Did Baz happen to tell you why you leave the exhaust port at 35mm and not oversize it?
Would like to know as i have an a87 head with 44mm inlet and 35mm exhaust which will most likely be going on an L16 Block with 87.5mm pistons.

Ive spoken to baz at datsport about a similar thing. I also need to use a L16 to make thing easier with rego. Im doing a bored L16 with L18 rods, hi comp pistons and a87 head. I was told to make the inlet valve to 44mm and port the inlet port and concentrate on the valve side of the port. Also to leave the exhaust valve. Even reading up on L series race engines the exhaust valve always stayed at 35mm. Also use a 200b exhaust manifold not extractors. U xan get a sss manifold take the hitachis of port the manifold to I think 44mm again and pommy 4 studed su's fit perfectly on an angle. Apparently they run fine like that. Also somthing about a L20b cam retarded 4 degrees gives sss cam timing. I was trying to remember to much by then lol

If I remember correctly Stanza L16 rods are the ones to use as they have 9 mm rod bolts instead of 8 mm.

thinking of using L18 crank L16 rods 240z pistons .... thoughts

i use L18 cranks and pistons, with L16 rods. pistons are shaved flat.

a must for L enthusiast.

http://www.ozdat.com/ozdatonline/enginedesign/

Ps dont overcam your l series. I love to rev but find I loosevtoo much low and midrange for the street and hill climbs. Tracks different but if just using for street and hill climbs stick to a mild ish cam. Im using nla wade 733a currently.
tried a 72deg wade which was ok but not great in a low 3.7ratio geared stanza.

.

There are both 4 valve and 3 valve KA heads,but the real problem will be the bore size on top on all the usual mods needed.
Plus as you mentioned getting enough compression.

For road use on of the most successful L 16 heads I have modified was in fact an early L16 head with the 40 mm and 33 mm valve sizes simply match ported to a SS manifold, Superior gas speed Torque and throttle response compared to a Genuine SSS 219 casting.

The real head outside of an LZ twin cam or FIA head was the 219 SSS casting but fully modified needed at least 45 mm Weber's plus full port work Big valves 44 mm and 36 mm plus extractors Seton or FIA type plus all the bottom end work to match and really only worked well at over 11 to 1 Compression ratio.

Not an ideal street engine in any way, Port matching to a SSS manifold with a gradual taper in the ports to aid gas speed on the inlet side and a good cleanup and opening in the exhaust side to aid extraction add in chamber work to make sure all are equal in size as the basic design of the chamber works OK plus the appropriate compression ratio around 10 to 10.5 for the street should be good.

Flat Top 240 Z pistons (Do not rev over 7,000 on a regular basis without annual replacement unless forged) or what does work very well is to use an L18 crank and Rods to build a 1688 engine that makes good torque but revs very well with the lighter 83 mm 1600 sized bore compared to the L 18 85 mm size or bigger such as the 87 mm 40 thou oversized L 28 pistons which gives an 1855 capacity that to really benefit needs webers, cams, exhaust etc.

I was thinking of maybe doing a L16 conversion but was looking at making it a L18 by boring and using L18 rods and crank. Also wanted to kno if a ka24e head would fit but I think it lowers compression. But if theres a piston that will suit then I would go the ka head. 3 valve and more power. Does anybody know if the valves will clear the block if that makes sense?

hi all i have a L16 , and i have a L18 A87 closed chamber head. i intend to give the head a little port and polish. is this a good mod? and what else would you do or have done that works best.
thanks.