I am new to the sight and was wondering if anyone knew if there was a difference
between a d16z6 block and a d16a6 block everything I have found on the internet
has shown the same bore and stroke with different compression and head code
I am gathering that the only difference is in the heads can I use a d16a6 in place
of a d16z6 and will there be any performance losses???
thanks for any help

 

Forget the d series and built a b-series or if you have the $$$ go with a K series.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ssrkrew &raquo;</TD></TR><TR><TD CLASS="quote">Forget the d series and built a b-series or if you have the $$$ go with a K series.</TD></TR></TABLE>

Way to answer the question

D-Series in general have the same bore of 75mm. There are differences between the two engines, mainly that the Z6 is VTEC and the A6 is not. Swapping heads between the two will change the compression ratio because (generally speaking) the older A6 has a lower compression height piston while the newer Z6 has a higher compression height piston. You would also have to take into account the difference(s) in the combustion chamber volumes as well as the volume of the pistons themselves (dish/dome/valve reliefs).

Also, generally speaking the D-Series heads are interchangeable so you can put an A6 head on a Z6 block (and vice versa AKA Mini-Me). Is that your plan? To use an A6 head on a Z6 block? And why would you want to do that?

 

^^ correct...

what are your final goals out of the set up in question?

if you are going with a basic set up just do a Z6 or your going all out it wouldnt matter because by eby evtec and full lock on your cam

 

The d16a6 blocks have steel main caps, if the d16z6 doesn't that would make the a6 block better imo.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 24TEN &raquo;</TD></TR><TR><TD CLASS="quote">

Way to answer the question

D-Series in general have the same bore of 75mm. There are differences between the two engines, mainly that the Z6 is VTEC and the A6 is not. Swapping heads between the two will change the compression ratio because (generally speaking) the older A6 has a lower compression height piston while the newer Z6 has a higher compression height piston. You would also have to take into account the difference(s) in the combustion chamber volumes as well as the volume of the pistons themselves (dish/dome/valve reliefs).

Also, generally speaking the D-Series heads are interchangeable so you can put an A6 head on a Z6 block (and vice versa AKA Mini-Me). Is that your plan? To use an A6 head on a Z6 block? And why would you want to do that?</TD></TR></TABLE>

Thats not really what makes the difference. the .5mm difference in comp height is not the reason. The a6 (pm6) piston has a higher dome of -3.40 wile the z6 (p28) has a dome of -10.10.

Bottom line you put p28's in an a6 your compression goes down not up.

You get the jump in compression from less Combustion Chamber Volume (cc). The a6 combustion chamber has the most volume (38.00cc), thus giving it the least compression. The z6 combustion chamber has less volume (34.60cc) giving it .04 higher compression in stock form than the a6 even though it has the piston with less dome cc's than the a6. It also has a thinner headgasket than the a6.


<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by S2R Honda &raquo;</TD></TR><TR><TD CLASS="quote">The d16a6 blocks have steel main caps, if the d16z6 doesn't that would make the a6 block better imo.</TD></TR></TABLE>

I agree.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by spun Vtec &raquo;</TD></TR><TR><TD CLASS="quote">

Thats not really what makes the difference. the .5mm difference in comp height is not the reason. The a6 (pm6) piston has a higher dome of -3.40 wile the z6 (p28) has a dome of -10.10.</TD></TR></TABLE>


Hence why I said:

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 24TEN &raquo;</TD></TR><TR><TD CLASS="quote">
You would also have to take into account the difference(s) in the combustion chamber volumes as well as the volume of the pistons themselves (dish/dome/valve reliefs).</TD></TR></TABLE>


Given that both the A6 and Z6 have similar compression ratios, I thought it would be a given that because their respective pistons have different compression heights/volumes it would be easy to see that the volume of the combustion chambers would have to compensate respectively in order to maintain that similar compression ratio. In short, higher compression height piston+volume of the piston+greater volume combustion chamber=lower compression height piston+volume of the piston+lower volume combustion chamber in the case of the A6 vs Z6 compression ratio (not exact measurements obviously, but 9.1 vs 9.2). I guess I shouldn't have assumed.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by spun Vtec &raquo;</TD></TR><TR><TD CLASS="quote">
Bottom line you put p28's in an a6 your compression goes down not up.</TD></TR></TABLE>

I don't recall anyone mentioning swapping pistons, just heads (but you are right one in that piece of info ).

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by spun Vtec &raquo;</TD></TR><TR><TD CLASS="quote">
You get the jump in compression from less Combustion Chamber Volume (cc). The a6 combustion chamber has the most volume (38.00cc), thus giving it the least compression. The z6 combustion chamber has less volume (34.60cc) giving it .04 higher compression in stock form than the a6 even though it has the piston with less dome cc's than the a6. It also has a thinner headgasket than the a6.</TD></TR></TABLE>


Same point I was making, I guess I shouldn't have assumed that people would make that connection.

 

Right. My point is, compression height dosnt mean anything without factoring in the dome.

Case in point the pm6 (a6) piston yeilds a higher compression in any combo over the p28 (z6) with less compression height due to more dome cc.

 

here is what is going on the z6 was built low compression to begin with for a
turbo it was in for 5 months or so and the thrust bearing went out this is a standard
transmission and all the spects were good when I built the engine the block is
damaged from the thrust bearing I have an a block and crank that I would like
to use with the set up i currently have there is no damage to the head or the
rods or pistons, I wanted to get new rings and bearings and build the a block to
put in place of the z block using the v-tech head. from what I see it will work
compression is not going to change considerably with the dish pistons that are
already in the z block if this is correct and it will work in place of the z block please
let me know I appreciate all of the help

 

Yes the blocks are interchangeable. The mounts may not line up perfect depending on your chassis but it will still work.

Make sure you take out the oil plug if your putting a vtec head on a non vtec block. (the plug is acessable when the head is off, its on the intake side of the deck of the block in the middle. It comes out with a small pick)

 

i rather stick with the a6 for a all motor build than the z6. plus if the z6 was a better platform for all motor why doesn't bisi use one hmmmm i wonder why. lol plus vtec is overrated in a single cam engine unless you plan on saving gas but in a all motor sohc you kinda throw that away.

 

The a6 head is supposed to have a better port arrangement than the vtec heads.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 661rex89si &raquo;</TD></TR><TR><TD CLASS="quote">i rather stick with the a6 for a all motor build than the z6. plus if the z6 was a better platform for all motor why doesn't bisi use one hmmmm i wonder why. lol plus vtec is overrated in a single cam engine unless you plan on saving gas but in a all motor sohc you kinda throw that away.

</TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by S2R Honda &raquo;</TD></TR><TR><TD CLASS="quote">The a6 head is supposed to have a better port arrangement than the vtec heads.</TD></TR></TABLE>

Did you guys read the OP? he's asking about the block's

The factor that the a6 head flows a little better almost never comes into play. If he's building a drag car or shooting for record numbers then or sending his head away for $$1-2k portwork, valvework then i see yourpoint.

The main reason bisi didnt use the vtec head was because In case you forgot bisi runs carbs. Vtec and carbs dont mix. Also There are more moving parts.


plenty of people have put down awsome numbers with a z6 setup. acually you can make more power with less money with a z6. The people putting down 180whp's with the a6's are running carbs and any dcoe setup is going to cost at least $$2-3k to get in and running.

 

thank you spunvtec I appreciate all of the help I am using a vtec head and will
remove the plug I know exactly what you are talking about, you have been a great
help with a direct answer. I have alot of machine work ahead of me to clear the
bigger rods and to pin the cylenders I figure you know what I mean about pining
the cylenders thanks again

 

good thread, tag for later. I'm in the middle of EXACTLY the same thing, right now.

(start quick thread hi-jack), but it relates

I plan to run the A6 block with Z6 head (it's what I have avaialable), but want to get my compression up to just short of not being able to work on 93 octane local gas. What is that, around 10:1? Ideas on the best solutions for that scenario? I'm ordering pistons and rods sometime this week.