'89 Mazda RX7 FC - The Run-Up to the Weekender

Forward on about 18 months and Ive got a better job and work on the truck is no longer raiding my wallet so I look at the rex and feel bad for it. I knew the most painful part was the engine. It was smoking and struggling to idle. So I spoke to some guys and eventually sucked it up and shipped it off.

The plan was basically to get it ready for a big turbo swap but keep the standard for now. Unfortunately due to some personal issues at the garage it took far longer than first expected. Then that rule I broke got in the way... turned out someone had done some nasty splicing on the loom and the injectors and fuel pump were al kinds of wrong. So more time and money later to get it sorted and finally after almost 10 months I got the call to pick it up. In the end I had the following work done:

- Street port
- FD Inlet Manifold
- FD Throttle
- Apexi ECU
- Pulley and belt swap
- New clutch plate
- New down pipe (the old one fell apart)
- 1680cc secondarys
- Modified fuel rail
- Fuel pressure regulator
- A lot of rewiring!
- A few other FD bits here and there

I've been told this should be good for up to 450bhp, I only really want 350 so will see how the standard turbo goes and make a choice on upgrade from there.


Before:


After:


Unfortunately it also returned with news that the turbo was shagged...

Woo! Bookmarking this for sure as that engine spec sounds pretty fun That wiring looks horrible though, mine had a couple of wiring bodges but wasn't even close to being in the same league as that!

Do enjoy an FC, would not enjoy that wiring.

Good luck with this project
I do like these cars
My brother had one (he had two at one point) he done loads to it "upgraded brakes/suspension/wheels and tyres" and more importantly the engine
He had a highly tuned FD engine with big single turbo
And as he was a panel beater by trade the outside was mint
BUT
He had so many problems along the way (including 5 engine rebuilds) he just lost all interest in it and sold (cheap)
Such a shame because by the time he sold it the car was so sorted
Someone got a real bargain I almost bought it myself

A few weeks ago I went to make a start on the sills. I actually managed to get two sill panels brand new from Mazda for a good price so thought it might be easier than expected. Never a true thought!

Started cutting a hole in one corner:




Unfortunately the results were worse than I thought. The inner and outer skin were gone but the middle skin that runs all the way up the A-pillar had also started to go:




I sort of panicked at this point. Considered cutting my losses but couldnt sell it knowing I would never get to experience an engine I paid for! Next I thought about reshelling it, asked and looked about and found nothing. Almost considered importing one from America as it worked out cheaper than my other options. In the end I called out a local restoration company and they gave a fair (albeit still large) price so I committed and gave it to them. Its currently at a sand blaster then should hopefully be back in a couple weeks.

Once its back I need to swap the turbo then take it back to the engine builder to have it mapped, then I can see if it will even pass an MOT.

However I have treated myself to something I've wanted for the two years since buying the car, JDM rear lights:




Essentially the same as the standard ones but theres extra material on the inside of the reverse lamp so I can fit a square plate without blank space. The other cool part is they have little windows on the side for the license plate bulbs so I can smooth the bumper as the standard ones are hideous. Only issue is I have no bulb holders for them and Mazda don't sell any, and I cant find any other shared models. Got some generic ones coming I'm hoping will secure if not may have to get inventive with LED rope and grommets.

What follows are the pictures the shop took of the repairs.



















From them giving me a quote to having the car back again was only a few weeks and the price was really good. Now I know the sills and rails should be good to go. Still not a solid car its a bit crusty but I am happy now that its not going to just fall apart on me. Plus now I have actual jacking points again!
















As I said, not perfect but I'm not too concerned. Most of this I'm planning on replacing anyway and already have parts for a lot of it. The bay is the main issue for rust now but I'm going to live with it for a season at least. The engine may come out again next year anyway so I will address it then.

Now some meat with your veg. The turbo was curse word. Straight bent over a table curse word.

So what's that.




That's a distinct lack of turbo.




Ah yes. That will explain all the smoke and generally sad running.




Unfortunately the turbo wasn't the only obviously buggered item, the exhaust manifold has this rather nasty looking crack running through it.




Oh well, I'm hoping the larger turbo plans do happen next year and it will get replaced anyway.

So here is the old leaky turbo looking in envy at its cleaner and better clone.




And just like that it was back in… Well not quite it was actually a complete ball ache that took 4 days. Most of that was because the bastarding weather couldn't decide what it wanted to do. I walked in the back door in beautiful sun and out the front door in curse word rain. At one point I got caught under the car in torrential rain, I made peace with it and just assumed that was my new home…

So has everything cleared up and I've now got a beast of a rotary? Er, no. It wont start. I mean the car has no map on it so its sort of a miracle it started to get on the tow truck, but now its completely gone. It will occasionally cough and splutter but not enough to keep going on its own momentum. The plugs are showing a lot of oil being thrown around so I didn't want to keep trying before I flooded the poor thing (which I mostly have done anyway). So now I'm waiting for a slot to go and get the mapping done hopefully.

Then the big scary MOT.

Which speaking of, apparently you need both a fog and a reverse light, the greedy buggers. So I checked my fancy new lights and… I had neither. I also worryingly never noticed that there is no fog light on them any more. Apparently the Americans and Japanese have no need for fog lights and instead just hurtle in to their low visibility doom like men, or idiots posing as men.

Now a quick poke around what used to be the fog light got that connector working no worries, Ill likely just put in a red light for the test. The reverse light on the other hand, was a pain.

Now I'm no electrician but I know a couple things. Out with my pundland special multimeter, okay there's 11v on the plug (the battery at this point was 11.5v so I didn't make the obvious assumption just yet). Clearly this meant the light must be shagged, swapped in the now working fog light and nothing. Not even a glow or a flicker.

Back out with the multimeter, definitely 11v. Bulb back in and no photon emitting wonderment. Okay light out, on the test bench (the floor of the living room), test PSU hooked up (old computer PSU), 12v in and boom we have light.

Light back in the car, plugged in and still nothing. So I start poking around the loom plug and there's 11v everywhere. It was getting late so I thought Ill charge the battery and see if that remedies the situation (I told you I'm not electrician, because I knew even then that wouldn't work but still tried).

Next day, battery back in the car, nothing. Then I decided to do something actually intelligent and check the resistance on the plug. 600 ohms, 600 chuffing ohms of resistance. The poor bulb was barely getting dripped on at a couple of milliamps, not my idea of water sports!

So I start tracing the wire all the way back to the fuse box, fuse is fine. Resistance is nominal. Sigh, under the car we go. Traced the line all the way back to the box but there was no hope of me reaching the plug. On the old google we go and apparently this is not that rare. The switch gets covered in road grime which leads to the massive resistance. There is however a simple solution.

You don't need to drive the bulb with the gearbox switch, you just need to know its active. So in comes Mr Relay to save the day. The tiny current trickling down the wire is just enough to switch a relay.

Now when testing relays please put a load and fuse on the circuit…




Otherwise your test leads start to melt and the car comes incredibly close to an electrical fire, not fun! With the smell of burning plastic firmly inhaled I did it properly this time. Here have some pictures of a test leads and a relay. No its not exciting but this is a rather long wall of text.








This last picture is interesting (if the idea of international wiring differences of lights gets you off, hey I'm not judging!) as that is an OEM splice. That splice means the drivers side light is wired to be both a reverse light and a fog light. This means I can have two reverse lights with no extra wiring required. Excellent news because singular reverse lights can die in a fire, I want to see where I'm going on both sides thank you.

That’s it, that’s all I have to write about. Go away.

haha any FC saved is a good thing in my book! And having looked at the price of replacement convertible tops recently, I partly wish I had a coupe!

There are still a few selling for less but they come up so rarely, I think theres two for around the 9 grand mark, a red one and a black one which have been on ebay for ages now

I think its a bit optimistic myself, but if they're going to pull up FC values in general, I won't complain too much!