Should i bore an A12 engine and put A14 pistons in it??? Thanks

I dont think you could overbore the A12 block to fit the A14 pistons..

Because i think the A14 is bored out and has same stroke as A12..But the A15 has differnt stroke all together :)

Id say go with a A15

yes,you can overbore the block to 76 mm easily,but it'll only give you about 1270 cc's.you used to be able to get factory pistons at 76.85 mm which gave 1298 cc's.this was good for an under 1300 cc race car.the a14 not only has a bigger bore,but a longer stroke to get the 1390 cc's.you also have to bore out the litle ends of the conrods to accept the bigger gudgeon pins.i feel it's a good way to get more performance out of the motor,if you can't just get an a14 or a15.

I dont wanna go to all the trouble to fit a A14 or A15 in my Datsun 1000. I want my car to be fairly fast but still be economical enough to use daily. So i only want to probably put 1300 pistons in it. Or maybe even not. Please give me a good idea to easily gain a little bit of power for an A12 in my 1000. PS A guy told me a Sunny 5 speed gearbox might bolt straight in to an A12 is this true. Thanks

yes then,bore it to 76 mm,give it a mild cam,a good exhaust,& tune the carb to suit,& it'll be great.if you can find an overdrive 5 speed,it'll go behind the a12,you'll just have to fabricate a gearbox mount & clearance (that means bash it with a hammer) the transmission tunnel.

Thanks but what pistons would i put in it. Cant wait to build it Will send some photos when i get a digital camera

Dude,give ACL Engine Parts a call.
Their in 87 Mitchell St,Maidstone,VIC3012.
Don`t know their Website but I`m sure they will help you.
I can`t find any of my old piston books, must have misplaced them.
Good Luck!

OK blokes, here's the good oil for the Datsun 1000.
I have had a 1200 engine in my '68 sedan for over 20 years.
Use the early 1200 engine & it will go straight into the chassis. I used the 1000 engine mount brackets & sump for a perfect conversion. Use the B10 [1000 model] altenator & bracket, including block mounting hardware for a true bolt in.

I bored mine to 76mm & drove it so much that i eventually wore it out. Use the A14 pistons & have the reconditioner bore the rods to accept the larger wrist pin that these 76mm pistons use. They might have a grizzle about that, but they should do it anyway.
This replicates the A13 engine that we never saw here, but i think that the US did.

Next i bored it out to the first oversize which brings it up to 76.5mm. The engine is still under 1300cc, but only just. I have worn it out again. For street use, you should be safe at 77mm which is the second oversize for the A14. We have one engine at this bore size running around here now without problems.
I will go for broke with mine & i will be installing "A" class sleves & run third oversize pistons of 77.5mm. The finished engine will end up at about 1453cc with a few extra tricks & a bit of money, but HEY, it's only a 1200. See, the engine number is prefixed A12. ALL of this will be achieved with STOCK Datsun parts, you just got to know WHICH parts.
This engine is going into my KB10 [1000] coupe. Please remember that the stock type carb & aircleaner will rub on the underside of the bonnet, so try to use sidedraught induction. My setup is 1200GX, which is what the whole engine is.

You will quickly find that you will need to install the 1200 diff center as the extra power will make it feel like you need an extra gear, & while you are at it, you may as well use the 1200 gearbox as well & your speedo will run truer than with the 1000 box. Get a ute box if you are going to use a 4 speed as these have a more satisfactory front bearing for the cluster, which may be important if you plan on "working it hard"
Chris
P.S.
The A13, the A14, & the A15 all used the 76mm bore size, but used 70mm, 77mm, & 82mm strokes to get their diferent capacities, & with each increase in stroke, the block was made taller, which is why the air cleaner rubs under the 1000 bonnet. The only exception was the A15 which was the same deck height as the A14, but used shorter pistons to accomodate the extra 5mm of stroke.
Happy Datsun 1000 driving. Its a great car, & with an "improved performance" 1200 engine, it's a great combo.

If you want to go to 1270 you can use A12a + .04 inch pistons and not have to deal with the making the A14 pistons fit your rods.

My question is are flat top pistons better and how much would they raise compression without cutting the deck?

What is the best source ( where can I find them) of A12a flat top pistons?


dog.

Thanks DODGEMAN for all the info. Was your engine for racing or for daily driving?
You had an A12 running for 20 YEARS thats a great engine. WHO needs rotary or CA18DET (not that would fit in a 1000)

Thanks
PS Im sure ill start an argument with that