Thinking of building a kit using as many parts from an early MX5 - can anyone tell me is it possible to run these cars with carbs rather than EFI and would it be an expensive move.

Also is the MX5 Eunos ok to use parts from as seen one cheap locally with low miles as its an import?

I have a lot of mx5 running gear if you're interested

front/rear hubs, uprights, brakes and diff

Hi welcome and suppose you could convert to carbs but i would def keep injection,

eunos should be ok to use i would have thought depends what kit you are going for ??

also im just down the road from you cornish hall end

5 miles from haverhill

cheers
sean

Not sure which way/kit im going for yet as doing me research first. Did like Avon/GBS Zero but they use Sierra bits and these parts are getting pricer and harder to find.

Also I like the idea of a small 1.6 lump. As its going to be a fun car for me and my kids to build, wanted something fairly straight forward.

road runner sr2 and mnr vortx + mk indy do mx5 based kits good options for you,

cheers

sean

eunos roadsters are identical to mazda mx5s in all but very small details like seatbelt reels, cat overheat light, number plate lights, trim...etc etc

all major mechanical components are identical

i'd try keep the injection if possible, if only for drivability, but there are mx5s running carbs so it's certainly possible. you could go throttle bodies with a megasquirt

I thought the eunos had LSD as standard?

So if I used major components from the MX5 and changed the engine to carbs or smiliar, would I still be able to get it through an IVA and register as an age related car. Seeing as I have changed the specifications?

20th century engine with 19th century technology?
Stick with injection or go for TBs if you want an upgrade.

MX5 is defo a good choice of donor but keep injection system or i doubt you will get thru the emissions test at IVA. I like the MNR kit it would be my choice.

if it is an import, it has some more BHP as well.
Only eunos v specs had viscous LSDs. Normal eunos had open diffs.

Beware though.

MX5s have been really messed around with. You can see normal MX5 where the owners have changed the badges etc to look like eunos.

right, most 'special edition' (s-special, v-special, R limited etc) import mx5s came with the option of an LSD. the 1.6s came with a viscous LSD if fitted and the later 1.8s came with a bigger crown wheel and the LSDs were torsen rather than viscous. early ones were type 1 torsen, later ones were type 2. the 1.8s have a shorter propshaft to accomodate the longer nose/damper on the diff and different half shafts. can't remember what model, possibly the mk2.5 sport or RS ltd came with a tochigi fuji clutch LSD

iirc, only the mk2/2.5 sports and mk1 and 2 RS Ltds came with LSD as STANDARD

the 1.6 imports had exactly the same power (115bhp) as the ukdm cars up to 93 where the 1.8 was introduced (130bhp). at this point, JDM 1.6s were discontinued and UKDM were fitted with a detuned engine making 86bhp to broaden the gap between 1.6 and 1.8

you can tell an import by an 11 digit iirc, chassis number. ukdm cars have 17 digit chassis numbers. this is the definitive check.
tom

ETA - yep, definitely 11 digits. just checked my v5

out of interest, how many of the above statements are made by people who've ever owned an mx5?

[Edited on 1/7/10 by indykid]

I have owned 2 miatas

never had one. I know a couple of things because a mate had one and also, the guy that i was buying parts for my build was very knowledgeable as he was breaking MX5s for breakfast.

[Edited on 2/7/10 by l0rd]

Just about to start a MNR VortX MX5.
Nearly finished stripping a Eunos 1.6.
As said above, keep the injection, it will pass emissions without any mods. Speak to Chris at MNR.
There is one IVA'd & on the road now.
You can use the engine, box, loom, uprights, diff, prop, driveshafts, column, clocks & lots more. Eunos diff is viscous LSD
The VortX is also Cortina geometry, not Sierra like a lot of the others, and has inboard suspension.
HTH
GeorgeM

GeorgeM...thanks for the update and one thing you said is that the MNR vortx has Cortina geometry......in simpletons terms.....what does that mean as I knew some uprights used are Cortina/Sierra based. But you said your using the Mazda uprights....so...how does this = Cortina geometry.
You can tell I new to all this cant you

Hi Talk to the Roadrunner racing lads they will tel you all you need to no about MX5 and how to turbo it at a later date, They have got a very lively standard 1.6 in a white SR2

Don't know if it is relevant but would changing over to carbs affect the ecu with regards to the variable valve timing?

Just a thought...

VVT was only on some of the mk2.5 engines so probably wouldn't concern most peple building a kit from one as i imagine they'd be looking at mk1 or early mk2

iirc, only some ecus will run it and megasquirt isn't one of them. mr slow on mx5nutz.com would be able to tell you all you need to know though
tom

Thanks, I was thinking of our friend here, whether it'd be an issue but I realise that I was misguided...

Somebbody told me that the lead going in to the back of the head was a stepper motor for vvt; I guess that particular lead must be for a timing sensor or the such?

M