Link g4+ thunder vs Motec M1

Hi Andre/everyone

Just wanting some advice on which ecu to choose, obviously the age old answer of picking the ecu to suit my tuner doesn't apply as i am the tuner and can learn to tune any platform i need to within these courses.

I am asking for an expert opinion based on experiences i haven't had yet and don't want to invest money into the wrong product.

Basically I'm stuck deciding between a link g4 thunder or motec m1 with the gpr package? Don't really understand these packages with the motec yet but feel free to correct me.

On my time attack supra i plan to run the following (besides the obvious/standard)

-infared tyre temp sensors

-sequential gearbox, strain gauge for ignition cut and blip down shift

-8 position rotary switch for starting launch rpm or 8 different launch strategies (boost/rpm)

-8 position rotary switch with multiple boost levels in small increments

Quite simple really i just haven't seen those abilities in the link software but im sure there are ways around that?

I want to use this vehicle for many different racing types hence wanting launch and boost levels to be very flexible, i know it will take ages to setup but that's fine..

Thanks

M.Bird

Ive used both products extensively and unsurprisingly each has pros and cons. Essentially either product will actually cover all of the requirements you list with relative ease so you probably need to look a bit deeper to make up your mind.

Here's my thoughts:

For those users who aren't familiar with the M1 platform, it can feel quite restrictive initially. For example you can't go ahead and set up an auxiliary output and utilise any channels as axis to operate that output. This has been a concern for many Motec tuners who have come from the Mx00 platform. That being said on the current release of GPR there isn't a lot of main stream functionality that you couldn't incorporate.

Right now I'd say that the gear cut control functionality in the M1 is superior to the Link G4+ but it's also more time consuming and complex to setup. The traction control functionality in the M1 (you didn't mention traction control but I'll assume you may want to use it) is also superior to the Link G4+ and in this case is actually quite simple to get your head around and setup. It's without a doubt the most effective traction control system I've used in an aftermarket ECU to date. Lastly closed loop boost control on the M1 is also better - There is an issue with the closed loop boost control in the Link G4 firmware that we've brought to Link's attention but right now it still isn't fixed. Basically I find it impossible to get accurate and stable closed loop control on the Link G4+ and always revert to my 'passive open loop' strategy. The boost control on our 86 is typically within 1 kPa of target on the M1 and is the best I've experienced to date.

Cost is another consideration as the Thunder is likely to end up cheaper than the M1 and it also includes dual onboard lambda control. With the M1 you'll need to factor in the cost for a Motec LTC (lambda to CAN) if you want onboard lambda.

As far as IR temp sensors for tire temp go, the M1 with a GPR package won't allow you to read these directly into the ECU (unless you buy a development licence in which case you can pretty much make the ECU do whatever you wish if you're able to write the code). The G4+ doesn't have pre-configured inputs for tire temp via CAN, however you could bring these in as ANV channels over CAN so you can view and log them in the ECU.

The reality in most cases is regardless of the ECU you'll probably be using a dash logger too and in this case you can use this for the majority of your logging. As far as the dash goes I'd strongly recommend the Motec range (CDL3 or C125 for example) regardless which ECU you choose. It will happily talk to any ECU via CAN and you can then bring your tire temps in to the dash and log them there (as well as any other CAN-based products). The main reason I'm a very vocal advocate for Motec's dashes is because their i2 data analysis package is so powerful.

I'm looking forward to seeing how this discussion goes :)

Thank you Andre for your reply, i knew you would be the exact person to give me the right feedback on my decision making.

So far with your reply i would be happy to spend the extra money on the motec as im sure there would be other advantages aswell that I'm sure i will learn in the motec m1 walk-through course.

Also in my opinion motec has a huge list of addons (yeh they might be expensive) that should more or less be plug and play that i haven't seen elsewhere.

Would you be able to chime in on other pros and cons of the motec m1 gpr package that you have used (or think is neccesary) for a world time attack level car

Ive never built a car to such a high standard but that's the aim for this vehicle as my own personal r&d project.

Thanks again for the support and i will say to any readers that the link is a fantastic product and they are my first choice usually but im thinking there's a need to step up to the motec range for this vehicle

+1 for the Motec CDL3 dash, unbelievably configurable, light and with the free data logging and IO licences now remarkably good value (just a shame I bought mine BEFORE!).

On the subject of the Motec M1, if you want something from a GP package that is a fairly common requirement then ask Motec for it. If enough people would be interested (ie they could sell more units to cover the development costs) they will probably add it in a future release (for example, digital output throttle sensors, which allowed me to buy the cheaper model saving several hundred pounds). Note that a new release of GP is due sometime soon, going to be interesting to see what new toys they have added!

That's a nice topic, since I'm dealing with both ECU. But to be honest I' haven't used the M1 alot yet.

Andre have you tried the link traction control before 3D table was available. Think the 3D gives some more options. I haven't found an option in M1 to tune the PID algorithm. Isn't that necessary on different cars?

Regarding gear cut. Could you explain what's better on the M1? settings look very similary on both ECU (since the big shift update from LINK). Only thing that I can think of is Paddle shift isn't really possible on the LINK.

An last, I'm really wondering what's wrong with the LINK closed loop system? Can you elaborate that more detailed please? I found it some times difficult to setup, but worked for me so far.

Generally as you mentioned the M1 can be in some points very restricted. For example no TPS vs Boost compensation mapping is possible. Don't know how i should map an RB26 for example with an M1. Of course you can write your own firmware, but that's really out of budget and time frame for most cars and customers. And furthermore something a highend should have the ability to deal with out of the box.

Please eleborate on the paddle shift and LinkECU as I've probably got that info wrong. I've always been under the Impression, that the LinkECU can switch gears with cloosed loop gear control on the press of a button (which essentially could be a paddle).

Also, yes, while I can second what Adrian mentioned about the boost control (worked out good so far), I could also probably take a guess on what Andre meant about that topic. I've found that it swings way too much above and below target once you start introducing some integral gain.

I've always been able to get it close, but I'm a very fussy person so I'd like it to be either spot on or within 1kPa, which I haven't been able to get to.

Not a problem though with open loop.

have you put Emtron KV8 in consideration ?

I'll try and cover everything :)

@houseofautomotive - In the current age we live in compatibility between products is greatly aided by CAN communication. Sure if you're dealing with products from a single manufacturer then the integration is usually smoother but it's possible to integrate a variety of products provided you have the CAN template or are able to decode it.

The GPR package is pretty complete now compared to when I first got involved with the M1 product - Back then it didn't offer staged injection, flex fuel or nitrous support. At WTAC level in the Pro Class you're quite likely to want features or functionality not supported in the GPR package (or any ECU's release firmware for that matter) - GPS based 'sectored' boost control strategies spring to mind for example. While the GPR package will do the job, you may benefit at this level from a development licence so you can add or alter functionality to suit.

@greenamex2 I really love the CDL3 in our 86. It's still expensive when you compare to something like a Racetechnology dash but for me the power of i2 easily justifies the extra expense. It's not until you try working with something like the Racepak IQ3 dash that you quickly understand where the extra dollars have gone in the development of the CDl3 (or C125 for that matter). It's horses for courses obviously and for many the feature set of the Motec dash would be overkill for their needs.

@Adrian, yes I've been using the Link traction control since it was in beta. Don't get me wrong, it's actually a really good system and works well in our 350Z (although in all honesty the Z isn't really challenged for traction most of the time). I think you kind of hit the nail on the head with your comment about PID in the M1 - there isn't any PID settings to adjust as the traction control system is an engine speed limiter that is based off un-driven wheel speed, gear and desired slip target. In my experience 99.5% of tuners struggle with effectively tuning a PID control algorithm so this presents the biggest stumbling block for tuning a PID-based traction control system. The M1 on the other hand relies on the already very effective engine speed limiter and we just decide on the allowable slip. The M1 also allows the tuner to use fuel cut, ignition cut or a combination of both as you see fit with a lot of flexibility. The only thing I'd like to see is the addition of ignition retard (which I added into my custom package). In addition it's nice that the M1 lets you use lat G and road speed as modifiers for your base slip target.

As far as the gear cut control, there is a lot more flexibility in the M1 in terms of the shift timing. With these sort of systems the devil is in the detail and the M1 just gives finer control here. That's not to say that the Link G4+ can't do a good job here - I'm just talking about levels of refinement.

The Link closed loop boost control system appears to have some bugs relating to the way the P, I and D corrections are calculated and applied. I can always get rock solid boost control using the closed loop parameters when I'm on the dyno performing ramp runs, but as soon as you introduce transient throttle application or take the car off the dyno I see the boost overshoot target. I'll add that I'm incredibly fussy with boost control and most Link dealers report no issue and are happy with the control. I've been through this at length with Link and we've also produced logs demonstrating the issue on Link's FD RX7 where I can produce an over boost of 10-12 kPa. I've just had a chat with the guys at Link to see where this is at and understand that they have re-written the boost control system and have something that's working really well now. You can expect this will filter through in an upcoming firmware release.

I've tuned several cars here in NZ that ran in boost limited race series and an over boost of 10 kPa would have you eliminated from the results. On our 86 with the M150 I can achieve boost control within 1 kPa of my target as a comparison.

Hi Adrian,

With the comment of their being no Boost Vs. TPS compensation in the M1, the Boost Aim Main table can be configured as TPS only, Engine Speed only or TPS Vs. Engine Speed, you can also base it off of Ambient Pressure, or use Ambient Pressure as a compensation in the tables.

If you mean something different to this, please let me know and I'll assist where I can.

Thanks again for the feedback on each subject andre, think i might download the tune and build software and run through the m1 course and see where I'm at after that..

I have definetly been thinking about the build package for future upgrades basically makes the ecu future proof for many years