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Luke's Nb Build

15340 Views 177 Replies 15 Participants Last post by  RemoteFX
I'm starting my own build thread since my project build has recently started up again.

I bought my MX5 4 years ago. I bought the car as a daily driver but also to do track days in. Over the first year I did basic mods before going on track days.

GCF Roll Bar

Meister R Coilovers

Sparco Sprint Bucket seats

Sparco steering wheel

Hel Braided lines

Mintex pads



I did my first track day and loved it. Did my second and hated it. I was at Donnington. The track was over booked, loads of red flags, people over taking both sides. Just not a good day with hardly any track time. It was also at this time I found the chassis rail rust. So I fell a bit out of love with the MX5 and the idea of doing more mods.

I also did a Caterham experience day at Silverstone, so for a while all I wanted was a kit car.


After that I just continued using my MX5 as it was for the next 2 years.

Last year I got a new daily driver and did another track day at Donnington and loved it. The level of driving was excellent and got loads of track time. Even at the start of the day I knew I wanted to make my car more track focused and wanted more power. As with many MX5 drivers have experienced, I would catch many cars through the corners but come the straights cars would pull away, then i'd catch them again in the corners.

So with my love for the MX5 back I started ordering bits for a turbo build.

First off was a new radiator from Tegiwa





This was a great job, really fun and great to be working on the car again.

Then more parts started coming in.


Coolant re-route kit


Intercooler and pipework



Then a friend of a friend works at a RX8 breakers so I got some yellow injectors at a good price and cleaned them up.



I also got an ME221 ECU installed.



After this I decided to start stripping parts ready to fit the AEM wideband and continue with turbo specific upgrades.






However when I jacked the car up to take out the O2 sensor, the exhaust was so rusty it either might not come out without the exhaust falling apart or I wouldn't get the new one in. Either way id be without a driveable car. So at this point I decided that if the car is not going to be driven I should get all the underside sorted before anything else. If I carried on and got it turbo'd it would be very hard to then park it for a month or 2 to sort rust and bushes etc.

So off with the suspension it was.




Then stripped down, sand blasted and powder coated.




I've ordered all new ball joints, drop links and rod ends. As well as a set of polybushes.

Next up Im taking the cleaning even further and I'm going to take off the front subframe. This will allow me to get the whole front sorted. There may be a few rust patches that need welding on the inner arches. I have a friend who can weld but at the moment I'm thinking I want to buy a cheap welder and learn myself. This will also allow me to do the rear sills and arches too later in the year.

So that's where I'm at today, due to shift work I won't be able to do much over the next week or so but i'll update when I make more process.


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Ok so even if the ecu is damaged the starter motor is still going to get power from the ignition switch and crank. Is that correct?
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I was again looking at the wrong table, I was looking at flex fuel.
Here is the main cranking trim. The figures still seem low?
ECU is definitely damaged. I’ll send it off to Motorsport electronics for diagnosis and see if it’s repairable.
Ah! Bad luck. At least those damaged tracks are fairly obvious. ME ought to be able to patch around the breaks and will have a good idea of which if any components might have suffered. With luck it's just been a rush of current through ground rails and the rest will be okay. Keeping my fingers crossed for you.
Yeh that’s what I’m hoping for, that it’s only the back plate and not any components.
ME replied after seeing the photos. They confirmed the trace that burnt out is the main power line to the ecu. They will have to test the ecu to confirm if any components are damaged.
They did say that this failure is consistent with power and ground being connected the wrong way round. The garage did use a booster pack to try and start the car so that could be the culprit.
Ill see what the garage say on Wednesday, hopefully they are willing to accept the mistake.
Blimey, really hope they help you out.

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They did say that this failure is consistent with power and ground being connected the wrong way round.
I thought modern ecu's had polarity protection circuits 🤨

my ~15 year old DTA has so I'd have thought ME would have included similar:unsure:

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I guess not. The ECU is with them now. I should know the extent of the damage soon.
Car is on the trailer and I’m heading home. Unfortunately the garage weren’t willing to accept any responsibility. They persisted that it wouldn’t be weld damage and that the booster pack was only ever fitted correctly. They believe I have a bad alternator, bad wiring somewhere or water has got the ecu.
So all I can do is hope for minimal damage and an easy ecu repair.
Well, it went in running and came out broken in their care. Id be pursuing further.

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That was my reasoning going into the conversation. As I was there I phoned ME for them to explain what they had messaged me. During the call they said that they can’t be certain of what caused the damage and said it could be multiple things. So that didn’t help my argument. They then spoke about faulty alternator’s etc. To which Steve at the garage said everything he did was correct so it must be a coincidence. He is willing to spend the day with me when I get the repaired/new ecu to check over all the electrics.
His other argument was that the passenger floor was damp, so he said I can’t rule out water damage which isn’t his fault. Even though the carpet at the ecu was dry.
I’m not pleased about it, but I couldn’t see how I could argue my side anymore and not just be in a stalemate.
I then said if I get a new ecu and I have no further issues. Would he then accept responsibility. His reply was, could be an intermittent fault.
Not good feel for you. Does not add up to me.

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On the phone to ME last Wednesday, he asked if any bulbs had blown on the car. It was during a 3 way discussion with the garage so this got dismissed and moved on. Anyway I have checked today and the number plate bulbs are blown, front and rear indicator bulbs are blown, and main headlight bulbs are blown.
Any electrical gurus have any thoughts on this. Also the brand new fully charged battery is now dead.
when I got to the car the ignition was in the on position, so I’m hoping it was just left on by the garage.
If not with the car doing nothing, no ecu fitted, could anything drain a battery?
On the phone to ME last Wednesday, he asked if any bulbs had blown on the car. It was during a 3 way discussion with the garage so this got dismissed and moved on.
always listen to questions, even if they sound odd or trivial(y)

I have checked today and the number plate bulbs are blown, front and rear indicator bulbs are blown, and main headlight bulbs are blown.
thats a lot of bulbs on different (& switchable) circuits🤨

could anything drain a battery?
cold weather can flatten an old battery:unsure:

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Only time ive seen bulbs blow like that is overvoltage..bulbs arnt polarity dependent.
Alternator regulator slight possibility or workshop grade jumpstarter on truck voltage...24v???

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Thanks guys. Is overvoltage and shorting different?
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