Is it worth fitting an aftermarket ECU?
Discussion
Slowly getting the engine sorted on my Chimaera. It's a V8 Developments 5-litre Performance engine with a stealth cam running standard Chimaera 500 heads. My carefully calibrated butt-dyno suggests it's running well under its true potential at the moment, so I'm going to arrange some time with a specialist to check all the sensors etc.
How much can you do beyond that on the standard Rover ECU? If I did decide to fit an aftermarket ECU, how much would I be looking at (roughly) for the conversion?
How much can you do beyond that on the standard Rover ECU? If I did decide to fit an aftermarket ECU, how much would I be looking at (roughly) for the conversion?
For me the key words here are new engine,,,
The CUX can be tuned up but it’s still a mechanical dizzy and can’t change or adapt like an after market system with multi point trigger wheel giving almost exact timing figures that the Ecu can use with other sensors to accurately time and fuel the engine for any given circumstance.
Since I went after market my engine runs so clean and uses less fuel or chucks less in especially when starting from cold.
Less Un burnt deposits end up in the oil so the oil stays cleaner for longer.
I’d had a rebuilt engine so the best thing about after market amongst many good things is this ability to run at a perfect condition at almost all times.
So not only will an after market ECU maximise power and torque figures it’s likely to extend engine life expectancy.
Price
Anything from 2k onwards depending how far you go and who does the job.
It’s a car of the 1990’s with 70/80s ignition and fuelling tech
You bring it bang on upto date and into the 21st century on both accounts which transforms the driving sensation from unsure how long it will run for to total conviction
Changing Ecu can involve new injectors to spark plugs to air intake etc etc so the overall cost can often be nearer 3k so a serious commitment but if it’s a keeper worth its weight in gold let alone thousands of trouble free motoring.
Using 8 individual coil packs as opposed to one that gets very hot and probably over worked is a life changer, let alone the power of spark they provide.
There’s a fair old list of benefits if you add them up.
My fuel figures are much better given all the differing conditions we drive in. Your cam profile and when it opens and closes as in its timing has quite a baring on volimatic efficiency within the bores So with a good tuner you should get a crisp running engine which is really the point afterall.
The CUX can be tuned up but it’s still a mechanical dizzy and can’t change or adapt like an after market system with multi point trigger wheel giving almost exact timing figures that the Ecu can use with other sensors to accurately time and fuel the engine for any given circumstance.
Since I went after market my engine runs so clean and uses less fuel or chucks less in especially when starting from cold.
Less Un burnt deposits end up in the oil so the oil stays cleaner for longer.
I’d had a rebuilt engine so the best thing about after market amongst many good things is this ability to run at a perfect condition at almost all times.
So not only will an after market ECU maximise power and torque figures it’s likely to extend engine life expectancy.
Price
Anything from 2k onwards depending how far you go and who does the job.
It’s a car of the 1990’s with 70/80s ignition and fuelling tech
You bring it bang on upto date and into the 21st century on both accounts which transforms the driving sensation from unsure how long it will run for to total conviction
Changing Ecu can involve new injectors to spark plugs to air intake etc etc so the overall cost can often be nearer 3k so a serious commitment but if it’s a keeper worth its weight in gold let alone thousands of trouble free motoring.
Using 8 individual coil packs as opposed to one that gets very hot and probably over worked is a life changer, let alone the power of spark they provide.
There’s a fair old list of benefits if you add them up.
My fuel figures are much better given all the differing conditions we drive in. Your cam profile and when it opens and closes as in its timing has quite a baring on volimatic efficiency within the bores So with a good tuner you should get a crisp running engine which is really the point afterall.
The most problematic components on the original car are the mass airflow sensor, coil and amplifier, distributor and idle speed control valve. Fitting a modern ECU can (depending on the ECU) do away with those parts so that is a cost factor you can eliminate. I'm not saying the Lucas is bad, it isn't, its just bringing your engine management system up to date. If keeping the car I think it makes good sense (but I'm not paying).
If you can afford it then it’s got to be a bonus bringing it up to date and modernising.
This is where my money would go if I were spending it.
http://www.kitsandclassics.co.uk/
This is where my money would go if I were spending it.
http://www.kitsandclassics.co.uk/
We used Joolz at Kits and Classics to tinker with the 14CUX back in 2015. To be honest, we weren’t exactly unhappy with the car aside from a bit of low rpm shunting. It came back a very different and much smoother, happier car.
Power went up from 270 to 290bhp and torque up from 300 to 320 lb ft with his 14CUX tuning options (including the 20AM and CNC blended trumpet base)
Yesterday I picked up the car from Joolz having gone the Emerald route, with wide and lambda and 3 switcheable maps. With no further changes, it’s up to 317bhp and 345 lb ft - so up 8%
The drive back was across a variety of roads, and the car’s manners are further improved. The car just pulls and pulls (320lb ft from just over 2000rpm!) and I really wouldn’t hesitate to recommend an aftermarket ECU, or Joolz.
Power went up from 270 to 290bhp and torque up from 300 to 320 lb ft with his 14CUX tuning options (including the 20AM and CNC blended trumpet base)
Yesterday I picked up the car from Joolz having gone the Emerald route, with wide and lambda and 3 switcheable maps. With no further changes, it’s up to 317bhp and 345 lb ft - so up 8%
The drive back was across a variety of roads, and the car’s manners are further improved. The car just pulls and pulls (320lb ft from just over 2000rpm!) and I really wouldn’t hesitate to recommend an aftermarket ECU, or Joolz.
Edited by Podie on Monday 15th October 10:57
Knock sensors are really useful from a safety aspect so an ecu with this function is well worth having especially with forced induction where things break in an instant if things go tits up. They come at a cost though. Later factory ecu's have knock detection so if those can be mapped you have a huge advantage.
motul1974 said:
Hi Chris, what your engine before the upgrade, I mean was it GEMS type block?....thinking knock sensors??
I ask as I'm just doing a GEMS conversion with the aid of V8D and Mark Adams.
Years ago I built a custom ls1 into a range rover p38 and the owner kept it managed by Gems with support from Mark. I think it's the only LS Gems conversion out there. It also has lpg.I ask as I'm just doing a GEMS conversion with the aid of V8D and Mark Adams.
Chris71 said:
Slowly getting the engine sorted on my Chimaera. It's a V8 Developments 5-litre Performance engine with a stealth cam running standard Chimaera 500 heads. My carefully calibrated butt-dyno suggests it's running well under its true potential at the moment, so I'm going to arrange some time with a specialist to check all the sensors etc.
How much can you do beyond that on the standard Rover ECU? If I did decide to fit an aftermarket ECU, how much would I be looking at (roughly) for the conversion?
I have the same engine from V8D, I took the car to Joolz for an uprated (20am) airflow meter and for him to work his magic, the result was 325bhp and 370lb/ft torque, the transformation in road manners was immense, with cold starts being perfect and driveable instantly.How much can you do beyond that on the standard Rover ECU? If I did decide to fit an aftermarket ECU, how much would I be looking at (roughly) for the conversion?
That was done in 2015 and still remains just as good
Andav469 said:
I have the same engine from V8D, I took the car to Joolz for an uprated (20am) airflow meter and for him to work his magic, the result was 325bhp and 370lb/ft torque, the transformation in road manners was immense, with cold starts being perfect and driveable instantly.
That was done in 2015 and still remains just as good
Do you have a Dyno printout as that’s mighty impressive on Dizzy timing. That was done in 2015 and still remains just as good
How many miles have you done since that day.
What this goes to show is power figures as part of a re map only has relevance to the average owner if the spec of engine rebuild and any other tuning mods are included.
If you take my standard 4.6 engine rebuild it has something in the region of around 25/35ft lb less torque and around 10-25 less hp than Dave’s 5.0 engine which I first thought was rather a lot but then remembered mine was mapped Catted/standard exhaust and running standard trumpets air intake pipe etc. Standard LR heads and has 400cc less to work with and when you add that into the equation the two engines power curves are spot on.
Other than guaranteeing better fuelling,sharper timing at the top end I don’t think after market ECU can increase power much for the top line figures as that’s just what the base engine produces but it can make everything inbetween a bit more efficient especially if you have other mods.
Clearly Joolz can get the power figures regardless of Ecu so the decision to go to a different system must be based on other factors and how much you expect to drive the car or just because you like peace of mind ( priceless) etc etc
For me tidying up the engine bay and removing the old wiring and problematic parts was a big part of the decision.
That and the inevitable reliability that comes with it.
Looking at aftermarket Ecu on the world scene and following some mappers online you soon notice the operating systems for diagnosis are broadly similar with all of them, so any mapper worthy his breakfast housed with the software on his laptop can check and fine tune set ups on many of these systems.
Infact it’s not rocket science on a n/a engine and with wide band lambda or even the low band these Ecu make changes very swiftly and keep everything in its operating window.
It seems like there’s no point a mapper working with one system, he has to work with many so the software has to be useable for these pros to swap and move between them.
For us we have guys who work with a specific system or two so they are going to know it inside out.
With a bit of application many owners can take on the basics of this software as the information and training schools are available online to learn about what all the numbers mean.
The futures rosy so to speak.
If you take my standard 4.6 engine rebuild it has something in the region of around 25/35ft lb less torque and around 10-25 less hp than Dave’s 5.0 engine which I first thought was rather a lot but then remembered mine was mapped Catted/standard exhaust and running standard trumpets air intake pipe etc. Standard LR heads and has 400cc less to work with and when you add that into the equation the two engines power curves are spot on.
Other than guaranteeing better fuelling,sharper timing at the top end I don’t think after market ECU can increase power much for the top line figures as that’s just what the base engine produces but it can make everything inbetween a bit more efficient especially if you have other mods.
Clearly Joolz can get the power figures regardless of Ecu so the decision to go to a different system must be based on other factors and how much you expect to drive the car or just because you like peace of mind ( priceless) etc etc
For me tidying up the engine bay and removing the old wiring and problematic parts was a big part of the decision.
That and the inevitable reliability that comes with it.
Looking at aftermarket Ecu on the world scene and following some mappers online you soon notice the operating systems for diagnosis are broadly similar with all of them, so any mapper worthy his breakfast housed with the software on his laptop can check and fine tune set ups on many of these systems.
Infact it’s not rocket science on a n/a engine and with wide band lambda or even the low band these Ecu make changes very swiftly and keep everything in its operating window.
It seems like there’s no point a mapper working with one system, he has to work with many so the software has to be useable for these pros to swap and move between them.
For us we have guys who work with a specific system or two so they are going to know it inside out.
With a bit of application many owners can take on the basics of this software as the information and training schools are available online to learn about what all the numbers mean.
The futures rosy so to speak.
Andav469 said:
I have the same engine from V8D, I took the car to Joolz for an uprated (20am) airflow meter and for him to work his magic, the result was 325bhp and 370lb/ft torque, the transformation in road manners was immense, with cold starts being perfect and driveable instantly.
That was done in 2015 and still remains just as good
Still on the original ECU, standard injectors etc?That was done in 2015 and still remains just as good
In principle, anyone who can map the CUX14 (it's a more advanced system that most will take for granted, but not exactly rocket science - it's in fact a licence-built version of the Bosch LH-Jectronic that fuelled pretty much every German prestige car in the mid-80s to early/mid-'90s) can achieve the exact same thing as with an aftermarket fuel injection system: get the air/fuel ratio within the optimum range at any given point of the load/rpm map. Once you achieve this, there's no hidden power to be released as by magic, with another system. The fuel requirements of the RV8 seem to be quite relaxed, anyway.
With an essentially unchanged engine/drivetrain configuration (no forced induction, traction control, torque vectoring or automatic transmission to deal with) the main reason to change out the CUX for something different is to get rid of a number of driveability problems you might or might not experience depending on the condition of sensors, stepper motor (the only actuator in the system) and/or wiring/connectors, and/or when you require an integrated fuel and ignition management system. Again, this is more a question of convenience rather than performance; the results of using the existing fuel management system together with an electronic, mappable ignition system will be identical with identical maps.
The suggestion of going for GEMS is a good one if you happen to have an engine built on a late serpentine engine with the knock sensor provisions. Once the target air/fuel ratios for all load/rpm points on the map are programmed in, GEMS is essentially self-adjusting and will cater for a fairly large range of day-to-day operating conditions, engine condition and modifications/optimalisation. As a 'once and for all' solution, GEMS is hard to beat IMHO.
With an essentially unchanged engine/drivetrain configuration (no forced induction, traction control, torque vectoring or automatic transmission to deal with) the main reason to change out the CUX for something different is to get rid of a number of driveability problems you might or might not experience depending on the condition of sensors, stepper motor (the only actuator in the system) and/or wiring/connectors, and/or when you require an integrated fuel and ignition management system. Again, this is more a question of convenience rather than performance; the results of using the existing fuel management system together with an electronic, mappable ignition system will be identical with identical maps.
The suggestion of going for GEMS is a good one if you happen to have an engine built on a late serpentine engine with the knock sensor provisions. Once the target air/fuel ratios for all load/rpm points on the map are programmed in, GEMS is essentially self-adjusting and will cater for a fairly large range of day-to-day operating conditions, engine condition and modifications/optimalisation. As a 'once and for all' solution, GEMS is hard to beat IMHO.
The Gems "self leaning" is an interesting one- I had a chat with the llloyd boys who say they work with it and was told is was basically a fuel trim setting, more than self mapping and re writing its own load point values. No idea myself on this one.
The 14CUX is horrible in catalyst mode, but if you go green tune and then tune the map to what the engine needs, and not the environmental considerations, then it becomes much nicer to drive and the MPG improves. I think a lot of aftermarket systems can be made to work well if you dont stick rigidly to the 14.7:1 AFR the 14CUX is cursed with and its narrow band sensors. Running green tune does mean you have no lambda feedback at all, but as the system uses an AFM , not MAP, its lightly to say in calibration better over time once set up. What I've yet to try is running green tune on catalysts to see if they cook- I think it unlikely as part of the white tune lambda cycle is there just to over fuel the engine, so the un burnt fuel burns in the catalyst to make them work. Hence the warp core temp under your bonnet as wasted heat, not BHP.
The 14CUX is horrible in catalyst mode, but if you go green tune and then tune the map to what the engine needs, and not the environmental considerations, then it becomes much nicer to drive and the MPG improves. I think a lot of aftermarket systems can be made to work well if you dont stick rigidly to the 14.7:1 AFR the 14CUX is cursed with and its narrow band sensors. Running green tune does mean you have no lambda feedback at all, but as the system uses an AFM , not MAP, its lightly to say in calibration better over time once set up. What I've yet to try is running green tune on catalysts to see if they cook- I think it unlikely as part of the white tune lambda cycle is there just to over fuel the engine, so the un burnt fuel burns in the catalyst to make them work. Hence the warp core temp under your bonnet as wasted heat, not BHP.
Classic Chim said:
What this goes to show is power figures as part of a re map only has relevance to the average owner if the spec of engine rebuild and any other tuning mods are included.
If you take my standard 4.6 engine rebuild it has something in the region of around 25/35ft lb less torque and around 10-25 less hp than Dave’s 5.0 engine which I first thought was rather a lot but then remembered mine was mapped Catted/standard exhaust and running standard trumpets air intake pipe etc. Standard LR heads and has 400cc less to work with and when you add that into the equation the two engines power curves are spot on.
Other than guaranteeing better fuelling,sharper timing at the top end I don’t think after market ECU can increase power much for the top line figures as that’s just what the base engine produces but it can make everything inbetween a bit more efficient especially if you have other mods.
Clearly Joolz can get the power figures regardless of Ecu so the decision to go to a different system must be based on other factors and how much you expect to drive the car or just because you like peace of mind ( priceless) etc etc
For me tidying up the engine bay and removing the old wiring and problematic parts was a big part of the decision.
That and the inevitable reliability that comes with it.
Looking at aftermarket Ecu on the world scene and following some mappers online you soon notice the operating systems for diagnosis are broadly similar with all of them, so any mapper worthy his breakfast housed with the software on his laptop can check and fine tune set ups on many of these systems.
Infact it’s not rocket science on a n/a engine and with wide band lambda or even the low band these Ecu make changes very swiftly and keep everything in its operating window.
It seems like there’s no point a mapper working with one system, he has to work with many so the software has to be useable for these pros to swap and move between them.
For us we have guys who work with a specific system or two so they are going to know it inside out.
With a bit of application many owners can take on the basics of this software as the information and training schools are available online to learn about what all the numbers mean.
The futures rosy so to speak.
All good reasons for an ECU upgrade, however, you are making the error of assuming that both Dyno’s read the same, I suspect that if you put your car on Jools Dyno, then the readings would be different.If you take my standard 4.6 engine rebuild it has something in the region of around 25/35ft lb less torque and around 10-25 less hp than Dave’s 5.0 engine which I first thought was rather a lot but then remembered mine was mapped Catted/standard exhaust and running standard trumpets air intake pipe etc. Standard LR heads and has 400cc less to work with and when you add that into the equation the two engines power curves are spot on.
Other than guaranteeing better fuelling,sharper timing at the top end I don’t think after market ECU can increase power much for the top line figures as that’s just what the base engine produces but it can make everything inbetween a bit more efficient especially if you have other mods.
Clearly Joolz can get the power figures regardless of Ecu so the decision to go to a different system must be based on other factors and how much you expect to drive the car or just because you like peace of mind ( priceless) etc etc
For me tidying up the engine bay and removing the old wiring and problematic parts was a big part of the decision.
That and the inevitable reliability that comes with it.
Looking at aftermarket Ecu on the world scene and following some mappers online you soon notice the operating systems for diagnosis are broadly similar with all of them, so any mapper worthy his breakfast housed with the software on his laptop can check and fine tune set ups on many of these systems.
Infact it’s not rocket science on a n/a engine and with wide band lambda or even the low band these Ecu make changes very swiftly and keep everything in its operating window.
It seems like there’s no point a mapper working with one system, he has to work with many so the software has to be useable for these pros to swap and move between them.
For us we have guys who work with a specific system or two so they are going to know it inside out.
With a bit of application many owners can take on the basics of this software as the information and training schools are available online to learn about what all the numbers mean.
The futures rosy so to speak.
Both mine and Darren’s engines are an identical spec, the difference is 20 bhp on Jools Dyno, he is running an aftermarket ECU and so that will be the difference between 14CUX and aftermarket ECU on a normally aspirated engine
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