1996 Mazda Mx5 with ITBs - p16 video clip :)

I've just realised what's wrong with this car. There's one thing it badly needs!

...replace the weird Mazda toilet-seat/blob-stick/triffid badge;




...with a natty rotang superman FD stylee one;



Then it'll be much moar perfick enuff . Bloody excellent work on the MOT, by the way dude. Another one does the resurrection shuffle

So there's no snail yet?
Clan I book a ride too?

Cool. Now add turbo and make use of those low comp rotors! :-)

It's been a busy few days with the car back on the road, plenty of issues to work through. I'm slowly remembering how to drive this old thing again





The biggest issue by far has been getting the ECU map somewhere near. I've done a good number of miles while data logging and using the auto tune feature on Megasquirt that gets the fuel map somewhere near. The spark map is still roughly the same as on my last engine, I'm aware that it can be pushed a little further at the top end with these low comp rotors but first and foremost I need to get the around town drivability sorted, so the spark map is fine for now.

I was having some issues with kangerooing on light throttle, which was solved by fitting a restrictor to the MAP line, which smooths its response a little and by getting the acceleration enrichments dialled in better. My biggest issue though, has been idle control. The light weight flywheel makes the idle control much more sensitive and so getting a good solid idle has really been a challenge, especially when coming to a stop as the revs drop very quickly. I think I cracked it tonight though, the main change was to tweak the RPM at which the idle control activates up a little, giving it more time to catch the idle.

To make things even more fun, my AFR gauge stopped working on Monday, it turned out to be a wire that had dropped off its connector in the end, which was a nice simple fix. I was worried It meant new wide band controller time!



There's been a few shake down issues, the bolts on the lower inlet manifold worked loose, which lead to a small coolant leak and a vac leak, but I nipped them back up and touch wood all is ok. The alternator belt also started squealing, I'm not sure if the belt stretched lots as it bedded in, or if the alternator bracket slipped, either way I'm going to keep and eye on it!

I was getting some pretty mean heat soak with my intake air temp sensor just mounted in the engine bay, so I moved it directly into the path of the intake air, which has meant that it recovers from the heat soak quicker. It did mean a bit of a redesign of my budget temporary air filter, the IAT now sits inside it. Please don't judge me on the classic old pair of tights air filter approach, it is temporary! haha.



It's slowly starting to feel like a car again, as all the small issues getting ironed out. One thing I have realised over the past few days is that I must be getting old, as I'm not willing to live with quite the same level of discomfort as I once was in a daily driver! The exhaust was monstrously loud, to get it down to an MOT-able level I built a dB killer/baffle type thing, which so far has stayed in the exhaust for the sake of my ears on the motorway and the neighbours! But hopefully that can change soon. Today I got post!



An Rx8 rear exhaust section. Just going by the size of the damn thing, it should be pretty quiet! It's going to take some work to fit, but it should be equally as quiet as my current set-up and much better flowing.

On the subject of noise, when I de-moused the car I ended up ditching all the stock sound deadening, as it was either mouldy or mouse chewed, I thought it wouldn't make much of a difference. I was wrong… on the motorway the road noise is loaded than the damn exhaust, even without the baffle! I've done a small test of shoving an old quilt cover in the cavity between the boot and the parcel shelf, and that's made a surprising difference to the road noise already. So in another concession to this being a daily driver, I'm going to get some sound deadening stuff and do all under the carpets properly. I don't want it to be quiet like a new car or anything stupid, just not 'I need ear plugs for the motorway loud. haha.

Finally for tonight, I'm trying out what is a very marmite mod. I've made a temporary gear lever extension.



It's not because I'm a wannabe drifter, or think it makes it more race car or anything… its actually because I prefer the slightly lighter action and longer throw. I'm used to the 70s long throw of the Lancia box, which I liked a lot, and the longer thrown on my FB Rx7, which uses the same gearbox as the mx5 but with a different gear lever design. It's now about the same length as the FB Rx7 gear lever and I'm enjoying it so far. I'm going to give it a couple more days and might tidy it up a bit if I decide to keep it

They're available in the US;
parts.arlingtonmazda.com/products/ORNAMENT%2C-FRT-%28NA04%252d51%252d711%252d14%29.html

Shipping is a killer though.

Mark

IIRC up until 1986 (so up to the FC model RX-7) it's a visual check only for smoke. After that until 1995 or so it's a pre-cat test, so higher HC and CO emissions levels are allowed than the normal MOT emissions levels... albeit even a cat-equipped FD will sometimes fail these . After that, so for later FDs and RX-8s it's the full-on draconian "how dare you murder fluffy bunnies with your exhaust" test

Thanks Mark. Some of the tyres I've seen have got more white writing on them, I quite like the asymmetry of only having on one side f the the personally

Cheers for the link Garra I'm gonna try and get one made up in the UK, should be cheap enough once I find a good hi-res image of the Mazda logo.

Yeah as mine is an '89 engine in a '96 shell and the MOT test is done on whatever is oldest, I can put mine through the pre cat 3.5% CO test, which it barely passed even with a cat fitted… I'm hoping that next year with a properly dialled in ECU it'll pass with less messing about.

Yeah the 13b has got a pulse width modulated idle control valve, and I'm using closed loop control yes. Touch wood, I've got it sorted. Most of my idle issues revolved around 'catching' the idle when the revs dropped quickly, with the light flywheel they drop even quicker than usual and when pulling up to junctions they would just keep dropping and the engine would stall. Most of the guides say to activate the idle control valve as late as possible, 2-300 rpm above the intended idle speed, with my engine revs falling so fast this was just too short a time for the idle valve to react before the revs had already dropped past the point of no return. By setting this activation point to 500rpm above the target idle speed (1000rpm) it's given it time to react. The downside of setting this number higher is the chance of it still trying to control the idle while under normal driving conditions. As it is, I'm not often trying to drive below 1750rpm, so if the idle activated at 1500 this isn't a problem. Worst case, it'll close the idle control valve right down to try and keep the revs down and when i do let off the throttle when driving around below 1500rpm the revs may drop, so far so good though!

The mx5 lever has, as you say, got the pivot point moved a little higher which reduces the throw, it is also physically shorter than the Rx7 lever. The mx5 lever can feel kinda flick of the wrist 'snickety' when everything is well, but this is actually an old Rx7 set of gearbox internals and I think they are a bit tired, which meant with the mx5 shifter it required a firm shove to change gear. Which was another reason why I'm trying this extension out. I did 100 miles for work today, I feel quite used to the gear lever now and I quite like it.

You could check out this website: www.brandsoftheworld.com/ they have a lot of vector logo's. Which you(or the sticker company) can scale to whatever size you need.

love the mx5, great engineering!

Although saying that they seem ready enough to find on Google just not as a white border, I can always put that together if it's of any help?