Hey all! After months of research and collecting parts, I started to do a D16Y8 MiniMe headswap onto my D15B8 Block. Lets Start with some Background on the car: The Victim: The car started life back in 1992 as a bottom of the line Civic CX 5 speed Hatchback *With AC * when my parents bought it brand new off the lot. A Divorce, a sister, and an IRS Tax Evasion later my dad gave me the car back in late 2006. The car having sat in the city for 3 months had a dead battery *Which I replaced to get home* and it then popped its headgasket the following week*.... Car sat untill March of 2007 when I finally replaced the headgasket and had it as a spare car for a few months, now keep in mind I drive a 2007 Ford Focus SE as my daily driver and this honda was to be my project, and considering my ford was FAR faster than the Honda I had read that putting a DX/LX 16 valve head with a D16A6 Camshaft and Y7 Cam gear would give me a little bit of help, and I had noticed that my D15B8 block had 4 valve pistons (I do not know how long the CX's head 4 valve pistons, so please don't come yelling at me if you have a 92 that doesn't have 4 valve pistons) when the head was off. so in late may we Converted the car to a P06 ECU and moutned a D15B7 Head with the cam and gear and found the car to be a bit more lively, along with an intake, header, test-pipe and exhaust. but after running an 18.5 at the track. *The CRX in front of me is my buddies stock 89 SI and he ran a 16.5 I was less than thrilled, and found out I was leaking compresson hard-core and found out that the valves, or valve seals were toast, so I decided "What kind of power can I get out of this little D15B8 Block." *And yes yes, a D16Z6 transmission has been paid for, I'm picking it up as soon as possible* I aquired a D16Y8 head with a OBX intake manifold for free, and decided this would be the direction I'd be taking. I dropped the head off at my local machine shop and had them rebuild the head so I knew I'd have something clean to start with *HIGHLY RECOMMENDED* because when you buy a used head there is no real way to find out if the valve seals are toast, or if the valves are bent unless the head is ON the block. (the head I got for free I was told was perfect, Turns out 2 of the valves were bent) So lets start with the common mis-conceptions of this swap, along with a shopping list so incase you are interested in doing this swap yourself you have a quick FAQ. 1) You can just use a set of D15B7/8 or D16Y7/8 headbolts - WRONG, Because of the design of the Y8 head, the corner closest to the Vtec Solenoid isn't raised on the Y8 head, so that corner requires a Y7/Y8 Headbolt/stud. 2) I need a Y8 Distributor, and have to convert it, OR I need a Z6 Vtec Distributor - WRONG, You can REUSE your origional CX/DX/LX Civic Distributor, the Z6 Dizzys do NOT bolt up at all, and the Y8 Dizzy will require custom wiring, or a adapter to work with your OBD1 Harness. 3) Any SOHC Vtec solenoid will work on any other SOHC Vtec Head - WRONG WRONG WRONG You HAVE to have a D16Y8 Vtec Solinoid Its gasket is like 3 stacked ovals, the Z6 Gasket has a triangular shape, they look VERY SIMILAR without them being off the head, and I think the D15B Vtec Solenoid may be yet ANOTHER shape. 4) You have to wire Vtec/4 wire O2 all the way to the ECU on any Civic - WRONG My 1992 has the wiring for Vtec, and the 4 wire O2 up to the Shock-Tower, but to my understanding this is ONLY for 1992 Civic EG's, I'm not sure about the Coupes or sedans. 5) I can reuse my FPR off the D15B7/8 Fuel rail - WRONG the Fuel rail on a Y7/8 Manifold flows MUCH better, and the FPR is mounted on the opposite side of the rail *And is off-set* so it will not work 6) I can reuse my Throttlebody off the D15B7/8 - CORRECT This has the same bolt pattern, and I have been told that certian B series TB's will also work as well. 7) I can use a P28 ECU for this setup - EHhhhhhhhhhhhhhhhhhhhhhh I personally had my Y8 Head milled, and am using ARP studs with a thin D16Y8 Headgasket, this setup mounted on a D15B7/8 Block creates MUCH higher compression than a stock Y8 *9.6:1 CR while my setup will be running 10.8-11.1:1 CR. I STRONGLY recommend getting your ECU chipped, no matter what ECU you have your hands on. 8) I have to use a Chipped P28 ECU for this setup - WRONG P05 and P06 ECU's can be converted to Vtec spec, and be chipped to operate the same as a P28 would, I sent my P05 ECU to Phearable.net and received it back 4 days later chipped and converted for Vtec ready to rock and roll. 9) The D16Z6 head and the D16Y8 head are basically the same - WRONG the Z6 head has 'straight through' intake ports, while the Y8 had Tumble ports (Z6 has better top end, Y8 had more low end grunt), as well as the combustion chamber is smaller on the Y8 head which will help bump the CR a few more tenths, you can tell the difference between the Z6 and Y8 by looking at where the valves are and if the chamber is completely squared off and flush with the head, its a Y8, if its recessed a little bit, its a Z6 head. 10) I need a Z6 Oxygen sensor - Ehhh.... If you have a CX like me with a 1 wire O2, you will need to lay fresh wiring from the shock tower (or ECU if you don't have a 92) for the 4 wire O2, if you have a DX/LX your O2 will work just fine, if you have a VX, You're gonna have to convert that to a 4 wire. 11) If I followed all the above rules I can just slap that bitch on their and away I go! - OH GOD NO, I learned my lesson the hard way, When using a D16Y8 head, Cam, and Cam gear, your head will be off 4.75* (Half a tooth) compared to the TDC of the pistons on your B8/B7/Z6 block. You need to use either an adjustable cam gear, or Run your origonal B8/B7/Z6 cam gear on the Y8 Camshaft to remedy this problem, otherwise your timing will never be correct. You also need to be sure to adjust your valves (While they are cold, atleast 1 day of sitting) before you fire that sucker up! Alright Enough of that, now onto the shopping list for the swap!!! You'll need: 1) D16Y8 Head - Strongly recommend a freshly rebuilt head 2) 92-00 Intake Manifold - I got an OBX one for free, looks like it will work fine, but MANY people use the 96-00 EX Intake manifold with great success, I'd strongly recommend it as well because its OEM and its superior design *edit* OBX one was AUTOMATIC only, Cannot use it. I've picked up and am using a D16Y8 OEM MANUAL Intake Manifold. 3) 1 D16Y7/Y8 Headbolt or Stud, 9 D15B7/B8 Headbolt or Stud, Do not mix and match these, I got a custom set from ARP for only $135 shipped to my door, don't buy these on Ebay. If you are on a tight budget, Buy 1 brand new Y7/Y8 Headbolt and re-use 9 of your D15B7/B8 bolts (YES they can be re-used because they are hardened bolts, not torque to yield, but I wouldn't re-use them more than once. Be aware, you need to torque this to I believe 55-60ft-lb, not the 47 origionally meant for the B7/B8 Block 4) D16Y8 Head gasket, 3 layer metal OEM gasket is ideal, I wouldn't use any other kind of gasket as thinner and you risk bumping your CR to nearly dangerous levels, thicker (Most likely not a metal gasket) and you risk the reliability of your setup *edit* I used a Egay Headgasket, it failed Immediatly, Turns out you can get an OEM D16Y8 Headgasket from HONDA for only $31, call your local Dealership and pick up this part. 5) A spare wiring harness, a 92-95 EX/SI Harness (If you have a 92 you can simply replace your entire engine wiring harness with this and it will all just be plug and play), or just a clipped Vtec plug and 4 wire O2 Plug (my CX has a 1 wire O2, if you have a DX/LX you don't need that), I bought a 92-95 EX/SI Harness, but at the last second decided to keep my stock harness since I KNOW it works, and just lay fresh wiring for the O2 and Vtec solenoid. 6) This stuff: Jack, Jack stands, good selection of tools (I have ALOT more tools than I took a picture of, but the basic kit gets the point across) Coolant, Oil, Oil filter, Injector cleaner (Since its all gonna be apart, now is a GREAT chance to clean the piss out of your injectors by gently dipping the tip in some injector cleaner and gently wiping it off) Rags, Simple Green (Nice for cleaning crap off of stuff),. 7) This Stuff: Y8 Spark plugs, (I recommend NGK's) Spark plugs Wires *OEM, or generic is really fine unless you plan on running an aggressive ignition system, I got Z6 iridium plugs and 10.2mm wires (Turned out the plugs are the same for either head) because I have an accel HEI Super coil and will be screwing with my timing quite a bit, a new Alternator belt (Mine was pretty much shot, and I am running a UDP Crank pulley), O2 sensor (Again, if you have a DX/LX you don't need this), D16Z6 Timing Chain THIS IS THE RIGHT BELT, If you are doing a Y8 swap on your B7/B8 bottom end, USE the Z6 belt, it fits perfect, and tensions perfectly), Water Pump (Because its only $35 and if it fails you're fucked, you might as well replace it) Some Vacuum tubing is nice to have in case you have to change anything around, some T's would be a good idea also. 8) Cute assistant: Check. THE PROCEDURE!!! I have ALWAYS used my trusty Haynes manual when I am removing the head from my car, and if you don't own one, I'd buy one before even popping your hood (For 88-95 honda civics, you only really need ONE bit of information out of the 96-00 manual but I will post that information later on, but the basic procedure is as follows: 1) Drain the oil out of the car - You are gonna have to do ANOTHER oil change shortly after the swap as well to ensure you have all the coolant you are about to spill into your oil out of your engine 2) Drain the coolant - (Small Wingnut on the far pass side of the bottom of the radiator) 3) Bust out the Masking tap and Permanent marker, This makes life SO much better for re-assembly, unplug connectors one by one from the head and intake manifold, being sure to label every single one as you remove it (MAP sensor, TPS sensor, etc etc) If you swap your MAP and TPS by accident when re-assembling and have a chipped ECU you can Fry it very quickly and easily. 4) After the oil and coolant have drained, carefully remove the coolant lines from the intake manifold and head, do this carefully, and be sure to CHECK where the Coolant lines go, because some of them loop back, and around etc. 5) Label and remove all vacuum lines from the intake manifold and Head, again makes life that much easier) 6) get under the car and remove the bolts that hold the intake manifold Bracket to the engine, just by (I think above) the oil filter, now would be a good time to put the new oil filter on as well (Trust me, you don't need it anyways, and its a PITA to try to remove the bracket from the Intake Mani) 7) remove the Dizzy from the head, and put it aside (B7/B8 Dizzys work on Y8 Heads, I don't care what anyone else says, worked PERFECTLY) 8) remove timing chain covers *Both upper and lower* and loosen the timing belt tensioner slightly, and remove the timing belt from the head. (You will need to replace your upper cover with one from a Y7/Y8 if you plan on covering your cam gear) 9) Remove the valve cover from the head, and refer to haynes for proper procedure to remove the head from the block, again ensure EVERYTHING has been disconnected from the intake manifold and head, be slow and careful when doing this. I typically leave the intake manifold on the head when removing it as the bolt on the bottom center of the intake manifold is a HUGE pain in the ass. (Don't loose the Dowl pins that go between the head and block to help line the head up, you will most likely need these on your new head) 10) Pull out the the Oil Jet that will be in your block just above the top middle Headbolt hold between pistons 2+3 You can see it in that picture as that little pin-hole above the headbolt hole, grab a small screw, and gently hand thread the screw into the oil jet and remove it, it will come right-out. 11) Take a look at your crappy old head You can see how bad mine looks, the valves were chipping, and I think I had a small crack on my #1 combustion chamber between the 2 intake valves. 12) Sit back, and have a drink. I hope this has been informative to everyone, and I hope an Admin can move/stickey this in the write up section as it was VERY hard to find out how to do this swap with a complete write up with do's and don'ts And until next time, here is a picture of a co-worker of mine! CHAPTER 2: RE-ASSEMBLY!!! Alright, now that you are ready to bump you stock CX's 70hp up a notch, it is time to re-assemble it all. Again, I recommend removing the intake manifold bracket attached to the block, as well as attaching the intake manifold/TB to the head prior to mounting the head for ease of reaching the lower intake manifold bolts. When Switching to a D16Y8 intake Manifold *mine was completely bare* I switched over my Throttle body *MAP and TPS sensors*, EACV (IACV) *The thing toward the firewall that has 2 coolant lines going to it*, IAT, and Purge Control Solenoid* you will discover a few things. A) The IAT no longer has a home *The little white prong thingy that was screwed into the back of your old intake manifold* You can just drill a hole in your intake plumbing and screw/RTV it into place and you may have to make the wires a bit longer for it to reach, but I currently have mine just mounted off of one of the large Vac lines off the top of the Y8 Intake Manifold and it hasn't given me any problems yet. B) The Purge Control Solenoid *2 small Vac lines, 1 to the manifold, 1 to the canister* no longer has a mounting point, Mine is just hanging, but it seems fine IMO, I may mount it to my firewall later with some longer Vac lines. C) The EACV (IACV) Won't Fit because of the casting on the Y8 Manifold. We took an angle-grinder to the back of the intake manifold and carefully hacked off the casting tabs that were in the way of my B7 EACV Valve. Back to the head: Remove the Plastic guard behind the cam gear *You will have to remove the cam gear for this* and replace it with the one from your CX/DX/LX head so your timing chain cover will mount correctly. I used ARP studs for my setup, put the 1 Y8/Y7 stud in the corner closest to the passenger seat *Vtec Solenoid corner* and the other 9 in the remaining spots, Make them tight/snug with an hex key socket and then lay down the gasket (I used copper spray on both sides of my HG for a bit of extra insurance). At this point go ahead and remount the head/intakemani/TB and torque the nuts per the Haynes/chiltons manual. Be aware ARP Studs for this setup require a 12 point socket, not the typical 6 point you'd normally use. ALSO do not mount the head with the sparkplugs still in it so you get the most accurate torque possible when doing the head bolts/studs Begin re-attaching all your pre-labeled lines to the head *Everything on the head is in the same position as the old head, same with the TB, the differences are gonna be on the Intake manifold and Fuel rail, be sure you remember where everything goes SPECIFICALLY on the Intake manifold as some things have changed distance and will require new plumbing. Also, the fuel pressure regulator is going to need a much longer piece of tubing than origionally on it, so you will need to pick up some small emission line tubing to connect the FPR to the intake mani. also the fuel return line had to be lengthened as well * I used a plastic Straight-through connector with some more tubing for it to reach* Once everything has been re-connected, if you have a DX/LX all thats left is wiring Vtec *Many different articles on how to do this, I'll add a link later, and probably a picture* For us CX owners we have to wire the 4-wire O2 as well *Will work on a small write up for that later* that leaves us with just a few small things left, Bringing the motor and head to TDC, Attaching our Timing Chain (MAKE SUPER SUPER SUPER SURE you are at TDC on your head and block after you've tightened the tensioner back down, and be slow and careful when you are bringing them both there. After you are on TDC You can re-attach your timing chain cover and crank pully, Attaching our Crank pully (I sure hope you didn't loose that Woodruff key when you took that bad-boy off) should be fairly easy at this point, be sure to torque it correctly as I've read a few horror stories about crank pulleys falling OFF of running cars, so be sure you triple check it. After that is done, slowly spin the crank with a 17 mil socket on the crank bolt to double check for clearances *Leave your sparkplugs out for this so you have no pressure and can feel if you are hitting a valve or not* I'm using a lightweight Aluminum crank pulley with NO accessories except for the Alternator, keep in mind that you WILL need to purchase a smaller belt if you are doing this I purchased the 'stock' belt and it was 3 inches too big. *The belt in my picture EARLIER is the correct part number if you are re-using the stock crank pulley* I'll return later on this week with the final chapter in this project! Current Chapter: Well... Blew the headgasket AGAIN... But here are some teasers of my Epic Failure. Kaboom. I'll have it running right soon enough. FINAL CHAPTER! After replacing the headgasket again I still had a bad miss/stutter down low and after a TON of research found that you have to use a D15B7/B8/ D16Z6 Cam gear ON the Y8 head otherwise the TDC of the cam will be 4.75* (A half tooth) off from your crank and it will run like piss, I'm changing it out tonight and will give my final verdict!