ok guys, i've had a look around, but can't really find too much... so in my build thread i've outlined that while i'm replacing the headgasket, i'm looking to do some head work to my A12...

what i'm looking for is no dyno queen HP monster (lol said in the same sentance as "a12") i just want to liven up the car, and make it less of a struggle to pull itself around...

that being said i do enjoy taking it out for a good hiding around the hills, and plan on some major suspension work in the very near future... so having some good power, and great response is high on my lists! but i am realistic about it, if i wanted real power i'd obviously do an engine swap, but for this car it's important for me to keep with an A series... i just like the idea of a free revving A12, even if the power isn't anything to rave about


so far the car is getting a new cam, ported heads, larger valves, port matching etc, obviously extractors/exhaust, and intake are high on the priorities, but i'm wanting to go a different path to the typical webbers etc... i'm thinking bike carbs may be a good option like mikuni's off a GSXR, but off which size? you hear of guys pinching them off the 1100, but do the 750's run the same carbs, just different jetting etc?

headers is another one, i like the idea of going with something less common, but spending the $3500 on a set of tomeis doesn't excite me... well it does but it doesn't excite the missus... lol what else is out there?

any specific work i should be looking into with the heads? any specific cam grinds? what else should i be looking into? i want to keep a stock bottom end in it, at least for the current build...

so, any and all advice is welcomed!

Might sound a bit drastic, but you're pulling the motor out to change the cam, so - I saw on E-Bay a set of stock A10 pistons which are the same diameter as A12's. From what I can remember, these are flattops. So, instant compression raise, for more torque. The heads off, you're pulling the sump off to get the lifters out & radius'd, so taking the rods & pistons out isn't that much more work. If it wasn't E-Bay, it was Gumtree. That with the cam & the head work should wake it up. Whether you'd need to change the bearings at the same time is up to you, but it's something else you can do to make the engine last a bit longer. Old wives tale is you need to do both at the same time, or the bearings'll fail, but we're not talking about an old holden motor, we're talking about the way over-engineered A series.

http://www.ebay.com.au/itm/Nissan-Pisto ... 1e8b79ed87

Yes, it was in E-Bay, with an opening bid of $89 & $15 postage from Queensland, & they are 73mm flat top pistons with rings & gudgeon pins.

CCC, Comp, Cam and carbs. The A series respond well to a good cam upgrade. With a lift in compression and bike carbs, get a cam with more than 230@.050" duration. I have a very nice set of tig welded stainless pipes that will work well with a good set of bike carbs (they wont clear a webber manifold) that I would sell for the right project.

oh god those flat tops...

sadly my budget has already been completely blown out of the water, it started off as just a head gasket... and now it's this... funnily enough i kinda did the same thing with my daily driver, 5ltr VS caprice, leaky rear main seal, figured if the motor has to come out to do the rear main properly, might as well give her a freshen up, no point freshening up a stock stroke motor so might as well throw a stroker in... $10k and a LOT of trouble from the missus later i fixed my rear main seal...

so sadly the budget has been set in concrete, and we're not allowed to go over it... lol i figure if i can get a rock solid head, intake and exhaust package i'll be happy, then i can look into a bottom end rebuild down the track, because in reality i'd like to go quite silly with that, buold it for 10.000rpm, dry sump etc... so i'll live with the stock bottom end for now, even though i'm already so deep into it, so that down the track i can have the bottom end i really want...

well i went and saw my engine builder the day before yesterday, the head that was on there was badly cracked, so he has sourced an oval port head, and that is now getting what they consider the "full race port" as well as larger valves, full lifter/rocker setup... i didn't get the exact details, well i might have but i tend to forget things easily, especially when people talk fast lol

cam profile again i'm not sure on, but he was talking about having power come in around the 5,000rpm mark, with a grind that he referred to as very aggressive... so i'm hoping it should have a very nice little response to it...

have you got any pics of the headers? what sort of price would you be looking at for them...? i think i may still be able to swing the missus around for some headers... they ARE needed after all... lol

Power coming on at 5000rpm is not fun at all, been there
was a pig to drive on the street you had to be aggressive
all the time and got tiring very quickly.
Be careful of very aggressive cams that are like a laggy
turbo motor over a torquey motor with some zing.

Go for a cam that works from 3-7k instead

I have a GX A12 bottom end that just needs a honing and rings
thats factory GX bottom end, GX cam and flat tops
If interested send me a pm