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Mk1 Eunos 1.6 Project

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27K views 183 replies 39 participants last post by  Zed.  
#1 · (Edited by Moderator)
Hello, this is my third MX5 after a break of a few years whilst I restored an old Karmann Ghia. I've had a mk2 & a mk3 but always fancied a red mk1 :)

It's a '91 Eunos Roadster which I picked up as a project car for myself to tinker with this winter. I'm hoping there's not too much major to address the sills and arches all look really solid, ironically this is the fifth car I viewed all of them a lot more expensive than this but all had signs of rot or bad previous repairs to the sills.

The vendor was a nice chap but didn't have much of a clue about the car so hadn't advertised any of the extras that I found when I viewed it.

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So far I've found it has an ARC chamber, stainless steel exhaust manifold and I believe the whole system (although it was a bit hard to tell in the mud!) a quickshift is fitted (which I hate), plus some sort of adjustable suspension (you can see dials on the bottom of the shocks) Aircon seems to work but time will tell, interior is a bit dirty but not ripped or torn, plus the vendor threw in the hardtop which is a little rough round the edges but a bonus.

The car hasn't had much use (or love) over the last year that the previous owner had it, but seems that owners prior to that have looked after it well.

Initial tasks are:

- A tappety engine turned out to be low oil which seems to have gone away by it topping up with oil and giving it an Italian tune once warm ;-)

- A few of the belts seem to intermittently squeal - so will work my way through replacing those

- General oil change, plugs, service etc.

- Unknown age of cambelt - plan to change this along with water pump, various gaskets, camshaft & crank seals etc

- There's a suspension rattle (quite a lot) but the steering & suspension seems to be quite taut so I suspect it's the ARB droplinks or similar - investigate &repair where needed

- Replace quickshift with normal one

- Paint - give the whole car a good mop to get rid of the classic red paint oxidisation

- Hood - seems sound but the rear has a loose flap that needs attention - if it doesn't leak I will leave it alone until the weather gets warmer then I will have a go at replacing if necessary

- Drivers door has slightly sagged so needs adjustment, ordered some of the solid door bushings to go on at the same time

- Front number plate plinth is cracked - may replace or even move to below the grill

- Replace stereo with something that doesn't have buttons the size of grains of sand and that I can actually read without having to pull over and squint at it. (honestly who designs aftermarket stereos these days? Makes me wonder if they have ever driven a car)

- Replace the naff 15" wheels and ditchfinder tyres with a set of Panasport 8-spoke wheels I have squirrelled away in the garage

- Fit front & rear lower chassis braces (need to check it doesn't have them first)

No doubt after getting to know the car in the next couple of weeks there's be more…
 
#79 ·
do the holes line up with anything- seat perhaps?

good job so far.
Thanks, just found this on a fellow Nutzer's post, looks like it goes behind the ECU and the holes are for nothing in particular, but the little notch at the top probably lines up with one of the ECU fixings perhaps.

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#80 · (Edited by Moderator)
Heater repaired, dash all back in & working, fixed a few bits of trim whilst I was at it, rust repaired the ECU brackets and kickplate, dried out the sound proofing & refitted. Also took the opportunity to try my home-grown induction kit with a couple of tweeks. It now sounds most agreeable :)

Gratuitous engine bay shot with all the new bits:

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#83 ·
Fitted a spacer for the exhaust as I was having alignment issues after I fitted the silenced de-cat. The rear box was being pulled out of alignment due to the manifold+decat combination I'm using are about 20mm shorter than standard. I bought a pair of 2" exhaust manifold flanges off eBay and repurposed them as a spacer with gaskets sandwiched inbetween them. This has given me the desired 20mm spacer and the rear exhaust box & tailpipe now lines up perfectly :)

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Also too the opportunity to raise the Meister R coilovers back up a bit (approx 8-10mm) as I've been grounding the car a few times recently. The fronts are nearly at the limit - you are supposed to keep an eye on the inspection hole in the shock base and make sure there is at least some thread left in it (see picture)

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Lastly, finally got round to fitting all the domed centre caps & retro Mazda badges on the Panasports. I think they finish the wheels off nicely :thumb-up: Oh and I made some 18" racing roundels out of some sheet magnetic Vinyl so I can take them on/off when the mood suits me!

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#85 ·
Yeah I need to raise my crd's too. I park in an underground lot and everytime I scrub the bottom, luckely I have rails
Did you leave it like in the picture or did you lower it down again to cover the hole?
I rang Meister, they said as long as there is some thread in the hole its OK.
 
#87 · (Edited by Moderator)
Car looks great, was it the front lip that was scraping? I'm a tad lower than you but running no front lip.

Trying to source some centres for my panasports, looking for some that'll sit flush with the wheel.
It was the rear chassis brace and the centre of the frame rails that was scraping, made a horrible noise last year on the ramp into the Eurotunnel shuttle !

I used to use these centres, from a Saab 9-5 I think with Mazda badges. In the flesh the domed ones look a lot nicer than the modern centrecaps.

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#88 · (Edited by Moderator)
Visited the Spa Classic last weekend stopping off at Chimay and had a great time, took the Mazda out on the track where it didn't disgrace itself :) managing to keep up (most of the time) with a real mix of cars!

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However after 900 miles of driving over the weekend it started to consume a lot of oil. No leaks but blue smoke from the exhaust and a sooty tailpipe. By my calculations it used just over 2 litres in 900 miles, and the last 300 miles it went from full to under empty (see photo)

Power is good with no misfire so we suspect it's probably the oil scraper rings which wouldn't show up on a compression test.

On reflection I did know this was coming as nearly two years ago when I bought the car it sounded like a bag of nails until I filled it up with a couple of litres of oil and the tappets noise went away. The price was haggled down accordingly so I've had my fun out of this engine.

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The decision is whether to replace with another 1600 or to take the opportunity to upgrade. Turbo sounds nice but I'm not sure I want to go down that route just yet as I really enjoy the instant throttle response & high revving nature of the 16v engine. Supercharged is an option as I loved my old mk2 supercharged but the choices for SC seem to be thin on the ground at the moment. I did consider getting a complete rusty mk2 RS and transplanting everything into the car but not sure the neighbours would appreciate the car on bricks look for the driveway ;)

Current thoughts are for a 1.8vvt conversion as they seem to be much more plentiful, newer design and I've not seen many reports of them failing like the older 1.6NA engines are with age & neglect. So looking for at the moment:

- 1.8vvt engine

- controlled by ME221 which means I can keep the vvt throttle body and crank sensor (no CAS) also means the fan switch can be controlled by the ECU & not by a relocated fan sensor

- 1999/2000 fuel rail & FPR to change back to return fuel system

- mk2 5 speed box (mine is noisy so take the opportunity to change it now)

- change VLSD for Torsen, using 4.1 ratio rather than 3.9 to keep the final drive down rather than the 3.6 or 3.9

- change driveshafts & propshaft to fit the torsen

Of course those are today's plan and who knows if I'll change my mind tomorrow but thanks to Skuzzle and Motorsport Electronics for answering all my questions so far on how it can be done :thumb-up:

Plan would be to get donor engine & parts, service them before installing back into car then take it down to Skuzzle to get it running properly
 
#89 ·
Did a compression test last night:

cylinder 1 - 215psi

cylinder 2 - 210psi

cylinder 3 - 220psi

cylinder 4 - 220psi

Done whilst warm and dry, tried a wet test on cylinder 1 and it went up to 300psi so didn't bother with the rest! Spoke to AK Automotive who said it sounds like the oil scraper rings are the culprit. Also interestingly they said that the VVT engines suffer from the same issues eventually, they are just newer so may not show immediately until after I put one in the car. Making me rethink that perhaps rebuilding what I have might not be such a bad idea after all.

Perhaps send the head off to Blink for their stage 1 kit at the same time whilst it's out. I do enjoy the way the 1.6 engine revs and drives a lot more than my old mk2 1.8 which didn't feel nearly so alive!
 
#90 ·
Sorry, what's this about VVT engines having issues?
 
#91 ·
Sorry, what's this about VVT engines having issues?
Just that the vvc engines can suffer from the oil scraper problem as much as my 1.6. Sounds obvious but makes me think that rebuilding what I have, may long term be better than chancing a used unknown engine
 
#92 ·
cheers.
 
#93 ·
It is interesting reading about this issue. It seems to affect all engines MK1-2.5, perhaps more so 1.8s based on a few threads. Miata.net has a few posts that suggest people applying additives directly into the cylinder as a last ditch effort to save an engine that is probably going to need a rebuild.
 
#94 ·
It is interesting reading about this issue. It seems to affect all engines MK1-2.5, perhaps more so 1.8s based on a few threads. Miata.net has a few posts that suggest people applying additives directly into the cylinder as a last ditch effort to save an engine that is probably going to need a rebuild.
Ah that will be the 'Marvel Mystery Oil' which I've read about. Not sure how much I can take seriously something that has such an obviously bogus name but some people seem to swear by it. Wonder if anyone here has tried it?
 
#97 ·
Looks like a picture of my 1.6 pistons before the rebuild. I was in the same situation. Oil burning 1.6 umm'd and ah'd about getting a 1.8 and rebuilding that but you have to factor the extra cost of sourcing another engine and the unknowns. Ended up with a spare 1.6 head for ÂŁ30 and slapping some new rings on the pistons and giving the block a hone. In hindsight I wished I'd gone with your option as you'll get more power off the bat and can still super/turbocharge if you want.
 
#98 ·
Ok so it looks like this is turning into a bigger job, what I thought was a noisy gearbox turns out to be loads of backlash in my VLSD so that needs replacing as well :rant:

Bit worried that there aren't any decent 4.3 diffs out there - this is my second VLSD I've gone through and if I move to a 4.1 then am I going to notice much of a loss in acceleration...
 
#100 ·
So I've managed to source a low-ish mileage drivetrain from a 1999 mk2 1.8iS that was scrapped due to rust. Not picked it all up yet but I will have:

- 1.8 NB engine with all ancillaries

- matching 5 speed NB gearbox

- propshaft

- driveshafts

- 4.1 Torsen diff

This means I can rebuild or refresh this engine before I install it, and still enjoy the car during the summer (albeit burning oil)
 
#101 ·
Engine's here! spoken to the previous owner of the car it used to be in before it was scrapped for rust and it sounds like it has been well looked after which is a great re-assurance :thumb-up: I was toying with stripping it down but it sounds like it was still going strong when in the car and has been well serviced so will treat it to a new clutch and maybe lighten the flywheel then stick the whole lot in :)

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