Piston and rod size of the D14A3/A4/Z1/Z2

[Dodo Bizar]

When you want to upgrade the pistons and or rods of a D14 little is known about the exact specs inside those engines. Therfore a few years ago I bought a spare D14A4 block myself that was in bad shape and took it apart.

It seems the rod is very similar to the older D13B2 rods for which aftermarket rods are available.

These are my measurements which lack accuracy (possible errors of 0.5 mm):
-center to center length: 138 mm
-big-end bore: 43 mm
-piston pin: probably 19 mm (though my measurement readed ~18)
-compression height: 29.5 mm
-dish shape estimated between -2.8 and -3.3 cc

Click links for some pictures:
http://www.dodo-upgrades.nl/d14a4pistonandrod.JPG

http://www.dodo-upgrades.nl/D14A4piston1.JPG

http://www.dodo-upgrades.nl/D14A4piston2.JPG

[Law_]

On this site i'm trying to calculate the compression gain on the Head Swap for the D16Y8 one but there are too many data that it dont know like the Head Gasket thickness and elevation but i will make it

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

Other Good site :
http://en.wikipedia.org/wiki/Honda_D_engine

Cheers

[Law_]

what are the marks on the piston top?
Detonation marks?

also, ive been trying to calculate the compression for my Setup
Here are the values i've used on the site i've quoted before.

Block : Other
Cranck : Other
Bore : 75mm
Stroke : 79mm
Deck Height : 202mm
(i've invented this based on the difference of the D16 - D15)

Head : D16Y8
Combustion Chamber volume : 32.8cc
Piston : Other
Dome : -3cc
Comp. Height : 29.5mm

Headgasket Thickness : D16Y8
Thickness : 0.037 in

Maximum Operating RPM : 7500

Elevation : 3 feet (1m)

Result is 20 : 1

[Dodo Bizar]

Deck height is equal to D15B7 . I assume this since the D15Z3 and Z6 with same types of head also have the 103 teeth timing belt.

And deck heigt should be 207.45 approximatly, not 207 as mentioned on Zeal. Entering those numbers gives 9.76. I fiddled with dish size, around -2 I got 9.5 CR from it. Putting it to -3 gives just 9.3. So I think my guess on the dish size is the most discutable one.

About the piston, it came from an oil consuming car (just 200.000 ). You'll see tons of carbon deposits. The blank spot you see is probably blasted clean by the spark... but definitly no detonation hehe.

I can make some pics of a detonated cyl head, gives some idea...

[Law_]

Great. I would like to see. Cheers

[hondaNickx]

Piston dish of the P3Y (D14a4/a3 piston) is -5.4cc i've cc'd it with a pipet several times before.I can garantee it's correct.Deck height is 207 mm you can calculate it...

Stroke /2 = 79 /2 = 39.5
+
Rod length = 138mm
+
piston Compression height = 29.5mm
= 207mm

Piston is Zero with the deck so this is correct.Pistons Pin is 19mm btw

Zeal is correct with the numbers the only thing that isn't correct it the Head gasket thickness.They need to change that and put in Compressed thickness.Stock D14 HG is 0.028" compressed.D16y8 piston compression height is 29.3mm not 29.5mm like stated before .The dish is also not around -3cc but closer around -6cc.I'm also not sure that a Y8 pistons is zero with the deck.

[Dodo Bizar]

This is cool info Nick!

So with this info I should be able to pick my future piston without any doubts, which I still had till today. Could we actually get those numbers in most of the calculators out there? So are some people able to contact the calculator peepz and get themto stuff in the D14 numbers?

Now I will recalculate some stuff... one last very important question. Did you get out piston weight of P3X/Y? Or put it differently. Right now on stock block I get up to 8100 rpm, but I would really like to do safely 9000 rpm. By getting lighter pistons I should be able to safely get to these rpms can't I? Or do I need to change the rod as well for that? My head should be able to do safely 10.000 rpm right now... at least is the claim from Skunk2.

Hey wait a sec... we should also be able to inversely calculate the combustion chamber volume of the D14... gonna do some number crunching now.

[Dodo Bizar]

Okay, putting all these numbers into a calculator (I use Solblu -> http://www.knology.net/~jediklc/D.htm), and I always thought the D16Z6 head should be identical to D14 gives CR of 9.08. Tuning combustion chamber volume down from 34.6cc to 34 cc gives me CR of 9.20. So I guess that is my starting point for the D14 OEM block.

Now recalculate towards my D16Y8 head swap gives... CR of just 9.44. Not 9.5~9.6 as I always predicted... not that I really bother. But cool. Nice to know.

[hondaNickx]

The head volume is the same as the Y7 or Z6 head Joris.The calculator gives 9.09 CR and that's about right stock is 9.1 :1 .I use the Zeal calculator because you can alter more things like rod length and so and most people say that is the most correct out there.

You can compare the head casting numbers of the Y7 and the D14 head , they are identical in most cases . P2A-06

[Dodo Bizar]

You're right... all of a sudden I see 9.1 in all my documentation... thought 9.2. So ok, I have a bit over 9.5 CR right now. Yeah.

Head casting code I have to check... thought it was P2J... or is that EK3 and D16Y8 head only?