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Looking into options to swap out my aging original 1.6 with 262,000Ks/rattlers/crappy valve stem seals. & one of the options is a 98 NB6 1.6 long block engine from Japan/UK. & I don't really know a thing about them. Apart from they have solid lifters & a better crank.

Would this be just as much work to swap in as a NB8's 1.8L? I gather it'd be possible to re-use my original ECU but is it still pointless like it is with 1.8 conversions using the 1.6 ECU?

Basically is it the same as a 98 NB8 1.8 engine but with smaller internal CCs?

Uses the same MAF/2 four wire oxygen sensors (??)/throttle body/manifold/exhaust/belts/filters/coilpacks etc as the NB8??

Originally I'm looking for a late model original 1.6L (early 90's one) rather then 1.8 for a simple drop-in/re-use some of the components already on mine & driveaway to keep SA transport authority & insurance happy but thought I'd at least find out more bout this NB6 stuff.

You could use the engine but you would have to swap a fair bit of gear over if you want it to be simple. If you use your existing intake manifold it should make things easier, as well as fitting your CAS.

I know the intake manifold will bolt straight up to the later model head on the 1600 but I am not sure what is involved in getting the CAS to fit. If the later model valve cover doesn't have allowances for it you could possibly remove the front cam trigger and fit your old cam cover.

I think the rest would be pretty easy...

From what I have been told, the later model head should give you a good fuel economy increase and a bit more power.

Keep us posted!

Just sold one, they are a top little engine!

As for the rest of the stuff, you should be able to reuse it all as long as you keep your old intake manifold. If you change the IM things get tricky as you will have a different throttle body, idle bypass valve, TPS, fuel rail etc.

well the long block isn't coming with the intake manifold or other accessories anyway.

at the moment i'm strongly leaning to saving myself the headache & getting the original kind of 1.6, preferably rebuilt/reconditioned but i may have to keep saving up for longer to get one.

Everything should bolt up to the nb6 engine, BUT it does not have the drive slot in the back of the cam for the cam angle sensor. This can be fixed by taking the inlet cam along with a na6 one to a competent engineering shop, and having them splice the end of the early one onto the late one, it has been done before.

Tim

no drive slot ey, so whats usually back there on the NB6? did Mazda just plug/cover it up?

looks like i may well be getting one then since it'll already be reconfigured to allow my CAS back there.

kinda a bugger that i now have two very good choices of engines to pick from though getting rid of HLA clatter forever as well as gaining a better crank/head/oil pump is very tempting.

I definately can't wait to get rid of the HLAs. I will be using an nb6 engine whenever it is I get around to doing a motor up oneday.

Compression test booked in for my current original engine next Thurs. That'll be interesting to find out the results. Shame my regular mechanic can't do engine swaps at the place he works for, too big of a job & my other mechanic works alone so don't think he'd want to tackle such a job but have another nearby place in mind already.

Well what do I need in preparation for a swap? looking through mx5parts.co.uk,

*engine mounts (how many is needed?),
*silicone hoses kit for early 1.6L,
*inlet/exhaust gaskets,
*valve cover gasket


*engine rear oil seal?