MASSIVE D18Y8 Head Onto D15B7/8 Block MiniMe Swap Writeup!!!

[baller status]

My guess is it's the bolts. I've always been told they are one-use-only and that they stretch once they've been torqued. ARP studs are much cheaper than OEM replacements, and the ARP are re-usable. But you have so many other problems with h/g so who knows. Could be the block. I just put an OBD2 D15B (3 stage VTEC) motor into my EG. Pretty similar to what you're doing. I like how you have the list of disproven myths so I'll try to throw in what I know. You can use a 85-87 CRX 12 valve EFI throttle cable bracket and it works a little bit better. But I would try a 96-00 Civic throttle cable if you can get one. Charcoal canister / purge control solenoid requires some vacuum line modification or you can convert to the 96 and later setup (my D15B doesn't have the vacuum line on the tb for the canister). I took the charcoal canister from an Integra because it's larger capacity and yet fits the Civic perfectly. OBD1 ECU's don't seem to be able to control the purge control valve from the OBD2 motors (that big vacuum valve in the center of your Y8 intake manifold). Just use the Y8 MT IACV. Use your OBD1 injectors (pretty sure they're all 240CC, even on the B series, but not 100% about the CX and VX injectors.) Use the OBD2 injector gaskets (O rings). You might have some trouble getting your fuel line onto the Y8 fuel rail. I had a lot of extra fuel lines, fuel bolts etc etc so I'm not sure exactly what I ended up using. You can't use an OBD1 fuel rail. 1.5 liter OBD1 non-VTEC dizzy ftw! As people have stated, don't use an aftermarket crank pulley because it doesn't have harmonic dampening, unless this is a pure race car where you can rebuild the motor after every race. The Z6 headgasket is the same part # as the Y8. A few years back they consolidated them. It's okay to use a slightly long timing belt because you have a tensioner. So if there is any doubt, DONT use the VX. Err on the long side. I put a 96 Civic timing belt on my JDM D15B. BTW it's a BELT, not a chain. If you've seen a timing chain you'd know that's something different.

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[Dasfinc]

Just FYI, The problem was the Head Gasket sucked, and it was under torqued, and has been fixed for me, for 24Tein we are unsure of what has caused his repeated failure.

honda EG headbolts ARE re-useable, they are not torque to yield (The don't stretch), they are hardend bolts, just FYI, but I wouldn't recommend re-using them more than once, and definatly not in a custom application such as my build-up where my CR is far higher than stock.

ARP studs are far stronger than OEM head bolts, and made life much easier when swapping out the bad headgasket, and they are MORE expensive then OEM head bolts which retail for $7 a piece, while ARP set was $135.

You can use a Y8MT IACV, but I didn't have one, so I cut off the metal that was in the way.

Yes, 1.5 OBD1 non VTEC Dizzy DEFINATLY FTW

Thanks for the info on the Z6/Y8 HG, I was curious if there was a difference.

[Dasfinc]

Originally Posted by baller status

Use your OBD1 injectors (pretty sure they're all 240CC, even on the B series, but not 100% about the CX and VX injectors.) Use the OBD2 injector gaskets (O rings).

You might have some trouble getting your fuel line onto the Y8 fuel rail. I had a lot of extra fuel lines, fuel bolts etc etc so I'm not sure exactly what I ended up using. You can't use an OBD1 fuel rail.

Yea, I'm nearly 100% certian the CX injectors are 240CC as well, but my OBD1 Injector gaskets fit just fine for me.

My fuel line had a little mounting clip on one side of it, but it didn't give me any trouble mounting to a Y8 Rail.

And yes, you cannot use a B7/B8 Rail on a Y8 Intake Manifold due to the diffrent bolt patterns, I'm sure you could drill it out if you really wanted to.

[Dasfinc]

Well, Everything has been ironed out except my low RPM Stutter that worsens after 10-20 min of driving.

Car idles fine and revs freely, Something in my ignition system is funky, or my timing needs to be advanced (More than likely since the head got milled)

and the Plug wires are 10.2mm Ebay affair, so I suspect those as well.

[24TEN]

Glad to hear yours is running and on the road

[Dasfinc]

Originally Posted by Dasfinc

Well, Everything has been ironed out except my low RPM Stutter that worsens after 10-20 min of driving.

Car idles fine and revs freely, Something in my ignition system is funky, or my timing needs to be advanced (More than likely since the head got milled)

and the Plug wires are 10.2mm Ebay affair, so I suspect those as well.

Sadly the wires weren't the problem, Injectors are clean, neither of my Y8 rails help, or my aftermarket FPR.

I suspect my Coil or IAT sensor is the culprit at this point.

Purchased a new coil, so I'll post up tonight hopefully with a running car!!!

[LumpyTheGrumpyCamshaft]

tune tune tune

[Dasfinc]

I have a basemap for my setup, tuning won't help me at this point

[Dasfinc]

Well, after checking over EVERYTHING I believe I have found out my problem...

Timing.

Looks like an Adj. Cam gear is REQUIRED for this setup, and noone can give me a straight answer

[Dasfinc]

BUMP! lots of new info!

[24TEN]

I've been waiting for an update

[Dasfinc]

Originally Posted by 24TEN

I've been waiting for an update

Looking forward to trying the D15B8 cam gear tonight to see what happens, it SHOULD take care of this problem, it all makes sense now

Why Vtec was pulling fine, while down low it was stuttering,
why no matter where I had the cam gear it wouldn't run right
why all the fuel/ignition systems work perfectly

Looking forward to letting it rip

[jdm-judah]

im new to this site so i cant go into the for sale fourms and participate and im very interested in your turbo set up some feedback would be nice like an e mail adress so we could talk about the set up thanks

[Dasfinc]

Originally Posted by jdm-judah

im new to this site so i cant go into the for sale fourms and participate and im very interested in your turbo set up some feedback would be nice like an e mail adress so we could talk about the set up thanks

PM'ed.

Here's a pictoral explaination of why you have to use a D15B7/B8 Cam Gear when using a Y8 Head that I yoinked from D-series.org

[Dasfinc]

And the IMPORTANT PART for a milled head, Ta-da!:



Going on tonight, gonna play with it till she spins like a top!

[Angry]

So can you NOT use the original d16y8 heads cam gear on say a d15b7 block?
Even if neither have been milled?

[95JDMEG9]

Mini-me's run HARD, especially if u have the set-up my homeboy has: d16y7 block d16z6 head intake headers exhaust, port & polished head and chipped p28 plus EX tranny and stock clutch, this set up is in a 94 eg coupe , beats ls swapped civics all day and ls tegs and i witnessed it beat a teg with a b20 and full bolt ons n clutch by 1 car length

[EF_9]

great work i love mini me's

[teal_dx]

good write up

a couple bits of info that will be helpful to someone doing this swap...


(stock harness)




wiring for the vtec oil pressure sensor goes to D6, the vtec solenoid goes to A4

and I got a T splitter for my extra coolant line when I had a Y8/D15b7 mini-me:



99-00 intakes have cold start assist holes that need to be filled. I used JB weld.





and those bottom tabs were hitting the IM bracket, prevent ing the IM to line up w/ the head:

[The Lobster]

did you ever get your timign right?

i have a y7/y8 and i have my dizzy all teh way forward to have it at stock timing.

as you i have shit for lower rpm power but great after 4 k.

i have an adjustable cam gear also. havent messed with it yet though.

[Dasfinc]

Originally Posted by The Lobster

did you ever get your timign right?

i have a y7/y8 and i have my dizzy all teh way forward to have it at stock timing.

as you i have shit for lower rpm power but great after 4 k.

i have an adjustable cam gear also. havent messed with it yet though.

I assume you mean you have a Y7 bottom end and Y8 top end? if this is the case and your head hasn't been milled I'd say you may be off a tooth. also, what brand of Camgear are you using? some of them say they work on all 88-00 which is incorrect, 96-00 have an off-set keyway, while 88-95 have a straight up and down keyway which even at TDC would cause you to be off half a tooth *4.5 degrees*

[Dasfinc]

Originally Posted by teal_dx

and those bottom tabs were hitting the IM bracket, prevent ing the IM to line up w/ the head:

I find it better to just REMOVE the intake manifold bracket from the block instead of cutting that part of the intake manifold off, however I had to cut the Tabs off the back of it for the IACV off my 92 to work.

[The Lobster]

Originally Posted by Dasfinc

I assume you mean you have a Y7 bottom end and Y8 top end? if this is the case and your head hasn't been milled I'd say you may be off a tooth. also, what brand of Camgear are you using? some of them say they work on all 88-00 which is incorrect, 96-00 have an off-set keyway, while 88-95 have a straight up and down keyway which even at TDC would cause you to be off half a tooth *4.5 degrees*

my bad my dizzy is actually almost all the way toward the rear.

trsut me my head has been milled and my block has been shaved.

sleeved and completely built y7 block, and completely built y8 head.

skunk 2 cam gear stage 3 comp cam

[Dasfinc]

Yea, if you aren't running an Adj. gear you are gonna be nowhere near right.

[l2ichard]

well i have a y8 head with a d15b.. and i have lag before 5500 rpm.. you think its the 1/2 tooth problem.. and you think a adjustable cam gear will fix this problem? thanks