I'm planning on doing a complete overhaul on my D16A6: put on a z6 head, y8 main, port and polish, etc. While i've been collecting parts, I realized I would want to put in higher compression pistons. I came across some really nice ones for a JDM EG6 and was wondering if they were the right bore to fit into my A6 bottom end. Would it be a good idea to install them to increase my compression, or not? Thanks

here's the link:
http://www.hmotorsonline.com/shop/sc...age&item=10015

 

no those are b series pistons. those are 80mm and a d series bore is 75mm. you want to go with some pg6 pistons out of the dohc zc engine. you could also use some d16a1 pistons as well. those are plentiful in my area.

 

Would i be able to use the pistons for a dohc zc on my sohc zc? Are they interchangeable like that or not?
Would I be able to use P2P pistons from the Y8?

 

Yes, the dohc ZC pistons will fit the sohc. They're both D series.

 

personally i would use a6 pistons with a y8 head. right now i have pm3 pistons which are stock b2 pistons with a y7 head and im bordering 11:1 compression right now. what grade gas to you intend to run and what compression are you looking to achieve?

 

I actually have a Z6 head and am about to receive a Y8 manifold. Somewhere around ten : one in what i'm looking for. I know that the mini-me swap with the Z6 head will give me about 9.6:1 but i am looking for something higher than that.

Are you satisfied with the high compression from your pistons and head arrangement?

What about the P2P pistons from the Y8 block? Would they be a good choice?

 

yes quite frankly, the car has a lot more bottom end do to the compression. only thing that is wrong with the way i have my motor setup is its not tuned. im running a pr5 ecu from the more aggressive sohc zc out of the jdm integra. its runs pretty good with 87 octane. if i put 91 in it, i usually burn it pretty quick. i know chirping gears is pretty easy, but when you can do it in a untuned n/a 4 speed snap together as my dad calls it, its pretty fun. if i were to tune im sure it would perform a lot better and definitely get better than 23city/32highway.

as for p2p pistons, they could work, but if you can find a set of pg6 pistons like i stated earlier you would achieve your goal a lot faster. or you could have your head and block shaved and use a thinner head gasket to get the last little bit out of the compression and utilize the flat top a6 pistons as opposed to the slightly dished z6/y8 pistons.

 

So, if the pistons are almost the interchangeable, how would i actually be able to increase compression with dohc pg6 pistons? Are they domed to increase compression? Ridged? if not, then wouldn't it leave my compression ratio unaffected?

D16A1 is a dohc zc, so how are the pistons different?

Like i just don't know how they look, or if they would be different than the A6 ones i have now...