1996 Mazda Mx5 with ITBs - p16 video clip :)

[goldnrust]

Dec 29, 2014 12:01:42 GMT duncanmartin said:

Sounds like you can just about get away with any of the 90s coupes for your daily - that gives you a really good choice. But it would mean that you have to get rid of this MX5 again. And you seem to love your rotaries, which wouldn't be suitable either.

That's pretty much where I'm at currently. Stalemate. Not sure where to go from here.

I did think earlier about just buying a 90s coupe on the cheaper end of things, swapping insurance and stuff over to that and taking the mx5 back off the road for a while. Then I could sort though the niggles with the mx5; sort the sound deadening, rebuild the engine and sort the paint work out. On face value its a good plan short term it gives me the car I think suits my needs at the moment. It also a few months to try out a 90s coupe day to day without having to loose the mx5, and when I'm bored of being comfortable I can get the even more improved mx5 back out to play.

The downside is it probably means no bike project till the mx5 is done, and what if I find myself at this same dilemma when the mx5 is back on the road again, just with me having ploughed more time and money into it?

Sorry loudandproud those options are all a bit too sensible for me The 147 appeals to me most out of them but it would have to be the petrol, and then for the money I'd rather have a GTV I bought a 70's Lancia to daily drive for 2013, I don't do sensible, haha

Duncan, the reason I want to use a 70's is that I want to build something that's relatively true to the look and feel of the 60's british bikes the cafe racer look is all about. For me that means kick start, parallel twin/single cylinder air cooled engine, spoked wheels and twin shock steel frame. The 70's Hondas offer those features for the cheapest price, plus being Hondas they'll actually work, and they'll keep working for ever and ever!

The WR450 looks really nice Lewis A friend has just got a WR400 built up in supermoto trim and it's really cool. Very different to ride to the Gas Gas! Nice looking Monster there too I had a Monster 750 between the CCM and the Gas Gas, it was a much better road bike than the 748 but still had all the Ducati features I liked. When it came down to it though, I didn't enjoy riding it as much as I did a supermoto and I missed 2 stroke, so it left to make room for the Gas Gas

[duncanmartin]

The ultimate question seems to be how frequently you're going to have to be doing the long distance commute. If it's only a few months, then why not buy something cheap, use it and tidy is as is your wont, and fix the MX5 in the meantime. When the commute is shorter, you can sell the 90s coupe and go back to the MX5. But if the commute is going to be long for the foreseeable, throwing time and money at the MX5 is just going to cause more heartbreak when you can't use it.

[goldnrust]

Well I've no idea how much commuting I'll need to be doing this year…so still catch 22 isn't it Duncan!

My thoughts on what to do have been generally evolving over the past week, which as ever is a good sign that the right answer hasn't been found yet! Driving my wife's KA for a few days gave me some perspective on what I do and don't like about the mx5. It very quickly reminded me that I did want a car with a sports car driving position and sports car handling, even if I don't do so many enthusiastic driving miles as I once did.

While trundling down the motorway in the surprisingly quiet rush hour (8:30am on the m40 by oxford and not a car in sight? was a silver lining for having to work new years eve) a car drove by me that gave me a bit of a brain wave…. whats exactly like my mx5, just as much of a small soft top sports car, just as fast, but does 35+ mpg and is much more refined… a mk3 mx5. It seems to combine everything I wanted from a 90s coupe with all the fun of my current car. On the downside its too modern for me really, fly by wire throttle and the interior is a bit plasticy. Still it has superseded any ideas of a 90's coupe in my head.

At the same time I spent some time looking back at all the old photos I have of my mx5, memories of holidays with my wife, summer days messing about with friends, right through to the pictures of it coming back home to me this summer. It reminded me how much I've got to loose. Yesterday driving the mx5 for the first time in a week reminded me just how much I like this engine, a modern 4 pot even with the same power, wouldn't have the same character. Anyway… enough of those thoughts, due to the fun of the cash flow of being freelance nothing major can happen till march, be that an engine build for this car and a temp daily or be that a change of vehicle.

So back to normality, now the mx5 is starting cleanly every time, the Megasquirt map is getting pretty refined now and is generally working day to day, I want to tidy up a few of the details that I rushed in the mad dash to get it MOTed last year. As seen is the last post, I've trimmed the plug leads down so they aren't over long. Next on the list was to tidy the engine bay loom.



Thats where we started from, a mix of multicoloured electrical tape that I thought was 'fun' 5 years ago and over long cables just bundled up out of the way. I spent most of yesterday working my way round the engine bay re-wrapping all the loom in black tape, and shortening any excess wiring.



It's starting to look a bit neater now. Still need to do something about the heater hoses and to sort a proper air filter. I also took some time to trace when the knocking noise in the front left corner suspension. It's been bugging me as with brand new bushes and good condition ball joints I didn't expect a knocking noise! Yesterday I did finally find the source There's play in the left end of the steering rack, so I've ordered some new bushes from Mazda and will rebuild the steering rack once they arrive

[mdh]

How about another bike? Summat less nutty than the stroker....maybe a bigish trailie?

Is your garage big enough for two bikes and the mx?

[goldnrust]

More bikes are always an option Mark Sadly they don't solve my daily driver type issues, I've tried to go back to daily driving/riding a bike since getting a car licence but invariably the plan falls apart in winter. I did it for a few years but it really isn't fun trying to ride a bike to work on frosty mornings, let along when there's black ice out there!

2 bikes and an mx5 will go in my garage technically yes, but there would be no room to work on anything. At the moment with one bike and the car if I move things around there's just about enough room to work on one corner of the car at a time, or to work on the bike.

[loudandproud205]

I don my cap to you as you managed to drive a Ford Ka sensibly for a daily grind, if you can cope with that just about anything in the world is better words fail to empathise just how much hatred I have for those things.

Dailies don't have to be pricey just look around the local facebook pages for something that tickles the fancy box if its not any good then don't plough money in to it sell it straight on, buying at the right price means it won't ever loose money either. Hence the said Audi I bought last year as I was hoping I'd see the Audi craze but I still found it was just a VW in a bigger shell, infact the Audi Coupe wasn't even as nice as the Corrado IMO.

There is always room I have my VFR in my front room at the moment due to loosing a fairing part and acquiring another bike for the shed, the VFR deserves the nicer treatment

[The House]

Daily drivers are always hard to get right, as you tend to still want to enjoy driving it even though its not your 'fun' car...

I ended up going for an alfa 156 sportwagon 2.4 jtd.
With a set of egr blanking plates and a cheap tuning box its crazy fast, yet still gets over 60mpg... and it sounds sporty as its a 5 cylinder
Also has Bose audio, dual zone climate control, full black leather, and only cost me £800!

[goldnrust]

Right time for an update. Last friday, the poor starting returned Pulling the leading plugs, the front plug was dripping wet again.



Oh joy! So there was only one thing for it. Engine rebuild time…. I've onbiouvly done this too many times now, as it only took me 3 hours to pull the engine, working on my own in a single garage!



The first bit of fun of stripping down a rotary engine is removing the flywheel nut. It fought me, and beat my flywheel locker. Seeing as I had a spare but, I decided to go for the drill and chisel method of removing it, which worked just nicely. So far so good…

Next up is removing the flywheel. The general known method involves going wild at the flywheel with a hammer till it's shocked free from the taper. Unfortunately last weekend in my haste, I got too wild and with one hammer blow well wide of it's target I ruined the flywheel.



Yeah thats a decent dent and small crack on the friction surface. Don't wanna be re-using that then. Bye bye £300 The only shred of good news was that the flywheel had come free. Regardless, at this point I swore lots, gave up and came inside for a stiff drink.

After a mental week of work, today my mate Dan and I got back in the garage and pulled the engine apart properly. The bad news just keeps coming……

As we started to take it apart, all was looking good. All looked good in the rear rotor. The housing and plates were nowhere near as worn as any of the 3 previous engines I've stripped down. The rotor bearing and stationary bearings all look good.



The e shaft looks in good condition, the oil pump looked good.



Once we got into the front rotor it all went wrong. The reason it was leaking water into the front rotor housing was pretty obvious:



The front face of the centre plate is pretty damaged and the water seal had been forced out of shape by the combustion pressure. It looks more like a section has broken off than corrosion.

The next piece of the puzzle is the front housing, which shows the gouging and dents that are the tell tale signs of a broken apex seal:



So its been rebuilt before… and not done properly as that housing should have been replaced. I'm thinking the centre plate was damaged while the engine was in pieces, or during the initial apex seal failure. Either way the parts list is getting longer and longer, though this time it seems worth continuing with the rebuild as the rest of the engine is still good..

Also the apex seals, which must have been replaced at the previous rebuild in the front rotor, have been damaged by running round the damaged housing.



Obviously it's not massive damage but if I'm doing a proper job and replacing all the other parts it's surely a false economy to reuse these.

I'm pretty curse word off with whoever rebuilt this engine previously and did a cowboy job of it. Grrr.

[TerraRoot]

well at least the rest of it's good, eh?

About the DD thing, best to get something boring but competent.
example, i have a corsa c 1.0, very incompetent, slow, not boring because handling like custard with wibblepoo brakes is in fact a bit of eye opener/heart starter, i don't DD it, it's a toy to play/break/fix/forget.
My cbr600f2, most competent bike i've ever owned, comfortable (smooth as silk i4), fast, nimble (comparatively speaking), touring, trackdays, starts on cold mornings,
And pretty boring, i only mess with it when it won't go, can't arsed modifying it, hope it'll die catastrophically one day so i can just get some other thing.

That how i describe a daily driver. i went through the same phase wanting a really exciting DD, exciting DD's just become more projects.

maybe a overpowered audi saloon? (not that i've ever been in one)

[Dan_betG]

I disagree.....

As we've spoken about many a time I think you can hit a middle ground with a daily, like you're thinking, an Alfa 147. Mid size family hatch but it's an Alfa so it will have a little bit of something about it.

It's got to be better than running the KA further into the ground

[pittaway]

just read from start to finish, great thread! stick with it!

[luckyseven]

hă´mmer. (noun) A divining tool of almost magical qualities, most often used for destructively identifying the most expensive and fragile item nearest the one you were originally attempting to hit

The housing and tip damage might have come from it swallowing something? I definitely wouldn't want to trust those apex seals again. You'll get rubbish compression and loads of blow-by contamination. Sad times

[camerashy]

goldnrust Your patience with this is actually incredible. I admire it a lot.

I've also learnt A LOT about rotaries, namely, I don't ever wish to own one.

[mdh]

That's curse word luck mate!

Any thoughts of dumping the Dorito motor and dropping a v6/8 in instead?

[goldnrust]

Yeh Nik, I'm pretty sure its from apex seals seeing as the turbo I got with the engine had the good old mashed turbine wheel from the same event.

Camerashy, haha, I normally write the updates once I've had time to calm down after something goes wrong, you'll notice it took a week for me to update after the flywheel incident… haha. That said, all you're really seeing in this thread is the negatives, rotaries make up for all this heartache by being awesome fun when they work!

Yeah the v6 conversions do look good Mark, never been sold on the v8. Still I think the high revving scream my sort of engine suits the mx5 better than the torque and low down grunt of bigger engines, so I'm not sure it's a way I'd go. If I did a v6 swap it would have to be the Alfa buss v6, love that engine, but I've heard it doesn't fit


Anyway I've come up with a plan of action but you're not gonna like it…

I've totted up the rebuild cost as about £1k in parts, including replacing the flywheel. Eeek. I don't have that right now, but I need a working car.

RobinJI is breaking his mx5, so I'm going to grab all the bits I need to drop a 1.6 mx5 engine back in off him. He's got a nice stainless 4-2-1 exhaust manifold to go with it, and I've got a set of throttle bodies in the shed that were destined for my Lancia but never made it. That should end up being at least a little entertaining for a while, at about 1/4 of the cost of the rotary rebuild.

Then when money is flowing a little more freely I can get going with the rotary rebuild.

[adam73bgt]

I like the plan. So long as the rotary finds its way back in there eventually

Having the Mx5 running for a while may give you enough time to work out how to fit the turbo in there also?

[mdh]

Sounds like a plan!

You sure you won't end up turboing the mx lump?

[goldnrust]

It probably will Adam. That said it has crossed my mind that if I enjoy the 1.6 with ITBs lots then maybe I'll end up building the rotary up and dropping it in something else instead!

Turbo rotary in this mx5 isn't going to happen though. 100% about that. Supercharged rotary maybe, ported n/a rotary screamer maybe….

The idea is for this to be a stop gap Mark, so I wanna stay away from stuff like turbos that drink money haha

[MK2VR6]

Sounds like a cracking plan for now. The NA engines are cheap as chips and pretty much bomb proof anyhow. At least this way you get to continue to enjoy the car that so rightly is owned and driven by you. Turbocharging is relatively straightforward though - I'm shortly going to be selling my 1.6 mk1 Eunos which is turbocharged. It pulls like a train and is a hoot to drive. I thoroughly recommend it!

[goldnrust]

Well I'm glad people continue to think this is a sensible plan. Even on the die hard rotary forum they've not been overly mean, I was fully expecting a heavy flaming!

I know all about how the turbo 1.6 feels, before I did the rotary swap I was running ~230hp with a turbo on the original 1.6 engine in this car. It certainly did move, no denying that. It was considerably faster than the n/a rotary has been, and yes it was a hoot!

I've got to say, now I've owned/driven a fair number of different cars, I prefer the predictability and response of a good n/a set-up over the outright power of a turbo.