LZ18 or L18⋅R-4V CDI Ignition System...Datsun 120Y B210

Both the 120Y B210 LZ18 and the Turbo Violet runs a CDI ignition system with sparks administered through the original distributor system via plug cables albeit with electronic activation instead of contact points.

Later model LZs have gone for the distributor-less crank triggered ignition systems.

L14-4V and L18⋅R-4V Part 1

For interests and interested readers' sake only! :-)...I present this post.

The L18⋅R-4V bears possibly identical specs to my 120Y B210 LZ18!

All opinions are mine alone and should be taken with a grain of salt! :-)

Following on from my previous post of the Formula Pacific L14-4V the following are some details of the engines offered.

These all refer to the later version of what we call the Nissan 'LZ' series of engines. The 'LZ' prelabel are used by the western world in reference to this Nissan engine series. The earlier version of the cylinder head had the smooth camshaft cover. The cylinder head was cast as a single piece incorporating the camshaft bearing journals and tappet bores.

By later version, I mean the cylinder head version that comprises 3-layers much like Cosworth's BD series engines.

Top camshaft cover.

Picture above does not show the camshaft cover.

3-layers:

1) Cylinder head

2) Camshaft journals and tappet holder

3) Camshaft cover

Offered for sale...one time in our past! 70s and 80s...possibly ex-stock of parts ran out and stopped by early 90s.

Dowels and bore info.

The names of the later version of the 4-valve L series 4-cylinder engines were:

1) L14(4V) or L14-4V

2) L18R(4V) or L18⋅R-4V

Two bore sizes were offered for the L14(4V) while the L18R(4V) had only one.

They grind cast finish of the L blocks to a smooth surface to help oil return to sump faster.

Enlarging radius of edges of the main bearing caps where it transitions onto bolt cap seating surface for stress concentration reduction.

Engine block oil/water gallery plugs and other mods for 4V head.

Interesting! Use of 'honing' plate. I can see it's more than 2 inches thick, possibly 3 inches or more.

I'm guessing the following:

1) Special honing sequence by cylinder numbers are given, 2-4-1-3 then 3-1-4-2.

2) Check of taper and roundness at depths of 20%, 60%, 100% in positions A and B.

3) Taper and out-of-round were not to exceed 0.02mm.

Engineers were serious about getting their bores round and straight cylindrically!

This seems to indicate the machining specs for depth and cylindrical recess diameter at the top for installation of the Nismo Z-ring/Gasket combo.

Also shown is the deck flatness tolerance of 0.03mm max measured with a straight edge in that manner.

Lastly bottom shows a breather piece install spec.

Formula Pacific L14-4V engine, An old brochure back when one could still buy it!

The following are the 10 pages of a very old Japanese brochure back when the L14 Formula Pacific engine could be purchased new.


Brochure was copied for me by a warm and friendly Australian Nissan Motorsports parts supply shop back in the 1990s when I had enquired for LZ parts with them. By then, this engine was already of historical value and the best they could do for me was this brochure :-)!

There are many precious bits of history and information that one could glean from these pages by looking closely.

I have uploaded these elsewhere but just in case you, the reader, haven't seen it.


Only for the Nissan racing engine enthusiasts would the following pages be of any value :-).


Clicking on the photo will bring up a clearer view if needed.

Yummy option of both downdraught and sidedraught Webers! Even when the Solex/Mikuni were the favourite Japanese equivalent at that time.

Z-Ring seal/gasket combo used then.

Nismo Sealing Ring/Gasket....160J Violet Turbo and 120Y B210 LZ18(4V)

There is only one thing about owning a Nissan LZ18(4V) engine today and that is the lack of off the shelf parts. Fortunately, the resourceful owners of today can get most items custom made albeit at a higher cost. Some performance parts can still be sourced from Japan for the L-series that is suitable for the LZ.

A bit of history (Wikipedia would have more...):

There is another famous engine that was the inspiration for the Nissan LZ18 and it is the Cosworth FVA which eventually found initial production life on the Ford Kent 1600 block of the 711M later type as the belt driven BDA in the forever loved and most famous Ford RS1600 of 1970. This BD series with the A replaced alphabetically by B,C,D,E,F,G,H,J,M,N,R,T,T-E, etc by ensuing later types were developed till the late 1990s.

One could still, today in 2015, buy parts for the BDA, BDR, BDM, BDG, etc off the store shelf in the UK brand new!! This being a purpose made racing engine that started life from the late 60s!

One such important part is the cylinder head gasket of the right thickness and bore diameter.

No longer available in 2015 are the Nismo sealing ring/gasket combination used for the L series engines back in the 70s and 80s. I had a set of 4 brand new Z-shaped cross-section rings as spare with 2 set of the L inline 4 gaskets of thickness 1.2mm. Today, in 2015, I would attempt to find a good used L18 block and have it prepped without sealing rings but instead I would use Kameari's L4 metal head gasket of t=1.5mm and bore 90.5mm. The use of L inline four gasket requires cutting the chain cover portion to extend it out for the LZ due to the extra layer of gear plate.

For the 160J Violet Turbo:

Now I know that the t=1.5 designates head gasket thickness....Not boost as initially thought. This LZ18(earlier model) turbo engine did have a shallower groove for the sealing rings and an asbestos gasket thickness of 1.5mm.

For the 120Y B210 LZ18(4V):

For the Datsun 120Y's later type LZ18(4V) engine, head gasket thickness was measured at 1.2mm. Cylinder head was taken off one time for servicing in Australia.

Engine details Part 2: An instruction manual of a normally aspirated LZ18 of relevance to the 1974 Datsun 160J SSS KP710 Violet Turbo

In my searching around for more information, in the earlier years after acquiring the Datsun Violet Turbo, I came across this instruction manual for an LZ18 from Australia that has important relevant information for the turbocharged version of the LZ18.

This was LZ18 #32, a normally aspirated version.

The information contained in it is self revealing to all the interested enthusiasts, engineers and mechanics among us.

I present to you...

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5