Hello guys,i have an a15 engine that is going to be rebuild to install in my 1200 coupe,so far i heard that the a15 head is not that good, will it be better to use an a14 head?
I'm planing to do the maximun porting and opening and polishing posible in the head;so if i'm going to do all this work in the head who will be a better candidate the a14 or the
a15?
thanks

The A15 was never meant to be a high HP motor from the factory. The stock rods and pistons are heavy, the heads were never up to par, and the stock A15 had less HP than the A12.
Do not waste money building inferior parts from the start, find a GX head and start there.

I have an A15 rebuilt as is the case with my dad. There is nothing wrong with the A15 head as it does have a good closed combustion chamber. Most of your porting should be done with the
exhaust because these engines need to breathe and breathe good. My engine has datsun 1600 exhaust valves but it is recommended that you take a nick out of the block and maybe even the
piston (depending on the lift) to allow the valve to move without danger. hope it has helped.
Glenn

The A15 heads are better than the GX head. because the A15 is a torqier motor it needs to breathe better so it had bigger valves
than the GX head.
i got my A15 head worked and i'm pulling a bit over 200hp at the flywheel with an Aseries injection manifold that i managed to find

What mods have you done to achieve over 200hp at the flywheel on an A15
engine?

-Andy

Where i am, i've actually got a guy who specialises in 1200's and A-series motors. i've got an A-series injection manifold with commodore computers and an Autronic computer, i've got ACL
dome top pistons to up the compression, the crank and rods are the stock units coz they are pretty strong, i've got my 1500 head which has been fully ported and polished and shaved to up
the compression again,the manifolds have been match ported, its got a set of Nismo stainless valves and seats, double vale springs, electronic ignition, cold air induction, hurricane
headers with a 2 1/4 inch exhaust. i havent had it on a chassis dyno yet to see what the power at wheels is

Justin

could u tell me the difference then with the gx head and a15,,, i just pulled a head of a jap import a15, it had large oval ports, large valves, headers with approx 1 7/8inch
outlet, single valve springs,, i fitted it to my 1200 in a my sunny, 13 inch wheels, and is boring, but with same combo in my 1200 ute with a14, 14 inch wheels, it flies, i know the
sunny is 300kgs heavier, all carb jetting has been done etc ????? ute has extractors?? just wondering,,, buzzard

May be the ute combo of 300kgs lighter and lower diff @ 4.1 vs the
Sunny @ 3.9?

another thing i did do, compressin test, ute 220psi w/- a14 shaved head oval ports on a14, and sunny 170psi w/- a15 shaved head same amount on a12 with dished pistons, i
cant remember the amount of dish on 1400 pistons, both cars rev at same speeds same amount, 80km 2nd, 130kmh 3rd. 300kgs would make this much difference? thanks
teratonga,kool,,,,,,,,buzzard

shadow69181,

With your A-series fuel injection manifold, are you using the stock throttle body (twin butterflies) and injectors? The A-15 I'm building will be very similiarly equipped as far as
the cylinder head, except I'll be using low compression forged pistons and turbocharging it. I would love to get 200hp out of my engine when it's done which shouldn't be very hard
with a turbo. The only thing I'm worried about is the clutch and driveline holding up!