Summary of ECU research

[WR1 Bro]

The replacement ECU's (Motec,link,Hydra,Gems,Apexi) compared to the standard ECU just have a little more control and can react quicker to different circumstances. Motec appears to be the daddy really. They should give you a bit more BHP and torque (maybe 10-15 of each). Some of them have features like dual boost maps, Anti lag, Launch control etc..Because of the quicker reactions of them you can map a little closer to the edge of detonation etc.

Also a MAF based system like o.e will only be good for maybe 450 BHP. After this you need a better ECU.

The downside of them is that some of the competition based ECU's like Gems and Link can make the car a bit obnoxious at tickover and low RPM.

[Gazman2054]

The replacement ECU's (Motec,link,Hydra,Gems,Apexi) compared to the standard ECU just have a little more control and can react quicker to different circumstances. Motec appears to be the daddy really. They should give you a bit more BHP and torque (maybe 10-15 of each). Some of them have features like dual boost maps, Anti lag, Launch control etc..Because of the quicker reactions of them you can map a little closer to the edge of detonation etc.

Also a MAF based system like o.e will only be good for maybe 450 BHP. After this you need a better ECU.

The downside of them is that some of the competition based ECU's like Gems and Link can make the car a bit obnoxious at tickover and low RPM.

Nice reserch matey

[WR1 Bro]

I like to share my technical knowledge occasionally!

[Gazman2054]

I like to share my technical knowledge occasionally!

If you were lucking to change your ECU witch would YOU go for then????

[WR1 Bro]

On the face of it, this seems like a simple question. Unfortunately not, you need to also consider who you want to do the mapping too. Maybe that could form part of my follow-up research.

[Gee Wr1]

Could tell you about GEMS as there is a car fitted with this sitting on my drive.
Also its more cold start that is the issue rather than idle.

[Gee Wr1]

Could also tell you who not to get map a gems ecu.

[marky mark]

Personally - (and talking about Subaru specific only)

If i had a gems, i would get only Steve Simpson to map it.

motec would be either Dave Rowe or Bob Rawle.

Link would be only Bob Rawle

Apexi would be Andy Forrest or possibly Paul Blamire/Simon Roe

Hydra would be Richard Bulmer.

Tek 3 of standard ECU would be either Andy Forrest or Bob Rawle.

[WR1 Bro]

Could tell you about GEMS as there is a car fitted with this sitting on my drive.
Also its more cold start that is the issue rather than idle.

Could also tell you who not to get map a gems ecu.

Feel free to share the knowledge?

[POESY]

I have motec - mapped at Owen Developments. They seem to know what they are doing. Fortunately they have a demo evo 8 race/track car which runs more or less the same spec as my car so I get the benefits of their experience, which is good.

They also run a scoob rally car, but dont know the spec on that tbh. Wouldnt be surprised if it runs motec too as that seems to be the management system they push.

Going for the motec M800 also gives you the benefit of anti-lagg and launch control, which is good. Although I leave both well and truely turned off - for now !!!

[ScoobyMania]

The replacement ECU's (Motec,link,Hydra,Gems,Apexi) compared to the standard ECU just have a little more control and can react quicker to different circumstances. Motec appears to be the daddy really. They should give you a bit more BHP and torque (maybe 10-15 of each). Some of them have features like dual boost maps, Anti lag, Launch control etc..Because of the quicker reactions of them you can map a little closer to the edge of detonation etc.

They're all quite different in their own way.
We don't use GEMS as our preferred ECU by accident. (We can do Motec and Apexi as well), but GEMS is the best all rounder available and does pretty much all the others do, and more than most, often for less.

It's (Markedly) cheaper than Motec, doesn't need a custom loom or wire chopping to fit. (GEMS drops straight into the factory ECU case, as does Sigma). Last I heard, Motec still hadn't sussed the AVCS control either?

Hydra needs its own complete loom/rewire from what I've seen of it, (but admittedly we've not looked at it in depth as we've not needed to).

Apexi doesn't have the range of control (particularly over boost) as GEMS, that's why you have to buy a secondary boost controller as well, making it more expensive than it might first appear. They also don't do past 99MY (IIRC) either.

Also a MAF based system like o.e will only be good for maybe 450 BHP. After this you need a better ECU.

You can re-scale a MAF, but it's not so straight forward, and by the time you get to that sort of reliable power, as you so rightly say, you would be wanting something more "up to the task" than any of the MAF based units are. Also, the main contender in this area is SO long winded by the way it gets mapped, to get a satisfactory job from it, you would need to spend like 20 times longer (at least) mapping as it is VERY long winded to get alterations into the ECU and even that is limited by the amount of re-flashes the eeprom can take

The downside of them is that some of the competition based ECU's like Gems and Link can make the car a bit obnoxious at tickover and low RPM.

Well, maybe 2 or so years ago, that would be accurate, but GEMS, have worked A LOT on these areas and still do, this is generated by the "road" market demanding better performance in this area; as motorsport units, they rarely see tickover (jacked open throttles & ALS). There are regular updates to GEMS ECU eeproms, each (usually) bringing software improvements to "operability". Cold start has been one of the most complex areas to master; there are (at least) 5 seperate fuel relative control maps, all interacting with each other at start-up, and you only usually get 1 go at setting up the cold start as well.

Huge subject in itself of course, and difficult to sum up so briefly. I'm sure it will generate further discussion.

[marky mark]

Nice info Scoobymania. I did not realise the motec had no AVCS control. Im sure you have been looking at the recent RR V road mapping and the sigma V apexi threads on SN with Harveys input

Im sure Bro will reply and prompt further discussion

[WR1 Bro]

Great info

As I'm sure Marky Mark knows, this is way above my level of knowledge!

[ScoobyMania]

Nice info Scoobymania. I did not realise the motec had no AVCS control. Im sure you have been looking at the recent RR V road mapping and the sigma V apexi threads on SN with Harveys input

Im sure Bro will reply and prompt further discussion

Yes I have seen that thread, it's both mildly amusing, and a little worrying at the same time.

The people who actually know anything about mapping and interpretation of results (on that thread) fall into 2 camps.

The ones who know, but are arguing that road mapping is the best are the most dangerous (and in my opinion) the most malicious.
They are leading the 'innocent' into believing that "real world" mapping is the way to go and that can only be deliberate (where ignorant by choice also equates to deliberate). It's being done by the people who don't have one.... whether it be because they can't afford one or because the amount and level of mapping they do doesn't warrant one (and consequently they can't afford one).

The second camp is the ones who know that a RR plays an invaluable role in mapping of cars. little more needs to be said there. We've moved with natural progression from simple road mapping, to dyno AND road mapping.

Certainly, the big HP cars we are routinely involved in, you simply couldn't get them right without a dyno. It's pointless me re-kindling the points within that thread and it's why we haven't commented in there.

There are a "band of followers" in the road only mappers camps that it's simply pointless trying to educate (and I don't mean that in a condescending way). They have their 'favourites' and it's pointless trying to "taint" there opinions of them by getting into an argument.

We don't have our own rolling road, and could get cars mapped "cheaper" and still leave customers impressed with what we do. Our work is more thorough than that though which is the sole reason we do it the right way, not just the easy way.


There are a myriad of circumstances and factors that are impossible to miss with just road mapping, that we see on the RR when we go to map a car, it's a fantastic diagnostic tool (in the right hands) as well. Remember, though, it's only a "tool", and needs skilled hands to get the best out of it.

[marky mark]

Great info

As I'm sure Marky Mark knows, this is way above my level of knowledge!

Im not so sure, You seem to be ploughing your own furrow nicely investigating your future tuning options

If as Scoobymania says is true (and i have no reason to disbelieve) in that Gems have done a lot of work on the low down running and cold starting in the last couple of years then fair play. The last Gems equipped car i drove (not sure who mapped it though) Was a little obnoxious low down and at tickover.

The 5 or so Motec equipped cars i have driven or been in (including Chris B's) have ran as though they have a o.e ECU still.

Scoobymania - have you come across the sigma ECU yet? your thoughts (with your salesmans hat off )

Poesy - Is each FQ400 individually mapped at Owen, or is it a generic map they just download after initial development into each car?

[marky mark]

I was going to post on the thread in question with my own experience, but once the nastiness started thought better of it.

Not withstanding the complications and issues of mapping a big BHP car on the road and the obvious vested interest of some of the people posting on that thread, i think its plain to see that a) A RR is going to take a lot of time off the job b) it needs to be at least checked on the road.

My car has always been mapped by Bob Rawle. At a RR day at G force shortly after it was mapped following a power hike, It was shown that i had a big hole midrange that the car never efectively recovered from and lopped maybe 25 BHP off all the way from 4500 up.

I could not really feel this on the road, and Bob did not notice it either. He was sat in the car on the rollers at the time and its fair to say he felt rather embarrased.

Bit of AFR tweekery and a slight adjustment to the maf scaling and a couple of weeks later on the same rollers it gave the curves it has now.

So certainly in my case, it would probably have saved time if it had been on the rollers first for mapping. And if i had not put it on the rollers at a RR day it may well still be underperforming now.

[ScoobyMania]

Scoobymania - have you come across the sigma ECU yet? your thoughts (with your salesmans hat off )

Well...... "sales hat", I'm not sure I ever got issued one of those or not? I'd like to think we sort the right products out first, and know them well, thereafter they pretty much sell themselves?
So, yes we have been aware of it for several years. Due to its origins, we've been pushing its development for some considerable time as with the right guidance, it will be a very good piece of kit. The earlier cars (up to 98MY I think) units are already out working.

Our "demonstrator" (STi7 base car) is being used for development of it as well, (it will be running 8 injectors) and we can more carefully evlauate and monitor what its doing and how.

To sum up, it IS a good ECU and will be developed further. Resistance to it "in the open community" centres more around other peoples alliances to alternate products than anything else, which will be their loss overall. As a "product" it's as good as some and better than the remaining options.

[ScoobyMania]

I was going to post on the thread in question with my own experience, but once the nastiness started thought better of it.

Not withstanding the complications and issues of mapping a big BHP car on the road and the obvious vested interest of some of the people posting on that thread, i think its plain to see that a) A RR is going to take a lot of time off the job b) it needs to be at least checked on the road.

Yes, agree entirely. We're not interested in mudfights over this stuff. As an active member on SN since pre 1999 though, the machinations of some very prominant posters are little short of outright deception! Not only by themselves, but often due to their misguided (and overtly aggressive/adversariel) band of followers.

My car has always been mapped by Bob Rawle. At a RR day at G force shortly after it was mapped following a power hike, It was shown that i had a big hole midrange that the car never efectively recovered from and lopped maybe 25 BHP off all the way from 4500 up.

I could not really feel this on the road, and Bob did not notice it either. He was sat in the car on the rollers at the time and its fair to say he felt rather embarrased.

Bit of AFR tweekery and a slight adjustment to the maf scaling and a couple of weeks later on the same rollers it gave the curves it has now.

So certainly in my case, it would probably have saved time if it had been on the rollers first for mapping. And if i had not put it on the rollers at a RR day it may well still be underperforming now.

And I think that it's unfortunate that you can't tell that on SN, (and would also concur that it would have done more harm than good to post it).

I will comment that I (Mike) think Bob is a fantastic bloke, and on the whole, more than just competent....... The difference though is that he is from the parts I have read of that thread, one of the predominantly "pro-road" camp. A good portion of some 'others' with some mapping knowledge in that thread have considerably less knowledge than Bob!
However, your own experiences accurately encapsulate the whole answer to the question running in that thread, totally and completely.

[POESY]

Poesy - Is each FQ400 individually mapped at Owen, or is it a generic map they just download after initial development into each car?

I believe its a generic map when you origionally buy the car, but ive been back to them twice since to have the car checked over (every 8 - 10 months or so) and each time they tell me theyve "refined" it a little further. Not sure what that means exactly but it always goes well when I get it back.

[marky mark]

Cheers Poesy. Thats good service

Scoobymania - im not interested in the mudfight either - and bearing in mind individual customers have already been dragged into it is why i dont want to post my own experience.

To be fair, i have seen loads of Bobs cars go onto the RR's and give figures and curves that are superb - Mine was the only one i have seen that had a problem that was obviously down to map refinement. I would not hesitate in recommending a road only BRD map to anyone - I believe mine was a isolated case and Bobs embarrasment at the time and willingness to get me to Swindon for another session ASAP and FOC was apparent.

[ScoobyMania]

Scoobymania - im not interested in the mudfight either - and bearing in mind individual customers have already been dragged into it is why i dont want to post my own experience.

And as I said before, I think that's the correct approach as well.

To be fair, i have seen loads of Bobs cars go onto the RR's and give figures and curves that are superb - Mine was the only one i have seen that had a problem that was obviously down to map refinement.

And that is the point. neither you nor even Bob could feel that there was a real and glaring deficit in what you ended up with. Most people who do "road only" can't see that bit that's missing either..... It's very difficult to notice something that's not there (IYSWIM), by doing road and rollers, you eliminate that at the start, not when it's actually discovered afterwards.


I hope it doesn't seem like we're trying to be adversarial about it particularly, but there IS a right answer to the question on the other thread, an answer which you've experienced directly.

[ScoobyMania]

Nice info Scoobymania. I did not realise the motec had no AVCS control. Im sure you have been looking at the recent RR V road mapping and the

I looked into this element of Motec today, and they have now sorted the AVCS control, they were a year behind GEMS in doing so though and they sure know how to charge for it!

[WR1 Bro]

Seems I may have started a quality thread here. What a legend I can be....

Thanks to Mark and ScoobyMania for their input.

[bob]

I have not had much luck with aftermarket ECU's had a LINK fitted to a MY2000 cold start and tickover we just terrible. Took it back to mapper a few times but it was never sorted. Went to a rolling road day and when my motor was on the rollers everyone could hear it detting... Mapper was there but said don't worry this will not happen on the road I expect the inlet temps are getting a little high...Well I thought about this...What it was a hot day and I was sat in traffic then had a straight road and booted it... I went to Subaru and came out with the P1 the very next day.
Had the type R and went for Tek3 all seemed ok but once again at a RR was told to watch it as its running a little weak at very high rev's. Told RR's do not see it how it really is on the open road...Got to 150 and it went pop... When mapping on the roads we could only get to about 140 mph so how do they map it for the higher speeds?
Had autronic(sp) fitted to 2.5 type r that was a nice ECU but again the tickover on cold was very low had this lifted but tickover when hot lifted. So lived with low cold tickover.

[marky mark]

think its fair to say that the link is simple compared to some of the other ECU's mentioned. So many people seem to complain about the low down running of them.

[bob]

Thats true but back in 2000 they were all the rage... All the top mappers were saying this is the one to have...
If punters handed there keys to a mapper and come back later would they know if the car was mapped on the road or on the rollers...I don't think so.
I find it a little dangerous mapping on the road the speeds I have got to while mapping would put me in prison but I think after a road map we should listen to the experts on the RR and take advice when they say there is a small problem...

[ScoobyMania]

Thats true but back in 2000 they were all the rage... All the top mappers were saying this is the one to have...
If punters handed there keys to a mapper and come back later would they know if the car was mapped on the road or on the rollers...I don't think so.
I find it a little dangerous mapping on the road the speeds I have got to while mapping would put me in prison but I think after a road map we should listen to the experts on the RR and take advice when they say there is a small problem...

Hi Bob.

It's true, Link were all the rage 6 years ago, heck, even I had one. Original 6 row job.

Things have moved on a long way since then fortunately. I cant think what responsible mapper would attempt to "explain away" det, wherever it was happening. sounds like you drew the short straw?

It IS possible to load the rollers up to simulate loads greater than you might see on the roads,the engine can't reallly tell whether it's on a road or a rolling road, there is a small factor of airflow, but that is marginal with good strong fans.

We do some mapping on the roads at 3 figure speeds, but for real high power stuff, we usually drop down to Bruntinghtorpe as its far safer.

[WR1 Bro]

Motec appears to be the daddy really. They should give you a bit more BHP and torque (maybe 10-15 of each).

Hi Soobymania, on a standard WR1 what improvements do you believe you would get from a Motec map?

This is an hypothetical question as if you were going to this expense I'm sure you would throw a few well selected mods at the car.

[ScoobyMania]

Hi Soobymania, on a standard WR1 what improvements do you believe you would get from a Motec map?

This is an hypothetical question as if you were going to this expense I'm sure you would throw a few well selected mods at the car.

In performance terms, a WR1 with the normal mod's already carried out (decat & free flow filter), I would expect to be able to get circa 350BHP limited by the capabilities of the factory Turbo and injectors. The using Motec part of it wouldn't gain anything over GEMS other than being MUCH more expensive to install.

Edited to add that the Motec set-up would be around

[WR1 Bro]

Hi Soobymania, on a standard WR1 what improvements do you believe you would get from a Motec map?

This is an hypothetical question as if you were going to this expense I'm sure you would throw a few well selected mods at the car.

In performance terms, a WR1 with the normal mod's already carried out (decat & free flow filter), Iw ould expect to be able to get circa 350BHP limited by the cpabilities of the factory Turbo and injectors. The using Motec part of it wouldn't gain anything over GEMS other than being not as tidy an install and being MUCH more expensive to install.

Thanks. I got a bit confused. What benefits would you get from the GEMS over a standed ECU remap?