Are these heads ported?

[adam quantrill]

Well to me they look a little gas flowed, possibly. What do you think? It turns out to be an NCK engine:






Also what's the little dink machined into the head chamber? - is it to match the volume precisely on a per-cylinder basis? Each dink is a different size.



And - last of all - do these piston cut-outs mean I can use a higher-lift cam? Or what?

[jon haines]

They defo look different to my heads on my 350 adam. the first picture looks more confincing than the second, cant help with the other points.

[pistolar]

My old 400se had ports like yours.
I bought a new pair of stage 3 or 4 for it and when they arrived the ports were nowhere near as big as the originals so i spent a fortune having them reworked.

[adam quantrill]

Cheers chaps notice the valve stems too?

So I guess you would call these stage 1 heads?

[chapperssx]

Hi Adam measure your valves it may shine some light as to what stage heads you have ! To give you a referance here's some info on the differant stages JE Develoment provide.. http://www.johnealesroverv8.co.uk/19.html

[mrzigazaga]

Hi Adam..Maybe the compression has been lowered in the heads to eliminate any detonation, Especially with a supercharged engine..I have had this done to the unleaded heads that are being fitted next week to mine..The compression volumes must be equal..I believe when its worked it has a perspex sheet that fits flush on the head and then fluid is injected through a tiny hole in the perspex to measure the capacity of each combustion chamber....Ziga

[adam quantrill]

Yes forgot to mention when I cracked the heads off (pun intended!) there were already composite gaskets under there, which reduce the CR anyway by about 0.5.

Yes good idea I'll measure the valve diameters and compare.

[jmorgan]

Still have my old heads that were supposed to be stage 3. Water jacket split (over ported). Be interesting to measure a few things on them, funnily enough the car is in the proper garage having some work done and I can fish them out as I am painting my garage floor whilst it is away. Have to fight the spiders off first.

[adam quantrill]

Measured valve diameters - seem like standard 40mm inlet 35mm exhaust.

Also the valve lift is around 10mm with the current cam and no oil pressure in the lifters.