Just out of curiosity.

Is it possible for the na/nb motors, to swap heads, and trannys?


I hear honda heads yap all day about how they swap different heads and trannys with different blocks and such.."b16, b20, single cam, w/LS head, GSR tranny, Typr-R this, bullshit that, and all honda noise"

Just wondering if its possible to swap such components with the miata motors..?

 

C'mon, guys. It was a valid question.

(lots of stuff deleted)


1: Transmissions are freely interchangeable between all year Miatas, as are complete longblocks. There are some electrical differences, but mechanically it works. Note that this holds true only for the NA and NB cars ('90-'05). The new style NC is a totally different vehicle, and nothing interchanges with those cars.

2: The 1.8 Miata engine isn't just an overbore of the 1.6, it's a totally different motor. The block is longer front-to-back, with a different bore spacing. So while certain parts are interchangeable (rods, flywheel / clutch, etc) the heads are not, nor are the cranks, cams, or manifolds.

3: Within the 1.8 engine family ('94-'05), most parts are interchangeable. There are only a couple of minor incompatibilities (eg: intake manifolds are not interchangeable across the 1998 barrier) but these are fairly inconsequential.

 

 

They will not interchange. You can swap complete motors but not the head/blocks. The only motor this works on is the BP and that would just be putting another head off a different year BP. Trans missions are interchangeable. Miatas are nothing like hondas for swaping parts. Trust me I own one of each.

 

Obviously, I haven't done this, but here is the book I was referencing:

Mazda Miata MX-5 Performance Projects by Keith Tanner. ISBN-13 978-0-7603-1620-7

Page 45: "Retrofitting a NB head on an NA Engine"

He states that ideally, you should use an NB intake manifold, but that you can modify an NA manifold. He suggest a head from a 1999-2000 based car as the most appropriate choice to avoid the VVT issues. He has suggestions for dealing with the CAS and VICS system.

Like I said, I haven't done it, but Keith has pictures that show it being done.

 

NB\NA as in 1.8 NA vs 1.8 NB

 

The NB head will fit onto a 1.8 NA engine ('94-'97) as the blocks are essentially identical. No 1.8 head (NA or NB) will fit onto a 1.6 ('90-'93) engine, which has a different block. The number of components that will interchange between a 1.6 and 1.8 engine is quite small, actually. Rods, bearings, lifters, flywheel (though the 1.8s got larger flywheels and clutches from the factory), a few other trivial bits.

Honestly, though, the gains to be had from doing so are relatively minuscule. And, these days, VVT is no longer something to be avoided, since several ECUs capable of dealing with it are available, plus of course the VVTuner, which is a neat little standalone VVT controller that also produces an NA-style CAS signal as a byproduct.

I just can't imagine why you'd go through the trouble. If you're going to do a swap (and presuming you don't want to go with forced induction), just grab the whole NB engine and plop it in. Higher compression.

 

Isn't there a 1.6 VVT head? Would that swap work?

 

Agree with all of the above. I was just quoting Mr. Tanner.

 

Not in the US market at least. VVT didn't come out until 8 years after the 1.6l Miata.

 

I have some conflicting information here.

Some sources say that the euro/Japan-spec 1.6L NBs continued to use the B6 engine.

Some sources say that at least some 1.6L euro/Japan-spec NBs had VVT.

I can find no evidence to support any B6 engine ever having been equipped with VVT.

Now, I'm no expect on the Z-series engine, however what little information I can find suggests that it was "based on" the B-series design, and that the block itself is either the same as or similar to the early (pre-B8) B-series block.

If true, then it's entirely possible that the head from a ZL-VE (a 1.5L engine with VVT) might fit onto a B6.

Personally, I think it'd be a waste of time and money.

 

or just retrofit a 1.8 vvt into the 1.6l head if possible, no idea if cam journals differ in size.
Would be interesting if you could fit it on both cams

 

Retrofitting a 1.6 motor with VVT would involve a huge amount of work. A 1.8 exhaust VVT retrofit would be less work, but still a ton of work.

 

So... All you guys are telling me that i could swap a 2005 engine in my 96 miata, and the transmission will fit?

 

yes.

 

Swap in a 12 valve Cummins turbo diesel...

 

Guys, I think loud miatas sound too ricey for me. So I think I am going to swap in a 2 stroke weed-whacker motor. That should help.

 

WOW Thanks, so i am going to swap 06 engine into my 94 miata

 

There is a difference between the 05 and 06 engine. A very big difference.

 

Yeah, they bored and stroked the 06 engine to 2 liters right