ECU upgrade. Do it or leave it as it is?

[ChimpOnGas]

Pupp said:

Love the 2 valve v8 comparisons with 4 valve boxers... similar gas speeds? lol

Glad you're laughing out loud, its also unlike you to be pedantic and unnecessarily negative.

I think you must have missed this example too...



I understand where you're coming from though, when my TVR isn't working it makes me grumpy too, fortunately my choice of not to try to go to the moon with it has left me with a reliable car.

A Fiat Panda that that simply runs, is always going to be a million times faster that a rocket ship that's broken down.

[pb450]

I'm a Canems converts. Had mine fitted by an extremely reputable company back in March and haven't looked back. Until.... the MoT. It failed on emissions!

2000 rpm (or fast idle, as they call it) was fine. Natural idle was found to be massively over-fuelling. But then it runs soooo nicely, starts from cold perfectly, runs smoothly, no shunting, blah, blah. In fact the car was in for a service and MoT with my specialist, who runs me to the station before starting the work. On this occassion we took my car with him driving. He commented on how nicely it drove. And then, bang! Fail!!!!

Now as I live around 120 miles from my installer, returning for a quick tweak wasn't an option. My TVR specialist sees an increasing number of TVRs with after-market ECUs and says this is becoming pretty common.

The installer was very helpful and emailed a 'lean' map over to the specialist very quickly. This was uploaded via a laptop and the car ran like st. However, the emissions were just fine and passed all tests. That map has now been retained and the original map reinstated, back at the garage. Normal service resumed, until a repeat performance next year.

There's nothing illegal in what's been done and on balance, I'm happy with the outcome. However, it all seems pretty daft. In the pursuit of out and out power, this is very coomon. But for smooth driving (and lets be honest, a 450 in good nick provides plenty plenty raw power for normal road use) it's madness that such adjustments need to be made. Next year won't be a problem.

So in summary, it seems that over-fuelling at idle is becoming increasingly common with after-market ECUs, causing MoT problems. My spies tell me it's NOT restricted to one particular type or manufacturer. I've fallen victim to this. Any others?

[spitfire4v8]

Did your installer ask you if you wanted it to pass the MOT ? I know it seems an odd question, but on my installs if the car has to pass a legitimate emissions test I always put a lambda=1 map into one of the three map slots on the emerald .. but the bottom line is that even on a lambda = 1 map it should still drive better than a lucas/distributor system purely because you still have control over the ignition. If it doesn't there's something wrong.

[Sardonicus]

spitfire4v8 said:

Did your installer ask you if you wanted it to pass the MOT ? I know it seems an odd question, but on my installs if the car has to pass a legitimate emissions test I always put a lambda=1 map into one of the three map slots on the emerald .. but the bottom line is that even on a lambda = 1 map it should still drive better than a lucas/distributor system purely because you still have control over the ignition. If it doesn't there's something wrong.

This ^ and if it is happy to run on fast idle fueling to enable CAT limits met (which is lean by the way) then I see no reason it should be over fueling on natural idle thats not the area on these cars that need to run slightly rich I am confused, even breathed on motors are happy to run lean AFR's at idle speed its the dreaded around 2k RPM (shunty zone) thats fussy so I feel a simple shuffle around with the idle fuel map cells would have netted you a straight forward pass and I dont mean an over the phone generic tweak or map to load either

[jazzdude]

The emissions at MOT time was something I was going to bring up too.

If these ECus work that way, particularly the MS, having a lean map to turn on or write into the firmware, just before the MOT test is a great plus in my opinion. Personally, any mod that can take out the hassle of changing the Y piece once a year is welcome.

As the previous poster commented on re driving around with his mapped car which ran smoothly but which failed the MOT test, is this not the same as running cars with the cats taken out, only to have a catted Y piece as back up for the test?

[pb450]

spitfire4v8 said:

Did your installer ask you if you wanted it to pass the MOT ?

I must confess he didn't. However, on a road car I would have thought that was implicit.

Sardonicus said:

...then I see no reason it should be over fueling on natural idle thats not the area on these cars that need to run slightly rich I am confused, even breathed on motors are happy to run lean AFR's at idle speed its the dreaded around 2k RPM (shunty zone) thats fussy so I feel a simple shuffle around with the idle fuel map cells would have netted you a straight forward pass and I dont mean an over the phone generic tweak or map to load either

I agree with the logic of all you say. Unfortunately my knowledge of the details is way inferior to 'those in the know'. Seems odd to me too but these guys do know a thing or two. I'll probably talk to them to see if there's a win-win for a smooth idle and staright pass in one hit. Just wondered if anyone else had had similar problems.

[carsy]

Sardonicus said:

This ^ and if it is happy to run on fast idle fueling to enable CAT limits met (which is lean by the way) then I see no reason it should be over fueling on natural idle thats not the area on these cars that need to run slightly rich I am confused, even breathed on motors are happy to run lean AFR's at idle speed its the dreaded around 2k RPM (shunty zone) thats fussy so I feel a simple shuffle around with the idle fuel map cells would have netted you a straight forward pass and I dont mean an over the phone generic tweak or map to load either

Agree with this. if it was just the idle fueling a quick tweek of that particular fuel cell could have leaned it off the required amount.

I read lots about the RV8 wanting to tick over with 13.5 afr and yes it does give a good idle but equally mine will also tick over perfectly fine at 14.7 afr. Allegedly best emmisions for a de catted RV8 is 14.3 afr.

One of the things i have found re tick over afr`s is that air intake temp makes quite a noticeable difference. For example when the intake is nice and cold after a good 70mph blast and you then ask it to tick over you get your correct 14 or whatever afr. Sit with the car stationary ticking over for 5 or 10 mins especially in the summer with the bonnet shut as per mot time and the afr will richen considerably due to the incoming air being so much hotter and therefore less dense.

Obviously there are correction tables to counter this so it may be worth while checking your correction tables. Not saying this is your problem but maybe worth checking.

[v8bloke]

I had a canems ECU with 45mm throttle bodies fitted to my 4.8 RV8 by a well known installer. It never ran right. problems with misfires, over fuelling etc etc.
was a complete nightmare and waste of £3800. I cant tell you how frustrating it was! My new ECU is a Link G4+ extreme which is so much better, yes it has a lot of features that I don't need but a million times better than the by comparison, Basic Canems.

[trev4]

I had what turned out to be a failed coil which was only 15 months old a few months ago that was the straw that broke the camel's back, I to started a similar thread with similar results although the majority of responses were very positive for the main three ECU's there was still quite a few with negative experience's which have delayed my decision to change especially as she is running well now.
Good luck with it, I am going emerald but not sure when.

[QBee]

Mine’s on Emerald. You are welcome to drive it and see how it runs, idles, etc etc.
I work just north of Saffron Walden, south of Cambridge, twice a week if that makes meeting up any easier. I can always force myself to bring the TVR.....

[stevesprint]

Pupp said:

Love the 2 valve v8 comparisons with 4 valve boxers... similar gas speeds? lol

I didn’t know JazzDude's modern daily ride is a “4 valve boxers...” but either way I bet its idle is rock solid like a RV8 with a modern ECU.

ChimpOnGas said:

If I put my PAS equipped Chimaera on full lock the system instantly compensates for the extra load, it does the same when the rad fans chime in .....

I'm referring to modern idle in general to help Jazzdude understand the everyday driving advantages of an after market ECU. To demonstrate try stalling your 14CUX while cold and stationary and as the idle drops below target idle the 14CUX opens the stepper in an attempt to stop it stalling, then when you remove the load the idle over shoots and the 14CUX takes several seconds to pull the idle back down. However, with a modern ECU controling the idle by the spark timing the idle immediately springs back to the correct idle speed, try this at home in gear with your hand brake pulled up hard. In addition an aftermarket ECU can also control the vacuum at the same time so you can manoeuvre without any throttle input and concentrate more on reversing into that tight parking space, where as the 14CUX disables closed loop idle control on the move so you have to control the engine speed the old fashion way with the throttle.

I'm sure COG can explain better, where is he when I need him

The other problem with the 14CUX it has two sets of idle parameters, some for open loop idle and more for closed loop idle control but sadly TVR simply increased the closed loop target idle setting which unfortunately pushes up the open loop momentarily lingering idle to help gear changes and smoothness. This increases the chances of the idle reaching 1,600 rpm when something else is wrong and then the ECU thinks the stepper is faulty and pauses a long time before eventually running the stepper motor test routine that eventually brings the idle down.

carsy said:

One of the things i have found re tick over afr`s is that air intake temp makes quite a noticeable difference. For example when the intake is nice and cold after a good 70mph blast and you then ask it to tick over you get your correct 14 or whatever afr. Sit with the car stationary ticking over for 5 or 10 mins especially in the summer with the bonnet shut as per mot time and the afr will richen considerably due to the incoming air being so much hotter and therefore less dense.

An MAF (including the 14CUX’s AFM) are a lot more resilient to varying conditions and that’s why they are commonly found on mass produced cars.

[jazzdude]

Steve, the only boxer I have as a daily drive is my dog and yes she comes to work with me every day.

This idle valve that has been mentioned in lieu of the stepper motor, how does that work and where is it connected?

Is it recommended to fit one over relying on the crank wheel sensor?

Second, with wide band I understand the lambda is fitted low down on the horizontal section of the y piece, in front of the crank. Is there any advantage in running two of them and if so where are they fitted?

[carsy]

Ive fitted a Bosch 2 wire idle valve. It fits in the original stepper feed pipe. I just cut a small section out of the stepper feed pipe and it fits in perfect as if it was designed for it. I'll try n find a picture.

Id say you only need an idle valve for cold starts. If your happy to hold the throttle open a touch for a minute or two from cold then you probably dont need one as long as your cold mapping is up to scratch. I ran without one for a while but its so much easier with one from cold.

I have an Emerald and it doesnt have closed loop idle control. You can only map the idle valve against temperature. So when your up to normal temp thats it the idle valve has no further use. Having said that with the spark scatter feature enabled my idle is rock solid, doesnt dip with fans coming on or power steeting etc. Infact if your spark timing is bob on at idle, and either side of idle you dont really need spark scatter.

Id personally say One lambda sensor is enough in the Y piece.

Sounds like your talking yourself into it. !!!

[stevesprint]

jazzdude said:

Steve, the only boxer I have as a daily drive is my dog and yes she comes to work with me every day.

This idle valve that has been mentioned in lieu of the stepper motor, how does that work and where is it connected?

Is it recommended to fit one over relying on the crank wheel sensor?

Second, with wide band I understand the lambda is fitted low down on the horizontal section of the y piece, in front of the crank. Is there any advantage in running two of them and if so where are they fitted?

Yes in lieu, The idle valve is a stepper motor and not extra, like Carsy explains thanks, sorry for the confusion.

My point is, if you go for an aftermarket ECU I’m suggesting you have a stepper motor / idle valve as I know a few owners with aftermarket ECUs but without one and have the cold starting issue Carsy explains, but I wasn't thinking of Carsy.

Here’s a picture showing the location of my wide band probe which has proved perfect


and a picture of my AFR gauge as I'm very pleased with it


There is no advantage having two widebands to map the 14CUX as you only have one fuel table to play with for both banks but on the other hand I guess you could use two widebands or more on a fully sequential aftermarket ECU like a DTA or Omaga to balance the banks or cylinders. I guess it depends if you can map the banks separately and therefore will be interesting to hear COG answer regarding his batch firing Camens systems.

Edited by stevesprint on Thursday 12th October 23:11

[N7GTX]

Jazzdude's thread is confusing me now

Trev4 says we are talking about 3 aftermarket ECUs so it looks like Emerald, Canems and Megasquirt 2? I'm not sure I would be spending thousands of pounds to fit a system that still needs an air valve for idle control. I can only assume these 3 options are much of a muchness. If the car is running on the Lucas set up as well as reported, is there any gain to be had for quite a substantial sum of money?
I believe that Megasquirt 3 has more features so I assume it has no need for an air valve? I know that Simon (Sardonicus) is fitting a cam sensor and I guess there is room for knock sensors too. Surely, this is the way forward?

All I know is that I don't have a dizzy, airflow sensor or stepper motor and the car starts when cold and idles quite well really. The troublesome components are gone.
Don't ignore an MBE

[jazzdude]

From what I have read, MS 3 is overkill on the RV8 unless you are looking at FI with advanced levels of engine management with minute incremental tuning settings to wring out every bit of hp available.

It's true I am coming round to the idea of fitting the modern ECU as I said, and I think this has more to do with the challenge and it being a 'nice project' than me expecting huge gains from what I already have.

The 2 wire idle valve for me seems to be a bonus if it adds a control with the cold start idling state and I am happy with the explanations regarding the way that idle adjustment is done with extra load.

I have spent time on the 14CUX and have experimented with different maps, burning my own chips but the fact that making changes on the fly is not possible, as you have to make the change, burn a new map onto the Eprom, while resetting the ECU and waiting for it to relearn, before seeing the results.

With these replacement ECUs I expect most people have their cars set up for them and they just leave it as it is. My main concern now with adjustments being available on the fly in a relatively easier way, is that I will probably not be able to do that and I will be always tempted to tweak it, leaving less time to actually drive and enjoy the car.

Edited by jazzdude on Friday 13th October 06:03

[trev4]

QBee said:

Mine’s on Emerald. You are welcome to drive it and see how it runs, idles, etc etc.
I work just north of Saffron Walden, south of Cambridge, twice a week if that makes meeting up any easier. I can always force myself to bring the TVR.....

Thanks for the kind offer , I know the system works well when fitted and set up correctly.
The car is booked in at Matt's next Tuesday to plug an oil leak so I will have another chat about it then, I would like to get Matt to do it.

[ChimpOnGas]

jazzdude said:

With these replacement ECUs I expect most people have their cars set up for them and they just leave it as it is.

One of the key reasons I went with an aftermarket engine management system was because I came from the old school world of carb and distributor tuning, when I bought my Chimaera some 9 years ago I'd wrongly assumed tuning the 14CUX would be relatively straightforward, how wrong was I

The realisation (at that time) I was completely locked out of the ECU lead me to explore more flexible options, it seemed absolutely ridiculous to me a carb would give me more tuning flexibility than the 14CUX, but thems the facts. At the time there was no Rover Gauge, just Mark Adams, it was also clear to me short of getting my old box of springs a bob weights out of storage there wasn't much I could do to tune the ignition side either. Back in the 90's I studied Bosch K-Jetronic at Norwich City College as part of my NVQ Motor Vehicle Technology (level 5) which shows my age, I then decided to go into restoration rather than take the apprenticeship I was offered at Lotus so K-Jetronic was where my engine management knowledge started and finished.

Having long since decided the motor trade was the wrong direction for me I remained a little regretful I'd never progressed with my engine management learning, so given the limitations of the 14CUX it made perfect sense to look at going to one of the aftermarket engine management systems that lets face it are all early 90's engine management technology with the added benefit of easy access and user friendly software. I studied the options available on the market at the time and very nearly went with the excellent Emerald system, in the end I settled on Canems because it was the only ECU that offered a true dual fuel option which brought an additional interesting element to the party that none of its competitors could offer.

Turning the thirsty Chimaera into a car with near 50mpg petrol cost equivalent fuel economy intrigued me so that's the way I went, I ran the car on petrol only for the first year which gave me all the benefits of the competitor systems like Emerald & Megasquirt. At year two I activated the LPG side and turned a great hobby car that was still rather costly to run, into a vehicle I would think nothing of making my everyday transport.

The sotfware of the Canems system is laughably simple and intuitive to use, it really is super straightforward to setup and tune, OK so you don't get all the bells and whistles you do with say a Megasquirt, but what you do get is all the essentials needed to make a old Rover run considerably better than it does on a distributor and the 14CUX. For anyone with carb and distributor tuning experience these systems are like the biggest box of jets, bob weights and springs you can fit in a second at the press of a key, it's an absolute revelation! I found the Canems system to be my perfect first aftermarket ECU to help teach myself the basics of EFI/ignition tuning, I would caveat that by saying it does help massively if you already have a grounding in the working principles of an internal combustion engine and distributor/carb tuning.

jazzdude said:

My main concern now with adjustments being available on the fly in a relatively easier way, is that I will probably not be able to do that and I will be always tempted to tweak it, leaving less time to actually drive and enjoy the car.

As covered above this is the very reason I chose an aftermarket ECU, with the very simple Canems software and the mistake tolerant low compression naturally aspirated Rover V8 engine as your tuning platform there's very little risk of making expensive mistakes. I ran my Lloyds maps for a year or so while I learned the system, I then deconstructed their maps unpicking them and rebuilding them as I taught myself what worked and didn't work so well. I made the occasional small mistake but the mistakes teach you more than anything else so they are a highly valuable part of any self learning process, ultimately mapping is all about knowledge and experiences gained over a period of time and you never stop learning. That means those who've been doing it longer will always have more knowledge and experience than me, the other element to consider is while we are only talking about the Rover V8 here, every Rover V8 will be different demanding slightly different calibrations to get the best from it, the quality of the mapping is therefore also in direct proportion to the time you're prepared to invest in it because while you may hold a base map for that engine the reality is it's just a starting point.

Paying someone to map your car isn't a cheap business, so there's a fortune to be saved in learning your chosen system as I did, because your own time is essentially free you can invest lots of time in making small adjustments to see if the base map you've paid for can be enhanced. If you screw up it's simply not an issue because your saved original base map can be uploaded is seconds returning you to the map you've paid for in a blink of an eye, this makes the learning process completely safe and as the low compression normally aspirated Rover V8 is a wonderfully tolerant platform to work with you'd have to do something pretty dumb to do any damage.

I found the process of learning mapping to be extremely rewarding, take a systematic approach, use logic and your knowledge of the basic principles of the internal combustion engine and really you can't go wrong, or at least if you do go wrong you can easily go back to where you were with a press of a key on your laptop. Keep the elements where an improvement has been achieved and learn from those elements that didn't work so well because they teach you more about the process than anything else. A strong grounding in carb and traditional distributor tuning really helps, and that fundamental understanding of the way an four stroke internal combustion engine works is essential before you even consider opening the software.

An additional point to consider would be while you can achieve some excellent results mapping on the road you will never really know where peak torque is found unless you can check it on a dyno, there's nothing wrong with tuning by feel and most mappers finishing their rolling road work will conclude their tuning process by smoothing the dyno map on the road because only the road can give you a true real world driving experience. A dyno is a hugely useful tool to conclusively prove if a change to your calibration has been a genuine success or not, but what you're really paying for is the years of knowledge and experience an engine mapper has, so choose your guy with this in mind and try to work with a mapper that has specific experience of your chosen system or you'll be paying for his learning time.

I'm now really at the stage where I could do with moving on to a more feature rich system, I've spent some time looking at Megasquirt and my word that's an exiting system. I'd also love to go fully sequential, it does make the tuning process more complex but there are some real benefits I'd love to explore. Canems now offeres a fully sequential 8 cylinder system born from their work with the LS engine and collaboration with Gardner Douglas, that for me is probably the way to go as the software will be familiar. A fully sequential duel fuel Canems system paired with the Thor inlet where I'm injecting LPG as a liquid would be my dream system, but for now I'm extremely happy with what I have, so given the costs involved I will be fitting the Thor inlet to my current batch fired gaseous system to see how that works out.

Finally keep in mind whichever system you choose it's only ever as good as the installation and mapping work that comes with it, a badly installed and mapped aftermarket ECU will likely give you much worse results than a well setup 14CUX and distributor, while in engine management terms it is a very basic system, it is at least OEM quality and because it worked well from new there's no reason why it shouldn't work well today. These days tuning the 14CUX is possible without seeing Mr Adams which is a huge advantage but I'd still say if further drivability improvements are your goal your best bet is to start by making sure your 14CUX and distributor ignition system is in rude health and well set up, from there with a richer 14CUX map and experimenting with full vacuum to your vac advance module you will likely deliver the greatest improvements for the least outlay, finally by changing the inlet manifold to the Thor arrangement my guess is you'll end up with a super smooth driving Chimaera without spending a fortune.

And all that before you even consider an expensive aftermarket engine management system

[jazzdude]

I think that is the trouble though with these cars, you want to fettle on them even if they are working ok.

I mean I have other cars that have the odd niggle or things that need a bit of attention and I am inclined to leave those until the next service and let the mechanic deal with them. But on my Chim, I do all of it.

So you can see where I am going with this.

[ChimpOnGas]

jazzdude said:

I think that is the trouble though with these cars, you want to fettle on them even if they are working ok.

I mean I have other cars that have the odd niggle or things that need a bit of attention and I am inclined to leave those until the next service and let the mechanic deal with them. But on my Chim, I do all of it.

So you can see where I am going with this.

Absolutely, this is a key part of TVR ownership and is central to the pleasure we extract from these cars, it's classic car ownership at its best if you ask me.

A TVR is a flawed diamond, so close to greatness for such a comparatively small outlay the car torments and teases you into improving it, and for the right person there's nothing wrong with that.

As I've already said if you come from a background of traditional carb and distributor tuning moving to an aftermarket ECU is an absolute revelation, it's basically the biggest box of jets, distributor bob weights and advance springs you could ever imagine. Traditional carb and distributor ignition tuning is a time consuming and often frustrating business, and ultimately your results will always be a compromise. When you get into mapping you suddenly realise with practice you can eliminate all those age old compromises you fought against for years.

The invention of the proper wide band Lambda sensor was game changing too as it gives you a real time window into the combustion chambers, no more pulling over at the side of the road to study the largely unreliable data provided by spark plug colour, you now have true and reliable AFR information as you drive. This sensor changed everything, even if you are running a carb or 14CUX I would strongly recommend fitting a wide band lambda sensor and gauge, it really is a massive game changer.

With a wide band Lambda sensor and any aftermarket ECU you can also implement proper closed loop fueling based on an easy to create lookup table of multiple user defined AFRs, these being based on engine speed and load. With the right base map in the first place this is another game changer especially when compared with the narrow band 14CUX arrangement that lurches rich and lean either side on only one target AFR only ie the often inappropriately lean 14.7:1.

Obviously I have wide band lambda feedback on my Canems system, but sometimes you don't want the laptop open in the car, and some of us don't want to fit an AFR gauge to our TVR dash. That's why I love my AEM X-Wifi, I can have it running on my IPod touch (or IPhone) as I drive, or go back to a stock looking dash in seconds. The AEM X-Wifi also gives me exhaust gas temperature data on each back which is a nice to have tuning aid although if I'm honest is largely unnecessary with the under-stressed low compression naturally aspirated Rover V8, saying that it is worthwhile for me as I run LPG.

Lambda sensor fitted to ACT Y-Piece:





EGT bung welded in the N/S manifold:





EGT sensor fitted:





X-Wifi in action (light load cruise):





X-Wifi in action part load:





X-Wifi in action at idle in closed loop mode with the IPod Touch charging via the USB connector on my Pure Highway DAB head unit:




You can just see one bank of EGT in the above photo but if you rotate the IPod touch into the portrait position the EGT figures on both banks are shown clearly below the AFR reading, if you just want to see AFR keep the IPod Touch in the landscape position as shown in the above photos.



As a middle ground between laptop and AEM X-Wifi I can also use my 7" Windows tablet synced with my Canems ECU for convenient engine data viewing without the need for a cumbersome laptop on the passenger seat.





However even though these fueling control features and data acquisition tools are game changing, they still come second place to the benefits of three dimensionaly mapping your ignition, in truth is with the exception of the vacuum advance module, a distributor is barely more sophisticated than a steam engine governor as it's only advancing in direct relation to engine speed. The advance curve can therefore only be altered by changing the bob weights and the resistance of the advance springs, which is time consuming process and fraught with the very real possibility you'll only ever make the engine drive worse in one area or another.

If you go to an aftermarket system you will invariable start tweaking and adjusting things in the endless quest to find the perfect calibration, these days I make a conscious effort to leave the laptop at home and while it takes seconds to hook up I also try my best not to run my AEM X-Wifi all the time as I find they can distract from the true focus of TVR ownership which should be extracting every last drop of driving pleasure from the car.

Build the perfect map then put all your data acquisition and tuning aids away, concentrate on building that special relationship you can only get with an analogue drivers car