docmanakos

What would be the best D series short block, cylinder head swap? What cylinder heads can I get on a ZC SOHC VTEC or a D16A1 short block or any other D series short block with dome pistons? I am very interested in getting the compression up in the 11:1 range.

Stock ZC Block, Head, Head gasket, D16Z6 0.000 Deck Height 10.76:1 CR
Stock ZC Block, Head, D16Y8 Two layer Head gasket, 0.000 Deck Height 11.09:1 CR
Stock ZC Block, D16Z6 Head, D16Z6 Head gasket, 0.000 Deck Height 12.03:1 CR
Stock D16Z6 Block, Head, Head gasket, Deck Height, D15B7 piston 11.26:1 CR
Stock D16Z6 Block, Head, D16Y8 Two layer Head gasket , Deck Height, D15B7 piston, 11.63:1 CR
Stock D16A1 Block, D16Z6 Head, D16Z6 Head gasket, 0.020 Deck Height 12.77:1 CR
Stock D16A1 Block, D16Z6 Head, D16A6 Head gasket, 0.040 Deck Height 11.67:1 CR

Docmanakos@aol.com

tec_wiz

try running any d16 block with dohc zc pistons, and a z6 head with a 1.5 mm head gasket from apexi and you will be right around 11.5:1. running a standard y8 head gasket will net you around 12.5:1. the 11.5:1 wiith a good pnp, mani, pnp y8 mani, b-series tb, and full exhaust and intake with a crane stage 2 cam is supposed to net somewhere around 140-150 whp if done right and running good tuning.. of course, running 11.5:1 comp you will need good tuning anyways. check out d-series.org for more info.

docmanakos

try running any d16 block with dohc zc pistons, and a z6 head with a 1.5 mm head gasket from apexi and you will be right around 11.5:1. running a standard y8 head gasket will net you around 12.5:1. the 11.5:1 wiith a good pnp, mani, pnp y8 mani, b-series tb, and full exhaust and intake with a crane stage 2 cam is supposed to net somewhere around 140-150 whp if done right and running good tuning.. of course, running 11.5:1 comp you will need good tuning anyways. check out d-series.org for more info.

Wonderful information, thank you very much. I was looking to just buy another engine and just swap parts. I rebuilt my corvette engine with a high lift camshaft, increased stroke and I am not into doing another rebuild, at all. I increase the stroke, so I had to clearance the rods, then check valve clearance for the roller camshaft, etc, etc.

This engine is in my del sol and is an everyday driver, so I am interested in doing some internal boosting and leaving the rest stock looking. I'm only interested in the important stuff. Increase compression, cam shaft change, velocity port the intake runners, and extrune hone the intake manifold, etc. Port the exhaust runners, and manifold. Leaving the engine absolutely stock looking from the outside. I'm more concern with power at low and mid RPM, not so concern with top end increases.

v-6 hatch

i'm making 12.2 on my mini me with zc pistons on a z6 head

docmanakos

Which would be easier, going through all this switching or just buying a JMD used D16Z6 engine and going to the flat top (D15B7) piston and D16Y8 head gasket for a 11.6:1 compression or leave the Z6 head gasket and have a 11.26:1 compression? Basically how easy is it to just switch the pistons, do I have to pull the lower half and balance everything?

tec_wiz

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">Which would be easier, going through all this switching or just buying a JMD used D16Z6 engine and going to the flat top (D15B7) piston and D16Y8 head gasket for a 11.6:1 compression or leave the Z6 head gasket and have a 11.26:1 compression? Basically how easy is it to just switch the pistons, do I have to pull the lower half and balance everything?</TD></TR></TABLE>

it is ABSOLUTLY IMPOSSIBLE o use that combination. you can NOT use d15 pistons in a d16. I only yell to reiderate the fact that this cannot be done. this has to do with the diffrence in rod lengths in a d15 and the deck height of the block in a d15. If the d15 pistons were used the piston pin placement would move the piston up far enough to result in negative piston-to-deck height numbers. This wold involve the piston "popping" out of the block at TDC and hitting the head. If you are using a compression calculator you have to take into account for piston to deck height diffrences whenever using diffrent pistons in a block. This formula is

Deck Height - Compression Height (of piston) - Rod Length - stroke/2 = P2D height

check here if you need all this info. [LINK]http://www.knology.net/~jediklc/D.htm[/Link]

That is by far the best d-series compression calculator i have found. just play around a little bit to see what you can find. without using the zc pistons, I think the highest compression i could get was 10.8:1 and that was with a .5 mm head gasket. and remember to convert everything to inches in P2D heights and head gasket thickness's.


replacing the pistons is not hard, but then it's also not easy at the same time. you need certain tools that are just not comonly found in the home garage. such as a bolt stretch gauge for the rod bolts. If y replace the pistons then it's probably a good ideato replace the rings, rod bolts, and take a look at your crank bearings. If you have never torn an engine down before I would start with a spare you might have so you can see how everything goes. Although i recomend finding great instructions (haynes manual) that will take you through this one step at a time. If you feel this is beyond yur league, then a shop shouldn't charge more then 100-150 if you bring them the bottom end of your engine. It will be alot more if they have to remove the engine from the car. And if you do replace any bearings, make sure you gauge them correctly.

docmanakos

All my compression calculations have come from the knology site. I was looking to buy one of the JDM engines with about 30 K miles on it. I have a good friend who sells them here in New York so obviously the engine would be on an engine stand for the work. I assume that the lower end of the engine should be solid in that situation. So would you think that the easiest and possibly the cheapest and maybe trouble free situation would be to just change pistons on a D16Z6 engine? Instead of combining heads and short blocks. If a quick piston swap is the best all around move, what pistons would I install and would there be any issue to necessitate checking any clearances? Correct me if I'm wrong, but an increase of two points in compression would boast me nicely in the lower and midrange and a nicer set up for autocross?
I'm not to sure if I will bother doing this job myself, since I haven't done such a good job with my vette engine.

v-6 hatch

you'd want to get the pm7 or the p29 ( sae thing allmost) in abotu any blok they will yeild about 12:1 in my a6 i had liek 12.2 and they are chea i picked my last set up for 140 with rings brand new

tec_wiz

there is a diffrence between an a6 heads combustion chamber volume and the3 z6's chamber volume. using a stock head gasket you should get around 12.5:1 with zc or 88-89 teg pistons. using a thicker headgasket you can lower it how you like. try using the one off nopi.com that is stackable and is variable from .5mm to 1.8mm. using 1.4 mm you get 11.44:1 compression. and using the same block and head and just replacing the pistons is the easiest way i think.

I'm currently building a z6 with zc pistons and 1.4mm head gasket with pnp head and fully posrted IM, b16 tb, smsp header, and crower stage 2 cam with springs and retainers using uberdata. hoping to get around 140-150 whp.

egizzle8

Actually you are able to use the d16 pistons in a d15 block. You need to use the VX rods.

tec_wiz

that I have not looked into, probably a little more research and that might be a possible solution. although, once you find the rod length you will need to recalibrate your compression calculations.

v-6 hatch

tec wiz i' shoot in for a 155 whp before my itbs

crower stage 3 cam shaft
pnp head
rower retanaiers (stok springs)
pm7 pistons
skunk 2 intake anifold
smsp header 270 cc injetors
str fuel rail
acl bearings
omni high comp vavles
stock gs-r t-body
tuned on chrome and some where down the road itbs