Motec ECU and LS-7: Harness Adaptor available?
Discussion
I'm planning on changing the ECU in my LS-7 powered Ultima GTR. The main reason for switching is that ever since my mate and I finished the build the stock GM ECU (E38) has only been giving us trouble. It was very poorly tuned from the get-go, ECU locked, etc. Also I'm based in Singapore, and there is not a single GM tuning expert to be found anywhere within a 1000 miles (almost literally).
To cut a long story short, I've found a very reliable Motec expert in my neighborhood and hence I want to make the switch to a Motec ECU. The missing piece in the puzzle at the moment is finding a harness adaptor that would help to connect up the LS-7 harness to the Motec unit. Short of trying to figure this out from scratch and going through a painful wiring exercise, does anyone know whether there are GM/Motec guys out there that have produced such an adaptor before and would be willing to sell one? I have asked Motec but never gotten a conclusive response ...
As always many thanks in advance!
Cheers,
Willy
To cut a long story short, I've found a very reliable Motec expert in my neighborhood and hence I want to make the switch to a Motec ECU. The missing piece in the puzzle at the moment is finding a harness adaptor that would help to connect up the LS-7 harness to the Motec unit. Short of trying to figure this out from scratch and going through a painful wiring exercise, does anyone know whether there are GM/Motec guys out there that have produced such an adaptor before and would be willing to sell one? I have asked Motec but never gotten a conclusive response ...
As always many thanks in advance!
Cheers,
Willy
We had one made just recently for our Ultima GTR Race car which we are running in the British Endurance Championship this year. John Bevan made our loom - you will need to be very exact as to what is required and 'future proof' it because its very difficult to add extra options later.
Here is the link: http://www.bevantecnics.co.uk/
If you discuss your requirements with your Motec chap first, find out exactly what you require then contact John he should be able to sort you out.
Jonny
Here is the link: http://www.bevantecnics.co.uk/
If you discuss your requirements with your Motec chap first, find out exactly what you require then contact John he should be able to sort you out.
Jonny
sounds like you are not getting through to the right person at Motec
http://www.daytonasportscars.com.au/images/file/Da...
this is a story about one of the Motec managers other companies.
http://www.daytonasportscars.com.au/index.php
http://www.daytonasportscars.com.au/engine.html
http://www.daytonasportscars.com.au/images/file/Da...
this is a story about one of the Motec managers other companies.
http://www.daytonasportscars.com.au/index.php
http://www.daytonasportscars.com.au/engine.html
Edited by ezakimak on Wednesday 6th April 00:29
Edited by ezakimak on Wednesday 6th April 00:30
Guys,
There's only a few possible problems:
1. The tune is no good.
2. There's something wrong with the ECU
3. There's a wiring fault.
4. There's a faulty sensor.
Before jumping in with MOTEC, why dont you borrow an ECU and a loom with the sensors and wire it "stand alone".... then change out piece-by-piece to isolate the gremlin.
I'll talk to Jeff and see if he has one.
There's only a few possible problems:
1. The tune is no good.
2. There's something wrong with the ECU
3. There's a wiring fault.
4. There's a faulty sensor.
Before jumping in with MOTEC, why dont you borrow an ECU and a loom with the sensors and wire it "stand alone".... then change out piece-by-piece to isolate the gremlin.
I'll talk to Jeff and see if he has one.
I’d second the recommendation for John Bevan.
He did an adaptor loom for my engine and ECU for running it on the dyno. It was a small job which was of high quality AND I received a 9 page wire/pin scheme which was done very professionally.
He works with Peter Knight (Knight Racing Services, www.knightracingservices.co.uk) who did my LS7. As you’re a long way a away he might be able to arrange with Peter to do a trial fitment before shipping it out.
The other person that I’ve had luck with is Dave Jobbins at Viper Motorsport Wiring Systems (info@motorsport-wiring.com, +44 1933 279443, www.motorsport-wiring.com).
Greg
He did an adaptor loom for my engine and ECU for running it on the dyno. It was a small job which was of high quality AND I received a 9 page wire/pin scheme which was done very professionally.
He works with Peter Knight (Knight Racing Services, www.knightracingservices.co.uk) who did my LS7. As you’re a long way a away he might be able to arrange with Peter to do a trial fitment before shipping it out.
The other person that I’ve had luck with is Dave Jobbins at Viper Motorsport Wiring Systems (info@motorsport-wiring.com, +44 1933 279443, www.motorsport-wiring.com).
Greg
If your set on going aftermarket ecu (i'd stick with the GM ecu as others have said) look into Vipec ecu's. They are really good and are only AUD$2,500 which includes many options onboard like FBW control, knock control, O2, ethanol content, traction control, cruise control and that's all included in the price. ECU mathamatical calculations are the same as motec and autronic.
Ok, have been out of pistonheads for a long time. I'm the other builder
with willy on our project in Singapore.
Basically, we have a gm E38 ECU.
Have installed wideband O2 (AEM, as I got sick of and ditched Innovate LM2)
in order to monitor AFR. Am using HPTuners.
Essentially, problem is as follows.
The engine idles ok, but when the gas pedal is pressed,
and then released quickly (i.e. RPM drops quickly), the
engine starts to drop below idle RPM 875rpm, and then
stalls. (Of course, you can manually depress the
pedal to prevent the stall, but that's not solving
the problem).
In HPT, forced the car into open loop, forced into MAF mode
(SD turned off), tuned MAF around
the 2200-3500 hz region to get AFR ard 14.7 ish.
Guess the question is whether the RPM drop -> engine
stall issue a tuning problem? And if so, which table(s)?
Thx
Bernard
with willy on our project in Singapore.
Basically, we have a gm E38 ECU.
Have installed wideband O2 (AEM, as I got sick of and ditched Innovate LM2)
in order to monitor AFR. Am using HPTuners.
Essentially, problem is as follows.
The engine idles ok, but when the gas pedal is pressed,
and then released quickly (i.e. RPM drops quickly), the
engine starts to drop below idle RPM 875rpm, and then
stalls. (Of course, you can manually depress the
pedal to prevent the stall, but that's not solving
the problem).
In HPT, forced the car into open loop, forced into MAF mode
(SD turned off), tuned MAF around
the 2200-3500 hz region to get AFR ard 14.7 ish.
Guess the question is whether the RPM drop -> engine
stall issue a tuning problem? And if so, which table(s)?
Thx
Bernard
why are you running wide bands?
the e38 will make adjustments to the idle running if you use the GM narrowbands.
the latest motorsport Gm e67 ecm has better idling characteristics than the 38 but the 38 can be adjusted to match the 67.
i will have a look which TABLES you need to work on to improve your problem, ive not used Hp but i imagine it will be similiar.
the e38 will make adjustments to the idle running if you use the GM narrowbands.
the latest motorsport Gm e67 ecm has better idling characteristics than the 38 but the 38 can be adjusted to match the 67.
i will have a look which TABLES you need to work on to improve your problem, ive not used Hp but i imagine it will be similiar.
I thought you guys were running the widebands separate to the narrowbands? If you are not, surely this is the first thing you should look at.
I seem to remember that the engine came with a dyno sheet? If so, change it back to exactly as it was when it was dyno'd. Before you jump in and start messing with the tune, get all of the other variables out of the way.
The other issue when I was there the first time was that there was some exhaust leakage on the Ultima supplied collectors, you need to fix this also as it will affect 02 readings.
Also make sure that everything is properly grounded.
I seem to remember that the engine came with a dyno sheet? If so, change it back to exactly as it was when it was dyno'd. Before you jump in and start messing with the tune, get all of the other variables out of the way.
The other issue when I was there the first time was that there was some exhaust leakage on the Ultima supplied collectors, you need to fix this also as it will affect 02 readings.
Also make sure that everything is properly grounded.
Guys,
My advice is pay for an expert to come over and fix it.
Get Jeff's guy, or someone on here that knows their stuff.... pay them for a trip to Singapore and get this thing fixed.
The way I look at it is you guys did a great job to get the car to where it is, but you are both frustrated because you cant get that last few % over the line.
Ive seen how frustrated you guys are over this and I can tell that this is tarnishing your Ultima dream, you should just pay for someone to go over and fix it and restore your belief in your dream.
The car has sat for how many months? You could have someone there in a week and all your troubles will go away.... AND.... if you take them out on the town in Singapore someone else's dream may be fulfilled at the same time!
XOXOX
GC
My advice is pay for an expert to come over and fix it.
Get Jeff's guy, or someone on here that knows their stuff.... pay them for a trip to Singapore and get this thing fixed.
The way I look at it is you guys did a great job to get the car to where it is, but you are both frustrated because you cant get that last few % over the line.
Ive seen how frustrated you guys are over this and I can tell that this is tarnishing your Ultima dream, you should just pay for someone to go over and fix it and restore your belief in your dream.
The car has sat for how many months? You could have someone there in a week and all your troubles will go away.... AND.... if you take them out on the town in Singapore someone else's dream may be fulfilled at the same time!
XOXOX
GC
Edited by crafty on Wednesday 13th April 02:12
Bernard, I am sorry I am not able to help or offer any sound advice, but if you do not mind making a call to the state. Trying call Mark at Street and Performance. Web site: http://www.hotrodlane.cc/ Between myself and I another Ultima builder we have asked Mark a fair number of questions. Every response he has given so far has been spot-on. It might be worth a call or email to see what he thinks.
Thanks,
Randy
Thanks,
Randy
thx guys.. gonna make the necessary contacts to get this going.
Just fyi, fuel regulator set at 55psi.
Narrow O2 removed, and using WB O2. It's ok as I've forced ECU
into OPEN LOOP, so it will not react / trim fuel according
to the narrow O2 sensors.
Remote tuning from afar, or flying tuner in definitely begin investigated.
Any suggestions on idle/transition tuning for E38 ecu appreciated.
Just fyi, fuel regulator set at 55psi.
Narrow O2 removed, and using WB O2. It's ok as I've forced ECU
into OPEN LOOP, so it will not react / trim fuel according
to the narrow O2 sensors.
Remote tuning from afar, or flying tuner in definitely begin investigated.
Any suggestions on idle/transition tuning for E38 ecu appreciated.
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