Yeah it looks like a L engine with pushrod version of the cylinder head (L-type block and L-type port layout). Appears to only be used by forklifts

The cam timing gear cover looks like A-series

Nissan K15 pistons

DD didnt even know the K15 engine existed! its not anywhere online that I could find

do you know the bore and stroke or any pictures of it as I can only find the k21 and k25

Its a good looking engine and revs to 3000 rpm for max hp and 1600 max torque maybe slugs
are not compatible for high rpm?

pistons are cheap
https://www.alibaba.com/product-detail ... 017115.156.54c81adb9Q2nYF

looks like a nice head too with alloy rocker cover standard
you could fill the top of the extended port area with weld
and port even higher than A series heads
http://www.k21engine-parts.co.uk/contents/media/l_11040-fy501a.jpg



awesome downdraft ports!!!!
https://www.youtube.com/watch?v=BOCLhFDhj6Q

Dave are the K15 pistons heavier? I seem to recall looking at forklift pistons years ago but they were heavy.

As for quench; on the two stroke bikes and my F500 it's one of the things that are checked when building a motor.

The original poster -- rallytwit -- is a seasoned racer. He is looking for flat-tops for A12A engine. He also stated twice that he doesn't want custom pistons, which those D16 pistons are

Unfortunately A10 pistons (73mm bore) won't fit the A12A engine (75mm bore)

In general flat-tops are more powerful than dish pistons given the same compression ratio. For example: 10:1 with dish and small combustion chambers make less power than 10:1 with flatties and medium combustion chambers. They can take more spark advance, return more power and more fuel economy, and are less prone to pinging detonation so can use lower octane fuel. See our tech article Quench

I'd look at Nissan K15 pistons -- off-the-shelf flat-tops, correct pin height and inexpensive. Look like A12 GX flat-tops but with 75.5mm bore

DD , I am confused.
What does flat tops offer besides shape ?? Isnt it the compression that counts ??

These high comp 11:1 D16 pistons have pin height 19mm length 137mm compression height of 30mm
and come in 75mm/ 75.5/ 75.75/ 76

https://www.ebay.com.au/itm/NIPPON-RAC ... 9d4373:g:FWgAAOSwGvhT5REe

You can buy A10 flat tops 1.0 1.5 oversize here in Australia . Pretty sure their same size as A12 .
That might bring you upto 74 / 74.5 mm

http://www.swmotorsport.com.au/index.php?cPath=9_59

Toyota K series are usually heavy things
very much like L series 38mm comp height

If you ran 73.25 pistons and A14 crankshaft
it gets you under 1300cc and you can use
some pjz forgies he had for sale recently.
However you prob want revs rather than torque
There was a tall A13 that uses the 77mm stroke
as well which is a small bore A14 block

Will the K15 pistons work for you Tom? Nissan off-the-shelf flat-tops, correct pin height and inexpensive


A15 uses a different pin height than A12A

Vitara *dish* pistons are sometimes used to build a Honda D16 turbo motor

Honda D16 is 75mm bore. D16 piston compression heights vary from 27.4 to
30.7 (and rod length varies)
None have A14 spec pin-height
For an A15, the 30mm pin-height ones are D16Y7 (1994-1995 Civic Ex 1.6)
& D16Z6 (1992-1995 Civic Si 1.6). The piston total length is
longer than A15 piston

Unfortunately they are not flat-tops

If only going 76.5mm thats a good compromise.

Tom would you know if A series camshafts are
factory hollow units or just solid cast?

A few people on here say the Suzuki Vitara D16 turbo pistons fit straight in a A15.. I know they make a High Comp coated piston
11:1 for around $125 . Maybe something to investigate