in steady state and turn the head lights on and off - the dyno could show the almost insignificant difference due to the alternator draw on the engine. The software is relatively user friendly but much more simplistic than what can be done with the Mainline, particularly in regard to the CAN capability on the Mainline. Despite dynapack literally being 5 km from my old workshop in Wellington, I found them remarkably difficult to deal with and this is a continual complaint I hear from other dynapack owners. At the time that I owned my dyno they also didn't seem interested in further development (we had been asking them about more advanced logging and analysis options for years which seemed to fall on deaf ears). I haven't really followed what they've done since I moved on so can't comment on the current capabilities.

The Mainline roller which we've had now for the last 4 years is excellent and the software capability is almost limitless. I will say that the user interface is written by an engineer and can be a little intimidating as there are so many options, however it doesn't take long to learn. As mentioned above, the eddy current power absorbers are a little slower than the hydraulics of the dynapack and ultimately I tend to see slightly more run to run variation on the roller than my old dp hub dyno. Mainline's customer service is absolutely out standing and Todd and Craig will bend over backwards to help any mainline dyno owner.

We've just taken delivery of our new mainline prohub 4WD dyno which I'm expecting will help with consistency as it eliminates the tyre contact patch on the roller. This is the smallest of their hub dynos yet has already been proven to support over 2500 hp in 2wd form so it would be more than up to your requirements. As a bonus last time I checked, the Mainline was quite a bit cheaper than the dynapack.

Ultimately both are excellent dynos and the biggest choice for you will be torque/power handling if you decide to go dynapack.

Thanks a lot for the answer here Andre , it was exactly what I was looking for to hear from someone how probably they owned one or the other Dyno both in your case :)

In my understanding I have to use those 2 dyno before I decide on which one I will get .. Before I buy something that will not fit my needs...

Thanks

Christos

It's a big investment so it's always advisable to test drive the machine before you make your decision, even if that may involve some cost to travel.

Andre, now that you have had some seat time with your new ProHub dyno, can you provide some feedback as to how it compares to a DynaPack ?

To elaborate on my previous post, I’m looking to buy hub dyno, and am teetering between the ProHub and a DynaPack. I’ve tuned many cars on DynaPacks and prefer them to any other chassis dyno I’ve used but have never used a ProHub as they are fairly scarce here in southern California. So:

1. Smoothness : have you found that there is any advantage to the Mainline in regards to rolling smoothness ? With the DynaPack, even when you have made every attempt to center the hubs, some cars just bounce a bit. I thought that the Mainline CV setup may help ? Also, is the amount of work to bolt up a car about the same as compared to a DynaPack ?

2. RPM stability with engines that have very low inertia : I found that on some engines with low inertia, the DynaPack had a very hard time controlling RPM.

3. Target rpm when tuning : with the DynaPack, you can just type in the exact RPM and drive up to that set point. From what I can tell the ProHub software requires you to enter a wheel RPM. If this is true, do you keep a spread sheet handy to do the math, or possibly I’m misunderstanding how the Mainline works? How do you find it for mapping when having to target non-standard rpm break points, i.e. 2716 , 4639 , 5113 rpm, etc. ?

4. Engine cooling fan : do you have the Mainline fan, and would you recommend it ?

Thank you for your time, any other thoughts or insights into your experience with the Mainline ProHub would be greatly appreciated.

Hi Chris,

First up I'd say that both are excellent dynos and both will do a good job. There are understandably pros and cons with each. To answer your specific questions:

1. I don't think there's an advantage as such to the pro hub in terms of smoothness. This really all comes down to the adaptors being bolted on concentric to the hubs and if they aren't then either dyno will give you an uncomfortable experience. A nice feature with the pro hub is that they provide adaptors with a specific stud pattern (say 5 x 114.3) which means there's no fiddly washers to align and you're guaranteed the adaptor will be concentric. Of course mainline also offer the universal adaptors too. The work required is slightly higher on the mainline as the adpators are two piece - first you bolt the adaptor to the car and then the hub unit bolts to the adaptor.

2. The prohub probably has an advantage in terms of low intertia engines due to the additional inertia of the edddy current power absorbers themselves. That being said, I haven't as yet run a car with very low inertia so can't give you first hand feedback. What I would say is that the inertia of the pro hub allows you to test gear change cuts which is almost impossible on a dp.

3. The prohub set points are related to axle rpm but it's not a big deal since the engine speed relating to the axle speed is also shown. Not perhaps as simple as dp but certainly not a problem. You can control the hub rpm very finely so there's no trouble with odd break points

4. Yes we have the mainline fan and it's effective and well packaged. I still find that it can be insufficient for sustained high rpm/load steady state tuning but there'd be few fans that would cope better I'd think.

I will add that the mainline software is initially a little daunting and less intuitive than dp. You learn your way around very quickly though and the advantage is that it's incredibly powerful. I don't know what dp have done in the 6 years since I sold my business but over the 12-13 years I owned two dp dynos I was constantly frustrated by the lack of software features, particularly around data acquisition. The Mainline is insanely powerful in this regard, particularly if you have the CAN option to take the ECU data stream.

Lastly customer service at dynapack was terrible when I dealt with them. My shop was literally around the corner from dp's factory yet I get faster responses and better service now from Mainline who are in a different country. I found that there was a certain arrogance expressed by dynapack about their product and it felt like they were grudgingly doing you a favour allowing you to buy one. This sentiment has been echoed by the majority of dp owners I've met world wide. I believe that dp sold dynos in spite of their best efforts to the contrary and they were only successful because at the time they happened to have the best product. That however has changed and now products like the mainline do everything the dp can do and more. Mainline have fallen over backwards to help us out any time we have a question or a problem which is refreshing. I hear this from other mainline owners all around the world so it's not just because of our brand.

I'll add a caveat here: I haven't owned or used a dp dyno for 6 years now and I know they have new software and I believe thy've worked on improving their DAQ system including CAN and OBD2 comms. I have can't speak for these features because I haven't used them myself. Their customer service may also have turned a corner in the time I've been with mainline. I can only speak for my own experiences.

A couple of other factors to consider. If you're considering tuning high power engines then the prohub is 100% the right choice. The dp is torque limited and my old unit would shut down above about 4400 nm. That might sound like a lot, however once you factor in the gearing and final drive, this can be problematic with engines producing 1000-1200 hp in 2wd form. It's made worse if you have an auto trans and torque converter. For comparison even the smallest pro hub dyno will handle in the vicinity of double the torque of the largest dp dyno.

Due to the inertia inherent in the eddy current absorber there is a little more latency in control with the prohub compared to the hydraulic control of the dp. I'm splitting hairs but it's worth mentioning, particularly if you're already familiar with dp. Lastly, the pro hub pods are significantly larger and heavier than the dp pods. This may be an issue if you're limited on space.

How did this progress, what did you end up buying?

Mainline controlling DynaPack absorbers would be the best option.

So just following up here, based on Andres previous post and discussions with others that owned Mainline dynos, I did go ahead and purchase a ProHub 2000, and received it late 2020. After using it for about two years now I can provide some feedback in case it is useful to anyone else.

1.Smoothness : a majority of the cars I test use a 6 x 114.3 lug bolt pattern, as Andre mentioned the Mainline comes with your choice of three specific bolt patterns. In addition, these adapters are slotted and have special washers similar to that of the Dynapack adapters, so you can use them on other bolt patterns. With the Dynapack I always had to use a custom made six lug to five lug adapter on top of the Dynapack adapter as they do not offer a six lug adapter. Now that I have these specific “hats” from Mainline, I have found that it significantly reduces the setup time to get the car on they dyno. I think overall that the dyno to vehicle design on the Mainline is easier to use than that of the Dynapack. More importantly, overall I just find less runout issues with the Mainline, most vehicles have very little if any bounce when running on the ProHub. Other advantages I have found of the ProHub pod design:

a. Longer reach of the dyno which is needed with cars that have narrowed rear ends or wide fenders.

b. Clearance for exhaust ducting for cars with side exhaust (see photos.)

c. Allows for opening and closing of doors.

The only disadvantage I’ve found of the ProHub pod design is the physical size of the units, they do take up a bit more width when installed than the Dynapack. Also you have to be mindful not to run over the control cables that go to the dyno pods as they will crush unlike the Dynapacks.

2. RPM stability : as Simon noted, the ProHub does seem to have an advantage on low inertia engines as I have been able to dyno, without trouble, midgets and lightning sprints. This was not possible on the Dynapack as when we tried we would get big swings in rpm control.

I’ve found that added inertia of the ProHub has an additional benefit, it’s much easier to tune very low load areas, and because there is some inertia you can also test overrun. For comparison, on a Dynapack if you de-clutch from lets say 60 mph, the drivetrain will stop almost immediately, where with the ProHub the drivetrain will coast down. Not nearly as much inertia as a roller dyno but still enough to be useful.

3. RPM setpoints : I agree with Simon, using the pg˄ and pg˅ is no big deal, especially since you can control the rate of increase/decrease by holding the shift or Ctrl keys in combination with pg˄ and pg˅. That said I really did like the ability to just type in the rpm on the Dynapack. There is really no difference I have found in the ability of either dyno to hold the rpm constant.

4. Dyno fan : This is certainly one of the better features of this dyno and besides the power capacity of the dyno was one of the reasons I decided to buy it. After using many different chassis dynos over the years, I have found that most dyno shops don’t have adequate fan setups. A typical carpet dryer fan or two may help cool down the car with it not running or idling but won’t do much for any sort of steady state tuning especially with any higher HP cars. When I went to order the dyno, Mainline had switched to a axial type blower which although still decent was not as powerful and the centrifugal blower they had previously offered. After speaking with Todd at Mainline I found out that the issue was difficult for them to source electric motors there in Australia that would work with US spec power. I was able to order the centrifugal blower without the 10HP motor, however Mainline supplied all of the other needed parts such as belts and pulleys. I simply ordered and installed a 3ph 10HP motor from a US supplier. Although it may not be as effective as driving down the road at 100mph it does a better job of any thing I’ve used on other chassis dynos. In addition, you can turn it off and on with a tap of the V key or set it to turn on and off under certain hub speeds.

Other points :

In regards to the software I would completely agree with Andre, there is a bit more there to learn with the Mainline software than what you have with the Dynapack. Although Mainline does give you a manual it does not cover in detail all the different features of their software. I suspect this is because they are always adding new features to the software based on customer requests. Not really a problem as Todd at Mainline has always provided excellent supportand I would say is quite clear that he takes a lot of pride in his product.

When I used to routinely operate a Dynapack dyno, I always had good support from the US reps located in Fresno. I did have a few opportunities to communicate directly with the factory in NZ and I have to say they were not the friendliest so I can understand Andres perspective on this topic.

Even the smallest ProHub, the 2000 model, has considerably higher torque capacity than the Dynapack. Unlike the Dynapack, if you exceed the torque capacity of the ProHub, the dyno will drift, not stop and flash a red warning on the screen and then proceed to shut down the PC.

One other thing I really like about the ProHub which I don’t often see mentioned is that it is air cooled, no water hoses are required unlike the Dynapack. Although I was a little concerned about the cooling capacity before buying the dyno I have yet to run into dyno overheating issues using the ProHub, even while steady state tuning for extended periods of time on fairly high hp cars.

Both the secondary tach pickup and the primary/low voltage rpm pick work as well if not better than any other dyno I've used. If you have ever fought with trying to get a good rpm signal you will know how important this is.

There were a few things I did not know or understand about the Mainline ProHub before I purchased and started using it. In retrospect, these points would have been obvious if I had actually been able to use the dyno before buying it.

1. It does not handle data in the same way as other dyno’s such as the Dynapack or even a Dynojet. As explained by Mainline, it records data in 25 axle rpm data-point “buckets”. That is, it averages data at those intervals similarly to how a SuperFlow engine dyno does on a power sweep. With this you don’t get all of the nuances as you would lets say with a Dynapack and the actual engine rpm points typically range from about 75 to 125 rpm. That said, the power measurements are very consistent run to run assuming you keep consistent the running variables such as engine air and coolant temperature.

2. Even though you can use calculated or measured engine speed on the X axis, everything is based off of axle rpm, so you can’t compare vehicles easily that have different gear ratios. My work around in these situations has been to export the runs into .csv files and then plot them in a piece of software called UniPlot. Certainly not a deal breaker but I would say it is the one thing I would most like to see changed on this dyno. In any case, UniPlot allows you to configure the graphs however you want as well you can import from multiple data sources so for example you could plot both data from the ecu and from the dyno in the same graph set.

3. Hub speed measurements are converted into an analog voltage that is measured and interpreted by the dyno controller. I not being scientific here, but it seems to me that there is a little loss of precision doing it this way as compared to the Dynapack.

In closing I would say that overall I’m very happy with this dyno and after using it for two years I believe this is still the best choice for the work that I am doing.

- Chris

Chris -- a very helpful post. Thanks for the details about the Mainline ProHub.

Wow Chris, super detailed post. Thank you very much for taking the time to write this!