bloody watepumps!

Just in case nothing works out for a mechanical waterpump setup

Ive been thinking there is an alternative
The 75.3mm bore z5 engine in some markets
has a chain that ties both cams internally.
In fact all Z heads have the chain provision
on the head design so any chain cogs can be
pressed on to fit other Z cams then the chain
can secure them so just one belt pulley can run.

Externally just one timing pulley belt drive
on the inlet camshaft which is the opposite
side of the waterpump would allow plenty
of clearance to use the stock A series w/p.

All the Z heads average around 110-132hp for 1.5L
top of the range models which is a really nice
upgrade over any ohv 8v head worked or not.

The smaller ZL-VE pulley and crank cog can be used which
are smaller than the B series and has the option of
variable valve timing on the intake cam (S-VT)

I have that Z5 head sitting on my shelf.

Single timing belt drive pulley to drive the intake cam, and a chain to drive the exhaust cam.

now that is getting fancy!

Not sure on the availability of that head in particular, but the B6 is common as muck. Thats a better option.
Plus Ill have to admit - if you make it suit that head, then it wont be any good to me! Arrgh.... Im neck deep in the B6 head setup.

However, that does sound very cool and fancy pants. VVT options and all.

I can make the plate accommodate both heads really.

Just a matter of having an idler mount point left vacant.

I picked up a head from a late model ford laser with the B6 for not much.
the Fourth generation (KJ/KL/KM; 1994–1998) laser also ran with a B6 and apparently has 'roller rockers' of sorts.
the Fifth generation (KN/KQ; 1998–2007) has the ZM-de engine you speak of as well.

https://en.wikipedia.org/wiki/Ford_Laser

I haven't done anything with the head yet. Its still as grotty as the day I picked it up. Ill clean it up this week and take some photos of that one as well - It might be an easier option / supply of the B6 head.

Not that it matters much to me - im still going with my early KC laser head as ive already done all the work to it- but it may yield some good info / options for others

Apart from a few water passages these heads interchange pattern
even camshafts are a direct swap on each other etc on the b6.
The special B6 head was B6-ZE (RS) but only made 120 hp (90 kW)
whilst the 1.5 L ZL-VE made 130 hp (97 kW; 132 PS) !!!

Z engine share the same bore and stroke as the previous gen B6.

The Z series head was an evolution of the BP-Z3 engine on the turbo mx-5 SP

So the 1.5L Z made more NA HP than any B series naturally aspirated head even 1.8!

is it the valve angle and port size that is slightly different?

For the ZL-VE head...yes correct yet even the last b6 RS had
raised ports and S-VT as well but had Z had the more efficient
shallow style efficient combustion shape found on motorbikes.

There is even more potential with slightly worked ZL-VE cams,
40mm bike carbs, headers and valve springs for 8000rpm.
An A15 bottom end with 78mm ZL-VE pistons and H beam rods
will have extra A15 stroke, CCs & higher possible redline
to achieve that power with reprofiled cams.

Funnily the 1.5L has 78.4mm stroke the 1.6L 83.4mm which
are very close to the A14 and A15 etc.

The weight difference of the Z head is also amazing due to
its narrower valve angles, quoted 15% lighter by the same
guy that was doing the B6 and ZM hybrid below.

The good news is, both heads will work with same plate
so more option for heads at least for all interested.

That's the Z head with dual cam pulleys?

To also let everyone not wanting to do a DOHC setup I can also make a version where we can convert to a HTD timing belt system and do away with the chain.