The car

I took a long time looking at the car. Having built cars before I know each car has its issues which may or may not have been sorted. This car was without wiring or fuel pipes or brake pipes. There were no front brakes or calipers fitted and I had decided to change the engine and gearbox and prop shaft. The first thing to do was to remove all the bodywork to protect it so off it all came.

20150108_123635 20150108_123801

Gosh what a change. I had done several other things on the way to this picture. The engine had been sorted out with a new camshaft, cambelt, thermostat and housing and triple contact plugs so it would be capable of running. The front brake discs calipers and pads had all been sorted out as well and 15″ wheels and tyres had been sourced to replace the 16″ alloys that the car had when it arrived. The roll bar had been mounted but would still need braces to be fitted in due course. Rack extensions had been modified to give correct tracking. (Roll bar welding and extension turning thanks to N*** whose car it had originally been.)

The engine and gearbox were removed and handed to a guy who modifies the Pinto engine for racing use getting around 170bhp from the engine but at a cost of £3k + !

20150108_125949 20150108_132727

Front brakes were added earlier

20141209_102838 20141209_102855

There was a lot of play in the back left hand wheel so that started a bit of investigation. The first thing I found was that one of the bolts through the suspension crush tubes was 10mm not the design 12mm allowing a lot of play. When I stripped it down the crush tube internal diameter measured 11.5mm. It was too small for the 12mm bolt to go through so I took that out to 12mm and all was well. But there was still too much play. I discovered the book diagram said 13mm holes in the upright which meant 1mm of play with the 12mm bolts. The solution was to now take the crush tubes to 12.7mm and replace the 12mm bolts with 1/2″ bolts which are 12.7mm. Okay lets check the wishbones. The nearside one is the correct way up but the offside one the wrong way. An easy sort. While I am at it I find that the Haynes manual is wrong again. As well as specifying 13mm holes giving play with the bolts the book has two print runs with 10mm difference on the rear wishbones. Earlier books being 10mm shorter and needing 10mm taking off the drive shafts. To make matters worse the jigs to make the wishbones are not altered in the later book. I have the later book but do not know the earlier measurements! You couldn’t make it up. At this time N**** stops answering my questions so I don’t know which the car has been built to. He probably thinks I am getting at him. I’m not its the fault of the publishers for allowing the errors!

N**** has been in touch but can’t help with answers to my questions so on we go.

I decided to fit the Mazda engine and gearbox. I have a hoist and engine mounts sourced from Phil at Talon motor fabrications. Phil is really helpful and makes parts for his Mazda version on the MX5 Roadster. I would have to make a gearbox mount.

DSCF3253 DSCF3251

A bit of a tight fit but it went in well and I then had to sort the gearbox mount out.

DSCF3269 DSCF3257

I got the engine as far back as I could. Made up some 3mm plate to fit on the chassis tubes, used some 50mm box bolted to the engine and put a land rover engine mount between the two. It was difficult to get the stud from the engine mount inserted in the hole in the 50mm box so I made a slot and that seemed to work fine. Checking around to see if everything else was ok I found the clutch slave cylinder would clash with the chassis and I had also had to offset the engine by about 60mm. Try again. Engine moved forward a little and the 3mm plate re-drilled but now one of the vertical chassis tubes wouldn’t allow access to put the nut on the stud or get a spanner in to tighten it.  I wanted to lower the gearbox a little as well. The 50mm box was replaced with some 60 x 40 mm and the back at the nearside cut away to allow access. Success!

DSCF3292 DSCF3290

I will weld everything in place later when several welding tasks can be completed in one go.

I wasn’t happy with the fuel tank. It was about 5gal capacity and was formerly a reserve tank of some sort. It had a fuel sender and an outlet pipe and a filler pipe and cap but was mounted on its side so would need a lot of modification to accommodate a fuel injection system with submersible pump and fuel return.

I decided to change it and found that one of the people on the Haynes forum (K4KEV) would make one if asked. He made an aluminum tank with baffles, an integral swirl pot, breather and filler pipes and also a hole to fit the MX5 fuel pump and it was almost 8 gallons capacity. Together with a very reasonable cost I asked him to make me one. A few days later a parcel arrived which was probably the best packaged I have seen, even having a carry handle.

DSCF3241 DSCF3244

I tried it in place and it fits perfectly, much better than the old one. I’ll get some strap material and make sure it stays in place.

DSCF3240 DSCF3246

I started on the back of the car as the weather got a bit warmer. Firstly I added two 34mm steel tubes to the roll bar braced down to some plates welded at the rear corners. I made some square – ish plates to hold them down with 4 bolts. The top of the tubes were a bit difficult to mitre so I found a program on the internet where you put in the diameter of the tubes and the angle you want them to meet at and it produces a template you print and wrap around the tube in question to give the grinder a guide to cut to. Very useful, it was called tubemiter.DSCF3297 DSCF3325 DSCF3326 DSCF3293

I didn’t like the look of the rear brake backplates. They looked rusty and the brake cylinder seems to exit its connections too close to the upright. I took them off along with the drive shafts and diff. All the parts would be dipped on my electrolysis bucket! – Take one bucket, a 12 volt source of some sort, some water with washing soda and connect the part you want to clean and derust in the bucket, connect the negative terminal, connect the positive to a sacrificial piece of mild steel and leave for 24 hours. Removed, a light wire brush and all the rust and paint is gone ready for repainting.20150306_134752 DSCF3332 DSCF3338 DSCF3340

You get a lot of scum build up on the top of the water, this was after an hour! I didn’t like the way the brake cable had been shortened and also found the cable was coming in from the rear not the front as it does on the sierra so leading and trailing shoes are the wrong way round, that’s two things to sort out later. Whilst I was looking I saw the brake cylinders were ones with a 20.55mm piston fitted. I don’t want my rear brakes locking before my fronts so these will be changed to Ford Ka cylinders which have 17.5mm pistons but are physically the same size. I also wasn’t happy with the CV boots on the drive shafts. They were all cracked with age. I took them off and with the aid of a lubricated cone replaced them with new ones (you slide the new boot over the cone which is fitted over the joint allowing the boot to shrink onto the drive shaft. A few cable ties and its done. Its very messy though)

DSCF3346 DSCF3347

DSCF3349 DSCF3348

There was a lot of painting of bits as well

DSCF3337 DSCF3342 DSCF3344 DSCF3345

On the uprights I found that the lower tubes RU6 were missing so I made some up and welded them into place.


All the bits back together
All the bits back together
Bottle Jack Scales
Bottle Jack Scales

I got the idea for this from the Haynes forum. you get a cheap bottle jack from ebay (£8.25) and also a hydraulic pressure gauge to read up to 1000lb or more (£2.90). Dismantle the jack and drain the fluid, drill and tap the side to take the gauge and then drill a very small hole all the way into the pressure part of the jack. Clean and reassemble. You must measure the dia of the piston. The gauge reads in pounds per square inch so if you know the surface area it is acting on you can work out what it is lifting. I my case that means multiplying the psi by 0.7 which will give you the weight of the thing being lifted, in this case the car. At the moment the front of the car weighs 229kg front and the rear 160kg, it will be nice to see what it ends up at. (There are videos on you tube about how to do this in more detail)

I’ve started thinking about brake pipes and initially was going to weld a bracket on the rear hub and put a pipe from the brake cylinder to it and then a flexi to the chassis. At the Haynes forum one member, Vought, suggested another way. He suggested a 45 deg angle to the pipe at the cylinder so it will clear the upright. I got him to make up a set and yes it works fine, his web site is

bent pipe DSCF3378

You can probably see the car now has a set of  Gaz shocks on it as well, shhhh, spent a bit more than I should this month 😉

Another part of the brakes was the master cylinder. I have arthritis so wanted to keep the servo. I also wanted the clutch and throttle so cut the bulkhead from my donor MX5, cut and re-welded it to bring the clutch and brake master 1 cm closer and welded it in place. Whilst I was at it I also built a box to support the upper bolts carrying the pedals and changed the Sierra steering column for the Mazda one. This meant creating a few universal joints and adding a spherical support bearing to the column. I hope the photos explain what I mean below

DSCF3407 DSCF3408

DSCF3412 DSCF3410

DSCF3436 DSCF3437


Now its time to sort the engine out. New cam belt kit fitted, inlet polished, cam cover painted. The plugs and leads were replaced at the same time.

DSCF3442 DSCF3451

DSCF3452 DSCF3453

It all seems to go  rather easily writing this – didn’t seem so at the time. Brake and fuel pipes went in and I was luck to find which hold 2 8mm fuel pipes and 1 5mm brake pipe at the same time and only 40p each – but you have to buy 100, I’ll sell what remains after finishing with them 🙂

DSCF3468 DSCF3469

DSCF3472 DSCF3470

An aluminum sheet of metal will be fitted to support the pipes by the diff

I decided to cut down the lock to ensure self centering is as strong as can be as it gets weaker beyond a certain point. I pulled back the gaiters and undid the knuckle screwed into the end of the rack. These were supposed to be held in by a punch deforming the metal at the joint. Badly done at manufacture and wouldn’t have held so on reassembly I used thread lock instead. I managed to find some bearing shaft collars on the Bearing Boys web site for a couple of pounds which were the exact size I wanted. Fitted and job done.

DSCF3359 DSCF3360

Radiator brackets were made with the aid of CAD (cardboard aided design) and the radiator was fitted. Its a VW Polo rad and the MX5 fan fitted perfectly with some of the pull rod fasteners from china at only £1.10!

DSCF3473 20150716_091000

I started doing the wiring – its a nightmare. There is far too much of it! Its for a basic 1.6 Mk 2 MX5 and it has all sorts of wires that are not needed. Aircon, not fitted but the wiring was, electric windows, yes its got the wiring and lots of other extra wires that finish in a dead end not fitted to anything.  I start by trying to remove all the wire that’s not needed. Then I try to put it in the car to see how it fits and to see if all those labels I put on the connectors as I took the donor apart were worthwhile.

20150714_160546 20150715_142547

DSCF3474 20150726_161638

Then I found the reason the car had been difficult to get going. The ECU had got wet a few times in the cars history and some wires and individual pins in the ECU connector had corroded away. I tried to get the pins out to replace them but found them very difficult indeed. I located some connectors on Facebook (MX5 Buy and Sell Group) but having paid for them I am still waiting for them 3 weeks later.

I’ll get on with something else

This problem nearly finished my build. I replaced the ECU plugs but still couldn’t get the car to run. I checked everything I could. Wires, earths connectors etc until one day I took the ecu apart. It was corroded inside and lots of the circuit tracks just didn’t exist! How on earth had the car run in the first place! A second hand ecu, ignition key and lock and immobiliser computer later and it finally ran! I did have some electrical problems though – the alternator did not charge, on the MX 5 it is controlled by the ECU, this was tracked to a wire I had cut out by mistake and bit by bit I checked all the electric I was using, lights, horn, original speedo and instruments, fog lamp etc. This little problem took me all the way through the winter and into the next spring.


I needed an exhaust and tried a few companies but it looked like £500 plus for an exhaust. I decided to make my own. I bought a 400 cell weld in CAT from ebay for about £50 and a stainless silencer from MJ exhausts in Walsall for a similar price. It was the biggest I thought I could fit on at 22″ x 6″! There was a problem – it had a forward facing seam that I thought would fail IVA. I found a saucepan lid and cut a hole in the center to slip over the exhaust and for the other end a stainless curry bowl, after a hole and some metral bashing it fitted the other end, both cost 10p at a boot sale.

I then went to a local exhaust fitter and raided their scrap bin for various sizes of exhaust pipe with straights and bends for free. I also bought a Mk 1 manifold for £5 on ebay  which does 4 into 1 as the Mk 2 one I had did 4 into 2 then some way later 2 into 1. I cut up the pipes and welded them together to fit the CAT and exhaust on the side of the car and then wrapped the manifold and CAT in heat wrap as I wanted to keep heat away from the under bonnet area and also to stop anyone standing by the car burning themselves on the very hot CAT. Total cost just over £100 and I was very pleased with the result.


The sides and rear tub were glued on with a polywotsit sealant similar to Tiger Seal, can’t remember the make but it was for sale at £1 each tube at a steam rally, brilliant stuff but oh so very messy. I used pop rivets as well at about 100  mm intervals.


I made the grille with some 6mm stainless rod I bent as a stiffener and welded to form a continuous loop. My Mig stopped feeding the wire so I took it apart and found a relay which would allow to feed to work for a bit if you tapped it. You can only seem to buy a complete board from Sealey and repaired boards I found to cost £40 or so. I read the code off the relay and sourced one from germany for about £4.50. Here is a picture of the relay if it happens to you.


I used the now welded steel frame as a former and bent some stainless mesh around it then trimmed all the loose ends off afterwards.I held it in place in the nose cone with two cable ties as the Westfield company do with their sevens. This is it partly done.


I fitted all the lights and set them up with an old advertising board to line up the headlamps. The indicators I mounted on top of the wings. I still fitted a repeater, initially mounting it on the rear wing but then read the IVA manual which says it cannot be more than a certain distance from the front of the vehicle so had to fit them in the tight radius of the front wing.

Around this time a friend got his car to IVA stage and I towed it to Norwich on the day. A really valuable experience which helped me prepare for my own IVA. I would recomend shadowing another test if you can. Here is a photo of the Spire setting out to the test center.



A very nice car and we nearly passed except on brake balance. It took a morning to fix and 5 weeks before a retest could be done where it passed easily.

My car was bout finished now so I applied for an IVA date but still hadn’t driven the car. Through a race friend I managed to get access to a race track nearby. I was quite apprehensive and wondered if the car would be unmanageable. I started it off slowly but by the end of lap one I had full throttle and by the end of about 100 laps was drifting it through the corner, brilliant!



When I got home I saw that the front wheels were not in line and put it on my tracking gauge. It went off the scale. Eventually I found the cause. The very nice looking stainless steel wishbones at the front had been made using 3mm steel for the bottom ball joint mounts and not 5mm as per the book. My test date came through as well. No time to mess around. I contacted Phil at Talon Motorfabrications who quickly made me a set of wishbones. Having no time I painted them and got the car back together.


Then it was 3rd Oct 2016 and the dreaded IVA at Norwich. I was in luck as it was Dennis who was doing the test, the one who had done the Spire. He had been very good on that occasion.


I arrived early and took the straps off the car while waiting. Dennis arrived and opened up. and we went to the IVA building (still labeled SVA). First he made us a coffee and then it was an ID check of the cars welded on VIN and also the makers plate I had had made. Then emissions. Gosh so many things checked all over the car on the floor and on the ramp. Then checking all the lights, fuel cap, seatbelts and also the heights of mounts as well as their strength. Next came brakes. Lots of measurements here with both the engine running as there was a servo and with engine off. Dennis wore a device on his foot which recorded pedal effort while the rolling road recorded the amount of brake effort. He would later do some calculations to see what percentages of front to rear braking there was across the whole range of tests. Very thorough indeed. Next came the speedo on the next rolling road. Again a range of measurements at 30 to 70mph at 10 mph intervals. He complemented my speedo accuracy, I was relieved. I was using the electronic sender from the MX 5 gearbox which normally drives a 4.1 diff and 185/60 x 14 tyre. I had calculated that my 3.92 diff driving 195/45 x 15 wheels would be within 1% of the original when read on the speedo. That relied on the accuracy of the Mazda speedo being correct. In the end it read 2 mph fast at every speed.Whew! Then a short drive and Dennis came back where visibility from each of the mirrors was checked, a trip to the weighbridge and back to the IVA building. Denis allowed me to fix a couple of things. Some trim on my flyscreen was needed and to tether my fuel cap and adjust the tracking. Another short test drive and it had passed!

I took the car home and sent off the registration documents. I was checking a few days later and saw that when I had copied all the documents before sending them I had missed out one of the receipts I had the original and the copy. I phoned DVLA and spoke to a very helpful Danielle. She said – no problem scan it and send it. I went on to ask how long registration would take and she went on to say she would find my file and do it herself that day. How good is that! At 4pm I got an email from her with my registration number at 4pm that day, just 11 days after the IVA. I got some plate made up and after fitting took the car for its first drive – gosh its quick 🙂




Leave a Reply

Please log in using one of these methods to post your comment: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s