Hi there. It’s my first post to this site but I wanted to say hello and announce my new MX-5. It’s my first MX-5 and I’m delighted with it so far.
It’s a 2007 NC zsport but from then on, it’s been extensively modified. It has a 2.5 litre Duratec engine, plus a BBR/cosworth supercharger, Wilwood calipers and larger discs on the front, Michelin PS Cup 2s and ohlins dfv coilovers to name a few bits. I think it’s producing around 300 bhp, but I need to get it on a rolling road. So far, so good and I love it. I live in Knutsford, Cheshire so if anyone sees me bopping about, come and say hello!
It certainly feels that way. I was going to get a standard car as then do some mods myself as I want to do track days next year. This car came up on eBay though and I took the plunge. So far, so good and I’m loving the handling just as much as the grunt.
Looks excellent. I’m not far away and often in Knutsford. Also, I’m pretty sure I’ve driven past it a couple of times! Nearly put a ‘spotted’ post on here the other week in fact - is it now on a private plate by any chance?
Hi mate. Yes that will be me, it’s now on P25 BBR. I decided to give it a little present for behaving well in the first month of having it. Hope to see you around!
Wow lovely looking car and sounds like a proper bit of kit. Hope you enjoy it and I will look out for you hopefully on a track day as I too would like to try one or two next year all being well.
Fantastic stuff, thanks for messaging. I’m delighted with the car. Funny you got in touch today, I was on track in it for the first time a couple of days ago and it performed well. As I’ve got an opportunity to speak to the man who worked on it a lot, a few questions if I may?
The clutch slips a bit in cool weather. Can’t work out if worn or perhaps it’s not quite up to handling the engine power?
I assume the diff is standard. Someone mention that an updated version might be better for traction, something like a Quaife. What do you think?
If I wanted a slightly harder brake pad for the front, what would you recommend ?
I guess it’s a few years since I sold it but it was a great project and glad you are enjoying it.
I think I still have full spec listed if you want ( I even imported the engine from the US and fitted it with Kelford cams
On your questions
I fitted a stage1 clutch I think - which was always plenty for the torque. But it had a little judder when hot and was either defective or misaligned. The issue got much better over time.
My suspicion is that maybe the next owner might have put in a standard clutch to solve the judder issue. If the clutch it silky smooth even when hot then I would suspect this.
On a cold day the supercharger is extra gutsy and makes more torque = clutch slip.
Brakes : I think I had CL RC5+ pads in the end which were expensive semi track. Would be good to check if someone has changed them ( unlikely?). The car is so much faster than standard that maybe it needs “full on” track pads.
Diff is the standard Limited slip unit - worked well. I’d only fit a quaife if you are having issues but It seemed to work well.
Couple of things to note if you are tracking it.
- car was actually tuned with the decat fitted. ( it is v-banded in ). Hope you have the bypass
- watch out for supercharger temps. Achilles heel. I had 2 pumps and a big rad in an attempt to manage. But the SC pulley is small so charger is nearly maxed
Thanks so much for taking the time to reply and with such comprehensive details.
Would love the spec sheet when you have the time. I did get one with the car from the eBay vendor which I’m guessing is likely what you sold it with but I’d like to see it anyway.
Based on the spec of the car as sold / as I bought it, the clutch is still staged as a stage one so I’ll keep using it and monitor.
On the super charger, how would I monitor those temps? I have an OBD reader but I don’t think this data point is on there. Would it be something I’d just check after each run on track?
Interesting on the engine, I’m guessing it was probably one of the first 2.5 conversions in the UK at the time. What mileage was on the car when it went in please? I was told the engine was only about 4-5k miles old when I got it
Again, thanks so much for contacting me. I love the car even more now knowing the high quality work and TLC that’s gone into it.
I’ll dig out the spec sheet …. but it’s probably the same as you have already. The forum won’t let me post a PM yet so i’ll just post here again.
Supercharger: Basic checks: Standing looking at the engine bay, open the reservoir on the left side - the top is can be a fiddle to unscrew. This is for the supercharger coolant. Check it has fluid. Now turn on just the ignition and it should have a really strong swirl in the fluid. ( Shows the double pumps are running ok).
In terms of temp management, one way is to fit a temp probe. But a reasonable way is to just locate a coolant tube for the SC and after each track session check it with your hand. It should stay “luke warm”. Also - let the engine run for a bit after each session to avoid it all heat soaking. This is all probably worrying about nothing!
In terms of the the engine, it was from a written off, side impact 2018 ford fusion (US mondeo) with ~1k miles on it : imported and installed in 2020 so you can work out the approx miles from the MOT history which is “not many”.
And yes - among the early 2.5 conversions so followed the US crowd due to the plentiful supply from Ford US.
Thanks again for such a detailed response. It’s great to find out so much about my little car.
Supercharger - I’ll take a look at the above when I’m next with the car. Is the supercharger fitted a BBR/Cosworth one as opposed to one of the early generation ones that caused some engines to go pop? I think it is but I’ve tied myself in knots hunting around the internet to understand it.
Thanks for the detail on the engine, that all stacks up with what the vendor told me last August. I’ve no reason to doubt him as everything he told me at the time has proved to be correct but it’s good to be able to check directly with you as the seller didn’t own my car for that long.
There was never anything wrong with the superchargers but instead the early piggy back mapping ECU which was suspected to have poor adjustment for heat and knock. = problems !
I removed this and had it mapped on the original ECU using ecuTek and many road tests / logs. It should be super safe !
Back the to clutch issue I’ve mentioned before. It seems to slip more often than not, and with another trackday booked for the end of this month, I want to get on with getting it sorted.
From looking around online it sounds like the Excedy clutch might be running at or even over its limit. Is a BOFI Racing Stage 2.5 Clutch Kit any good for the torque mine is kicking out?
The exedy stage 1 clutch gripped very well when I had the car. Zero slip. I have feeling something might have gone wrong…. but you won’t find out until it’s off.
All I would say is don’t go for any type of paddle clutch and the bofi one looks like it will do the job nicely but good to find a person who has used it
