I was looking at Wiseco's catalog, and it seems that they do not make a piston for a D16A6.

Would I just use a D16Z6 or Y8 piston?

Here's the piston list: http://www.wiseco.com/PDFs/Cat...a.pdf

 

Oh, someone must have put Wiseco's in an A6 before.

 

I'm assuming since the Z6 pistons are the bore size that I want, I should get those. I'm concerned about deck height and such though...

 

i bought y8 pistons i believe for my A6. the only difference between the z6 or y8 pistons in regards to using them in an a6 is the compression, one is higher than other but i cannot remmeber at this time. i got mine from b18bturbo.. pm him, im sure he can help you out.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tippyman &raquo;</TD></TR><TR><TD CLASS="quote">I'm assuming since the Z6 pistons are the bore size that I want, I should get those. I'm concerned about deck height and such though...</TD></TR></TABLE>

i havent used these so i have no good info for you. maybe some of the following will help though....

piston to deck height is listed in the info (and can be calculated)...it would be the same in the a6... the differences are in the combustion chamber volume...

z6 pistons:
ptod height = 0.18- mm (0.19 actual); 0.007 in (0.0075 actual)
-15.4cc dish
using the head gasket thickness they listed: 0.028 in
CR using z6 head: ~8.37:1
CR using a6 head: ~7.94:1

y8 pistons with a6 head:
ptod height = 0.84- mm (0.85 actual); 0.033 in (0.335 actual)
-14cc dish
using the head gasket thickness they listed: 0.028 in
CR using y8 head: ~8.41:1
CR using a6 head: ~7.76:1

so each piston will drop your static CR about a half a point when using the a6 head (hopefully my #s are right, i was in a hurry).
keep in mind the z6 pistons only come in a 20 over bore...

 

Thats close to VITARA compression,
Hmmmmm.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fastcrxsi90 &raquo;</TD></TR><TR><TD CLASS="quote">
z6 pistons:
ptod height = 0.18- mm (0.19 actual); 0.007 in (0.0075 actual)
-15.4cc dish
using the head gasket thickness they listed: 0.028 in
CR using z6 head: ~8.37:1
CR using a6 head: ~7.94:1</TD></TR></TABLE>

Can someone confirm that this is correct? Seems really low to me.

 

yeah they were really low when i figured it out too.

check this puppy out, bookmark it too.

http://www.zealautowerks.com/dseries.html

 

7.9:1 for the Z6's, and the Y8's are 7.71:1 According to that site.

Is 7.9 ok to run?

 

run a uber thin hg and you should make it back to 8:1 cr, which should be fine. 7.9:1 should be fine just boring out of boost

 

make sure youre taking into account the head and block getting decked.. thats an easy 20 thou. run an Y8 headgasket too. i checked, the $26 fel-pro hg from autozone crushes to .026 the same as the y8-2 layer. good for the budget guys.

 

Well, I think that proper tuning in vac will help with the gutless-ness out of boost.

 

have you takled to b18bturbo yet? helpd me out w/ome questions i had..

idk if this helps but i was gonn use a z6 block a y8 head n a6 pistons i je told me that my compression was going to be 10.5-1 soooo ya

talk to b18bturbo 4 wiseco pistons... n btw i sugesst wiseco over ne other piston company...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Swipe’d &raquo;</TD></TR><TR><TD CLASS="quote">
talk to b18bturbo 4 wiseco pistons... n btw i sugesst wiseco over ne other piston company...</TD></TR></TABLE>

Yeah, That's why I want them ! They are awesome pistons, but the low comp is putting me off. All I gotta do is deck the block a little more though and I'm good to go.

 

I'm assuming you have a 75.5mm bore. Using a head & block that are decked .010" each and a 2-layer Y8 HG, you'll get ~7.97:1. IIRC stock DSM turbo's run 7.8-8:1 stock, so its not too low for a DD. If nothing else, it will let you run more boost & timing before running into issues.

BTW Wiseco FTW. I got mine for under $440 shipped from summitracing.com.

 

How strong is a 2-layer Y8 gasket though? I don't want it to blow out at 300 hp levels.

 

Well its really just the center layer removed. All that layer does is restrict coolant flow more near cyl #1 and less at #4 due to it heating up. If you look at the 3 layers, the top and bottom have the graphite coating and are bent (can't think of the right term) like a big concave washer. The center is uncoated stainless, and is perfectly flat. It really doesn't do much, but I'd rather have evenly cooled sleeves when running 2-3x the power over stock.