D series questions

So I am starting to plan for a D16 build and I want to begin to gather parts. I am correct in thinking that is it early blocks with the late heads that increase the compression ratio right? Or is it the other way round? Also what head flows the best out of the D16 series? I heard a rumor that it was the Y7. How much better do aftermarket intake manifolds flow then the Y8 manifold (which I have heard is the best flowing of the stock manifolds)? Is it enough to be worth the money?

There's a few good combos. In general a VTEC head on a non-VTEC block is what you want to go for. When I was thinking about doing this, I wanted a D16Z6 head on top of a D16A6 block so I wouldn't have to convert to OBD-II

D-series.org is a good place to start gathering info. So is onecamonly

What car are you starting with? how comfortable are you with wiring?

if you looking for another compression bump p29 pistons will do the job also.

its generally accepted tha the edelbrock intake manifold flows the best but you need supporting mods (cam, high compression, minor port work) to really reach its potential. the skunk2 is also a good manifold. for oem the y8 manifold is refered to as the "type r manifold of d series"

as far as head design the z6 has better flow characteristics. the y8 on the other hand has a better combustion chamber design.

there is a great d series compression calculator that is just a google seach away also.

You want to stay away from the P29 pistons unless you have a DOHC ZC head. The other chambers are just too small, and benefit much more from a small-dome or flat-top piston with the head/block milled to get quench distances down to a minimum. For starting port work, look at cleaning up all the casting marks, gasket matching, and blending the bowls to match the valve seats but DO NOT touch the port floors at all.

You didn't mention if you want to go NA or forced induction.

If you're interested I have a DOHC ZC head. Shoot me a PM for more info.

you cannot easily bolt a DOHC zc head on a sohc block....

if you use a y8 head,you do NOT need toconvert to obd2, as the obd2 and 1 distributors output the exact same signal

fun fact= Y series engines have the SAME distributor bolt pattern as the obd0 engines! we have tuned vtec SOHCs with obd0 Turboedit software...splitime kinda pioneered it. using the AC output to signal vtec.

works.

redzcstandardhatch wrote: you cannot easily bolt a DOHC zc head on a sohc block.... if you use a y8 head,you do NOT need toconvert to obd2, as the obd2 and 1 distributors output the exact same signal fun fact= Y series engines have the SAME distributor bolt pattern as the obd0 engines! we have tuned vtec SOHCs with obd0 Turboedit software...splitime kinda pioneered it. using the AC output to signal vtec. works.

What he said. Whatever you do, I would stay away from the Y motor blocks and cranks. They seem to have severe oiling issues stemming from redesigned oil holes in the journals+a terrible oil pump casting design. It can be corrected, but it's a PITA

I may also have a full D16A1 (the DOHC D-series engine) swap I would sell you.

It would be going in a '96 Civic DX. It will be NA. I want to run street gas. I am just looking for a good bump in power. The car is OBD2. As far as cams, are there any hot OEM cams or should I just go aftermarket on that? This is just something I am planning for down the road. I am trying to get a plan so if I see the parts for cheap I can grab them. Is there any difference in swapping a DOHC D-series and a SOHC D-series?

Edit: Forget the cams. I am going aftermarket.

And also should I same with OBD2 or convert to something else? And what does that require wiring wise?

sobe_death wrote: You want to stay away from the P29 pistons unless you have a DOHC ZC head. The other chambers are just too small, and benefit much more from a small-dome or flat-top piston with the head/block milled to get quench distances down to a minimum.

I disagree. I've run a D16A6 with P29 (89 Integra) pistons, and loved the combo. It's the engine Honda should have put in the Si.

DILYSI Dave wrote: I disagree. I've run a D16A6 with P29 (89 Integra) pistons, and loved the combo. It's the engine Honda should have put in the Si.

What kind of compression does that give you?

Seems like I learn something new from every thread I read on this board. I love it.

jwdmotorsports wrote:

DILYSI Dave wrote: I disagree. I've run a D16A6 with P29 (89 Integra) pistons, and loved the combo. It's the engine Honda should have put in the Si.

What kind of compression does that give you?

11.1:1.

I'm not trying to knock that piston per say, because it is a very inexpensive piston for what you get.

The only other honda motor I would even consider using them in is something with an A6 head. The dome is just too tall and the wrong shape, plus the piston sits .040 in the hole, giving horrible squish as it compresses. This gave us fits when trying to tune it even with the head it was designed for; rediculous amounts of timing had to be pulled where it shouldn't have been necessary

I too once used the P29 (pm7) pistons in a turbocharged setup, but I was young and reckless. I'd take a small combustion chamber and flat piston any day of the week now.

I've got a buddy running the P29s in a build n/a Y8. Seems to work fine. The car is still slow as balls, but that's probably a product of weight rather than crappy motor. Seems to run ok. I still run circles around him in the stock Escort.

96DXCivic, convert to OBD1, it's easy. I'm pretty sure it's a matter of a jumper harness. Convert to OBD1 and then use one of the free tuning programs like Crome or something.

As for cams? No OEM hot cam. Junk2 makes some pretty decent cams. I believe they're "Stage 2" cam is an n/a cam. You can usually find them for pretty cheap.

So I am thinking a D16A6 block, Y8 head (or maybe a Y7 I heard a rumor they flow the best, I need to check that out), Edelbrock intake manifold, Skunk2 Stage 2 camshaft, OBD1 conversion. Should I go with P29 pistons in that setup or not? And also should I use B18A rods or just stick with stock rods?

Using a D-series compression calculator, the P29 pistons plus a Y8 head gives a compression ratio of 12.23:1. And P29 pistons plus a Y7 head gives a compression ratio of 11.69:1. How high a compression can I run on premium gas?

This is an n/a build?

You won't make enough power to bend the stock rods, so just use whatever is lightest.

Do you want to keep the VeeetaCK or not? Y7 is non-vtec, and i'm fairly sure you can't retro-fit the vtec stuff on it. So in that case, i'd go with the Y8. Honestly, just to keep it simple, i'd stay with the Y8 anyways, since even though i don't remember which way, the CFM difference between the Y7 and Y8 is like 3. 3cfm. Are you really that worried about it? I wouldn't be.

Here's what i would do:

D16A6 block
D16A6 crank
D16Y8 head
P29 pistons
D16A6 connecting rod D16Y8 head gasket

This will net you ~12.6:1 compression, and leave you a LITTLE room to deck your head 0.010" if needed, which would net you a nice even 13.0:1.

That's about the limit i would do on pump gas, unless you're interested in experimenting with E85.

96DXCivic wrote: Using a D-series compression calculator, the P29 pistons plus a Y8 head gives a compression ratio of 12.23:1. And P29 pistons plus a Y7 head gives a compression ratio of 11.69:1. How high a compression can I run on premium gas?

12.5:1 - 13.0:1 is about the max i would attempt on 92-93 octane, and be careful tuning.

I was going to do an aftermarket cam so VTEC doesn't matter to me. I figured the Y7 head would be cheaper.

What kind of hp can you expect to get out of an NA build with 13.1 compression?

jwdmotorsports wrote: What kind of hp can you expect to get out of an NA build with 13.1 compression?

Unfortunately the old adage of "N/A is the expensive way to go slow" is especially true on D-series motors.

You can expect 140-150whp depending on supporting modifications.

I figured if use basically stock parts the cost should be fairly low esp. if I am shopping around. If I was going turbo, what would I need to do different other vitara pistons?

96DXCivic wrote: I figured if use basically stock parts the cost should be fairly low esp. if I am shopping around. If I was going turbo, what would I need to do different other vitara pistons?

Vitara pistons may not be needed depending on your power goals.

But because you asked about them, i'll assume you'd be looking for more than the stock block can handle.

Vitara pistons
ARP head studs
Eagle H-Beams

Quick cheap and dirty.

N/A being cheap is relative. You won't get that 150whp mark on the cheap. That'll require a build head, more than just a cam.