What head for most torque/low end power?

SiRwagonSiRwagon Band Wagon
in Engine & Drivetrain
ive read that the y8 head has more low end power band do to its port swirl design(?) but just about everyone i read about does the z6 head(either whole block or mini-me) my goal in building up my engine is for a fun dd that had better low end power band for torque for in city driving and freeway passing. what is the best head to use for a mini-me? thanks guys

Comments

  • superhatchsuperhatch Moderator
    I think the reason most people do the Z6 is that it is obd1, vs the Y8 which is obd2. That's the only thing I can think of (assuming youre going to use the IM from the head).

    Honestly it probably isn't going to make -that- much of a difference on a fun DD that isn't built as an all out machine. I doubt that you'll feel the difference between 3-5 ft/lbs.
  • 1988rt1988rt Senior Wagonist
    Have you guys ever tried a D16Z6 with a 99-00 D16Y8 cam and 96-98 D16Y8 intake manifold? We just did one in a crx and it rips
  • SiRwagonSiRwagon Band Wagon
    whats the differance between obd-1 and obd-2?
  • 1988rt1988rt Senior Wagonist
    The y8 cam is larger than the z6
  • SiRwagonSiRwagon Band Wagon
    is the y8 cam size require a different obd?
  • The_HeadThe_Head familEE
    My old wagon has a Y8 head on it. The A6 distributor is comptable with a Y8 head. The owner before me had installed a rpm activated switch for VTEC instead of doing an OBD conversion. He also had the cam gear retarded a couple degrees claiming it helped the low end power. I never changed that when I owned the car.
    farfrumwork wrote:
    Yes, still the D16A6 ECU (PM6). I’m not sure if it runs lean in vtec (no means of truly evaluating this, like a wideband) but many people have run such setups – search the Honda-tech forums for others experience if you want. You could always run the vtec ECU (but you need a special harness and dizzy – iirc... it’s been a while), or have the PM6 flashed to run a vtec fuel/ign map.

    It is like ~10:3-1 compression so I run mid-grade fuel here at altitude. I’ve never had any known knock or detonation, and it pulls really nice down low (high compression and good flowing heads) in addition to more power up-top. The low-mid end (2,000-4,500) is where it’s used most though. MUCH improved over the stock A6 head.
  • SiRwagonSiRwagon Band Wagon
    So i could run vtec without doing the pmfi obd? Are u sure
  • The_HeadThe_Head familEE
    I don't know about having a PM6 ECU converted to run VTEC, but he ran the rpm switch for like 2 years and said it was fine. If it were me I would have done a OBD conversion though in order to use a P28 ECU.
  • byrne_06byrne_06 New Wagonist
    I was thinking about putting my supercharger off my rex on to my wagon i just picked up, i made a 197whp with it and 175ft/lbs, bunch of low end power and suprising reliable. Just a thought

    edit
    Ya i read the title wrong my bad lol
  • VIPwryannVIPwryann Wagonist
    Well to make bottom end TQ, KEY word: "compression" Most likely Y8 for the win









    Well in my option, The Z6 head is the way to go! But I'm bi-est because I have only ran Z6 heads!! and I'm have build and tuned my D16z6 engine to over 650whp!! Maybe someday I will try a y8 head?? But its been easy to get a hold of Z6 heads!!

    Well two sides here..." its really up to you" that's the right answer LOL


    Z6- older head, easier to get You have the open combustion chamber, some people like them due to more clearance for High comp pistons.



    Y8-newer head, but shitty crank in ( y8 bottom, so still easy head to get, LOL, will "raise compression over Z6 head" closed combustion chamber, alot like most factory turbo cars come with, DSM's ect.comes with Bigger intake plenum too.



    Please add... to my list???
  • 1988rt1988rt Senior Wagonist
    I ran a z6 in a 1988 civic si and all i did to run v-tec was hook up a tack and run the solenoid to the shift light so then i could change the v-tec :lol:

    I was getto
  • SiRwagonSiRwagon Band Wagon
    so the higher compression of the y8 head is what will give me more torque?
    looks like i need to start looking for one. thanks guys!
  • hidenplanvewhidenplanvew Band Wagon
    Y8 crank isnt the problem compleatly, The y8 oil pump flows less Gpm compare to the Z6 but can be corrected by porting and shimming the oil pump. The crank is not the best it has one oil port at each rod, unlike the z6 crank that has 2 for the rods and the y8 runs tighter clearences unlike z6 so it likes thinner weight oil for carb and emissions and all that dumb stuff. So they Y8 head Vs the Z6 head this has been a battle for a while. The Y8 dont flow as much air as the Z6 and the Design of the intake ports on the head has somekind of weird design. The best combo you could really do is a Z6 head with Y8 intake manifold and a Delta 272 cam just cause you dont need springs and retainers unless you take it above 8k alot. Z6 head can run supertech springs w/o having to get the retainers so it keeps it cheap and you can go to like 9K if you want. The Y8 combustion chamber has a diffrent design then the Z6 that makes it have a bump in compression. There are a few highs and lows of the Z6 over the Y8 but Low end is really hard with D series motors they are made to perform in the mid to high Rpms
  • hidenplanvewhidenplanvew Band Wagon
    Oh and I would honestly just do a OBD1 conversion and run a P28 ecu. Also timming with a Z6 head one a A6 block is easier then trying to do the timming with a y8 on A6. The best thing you could do is swap a Z6 compleat motor over switch to obd1 and run your vtec in the wire harness. Sell your motor to guys who are usinging them for drag racing cause there "stronger" then the Z6.
  • 88jdmcivic88jdmcivic Band Wagon
    my personal option, if you want low end power then go with the DOHC ZC, that has alot of low end power and mid and high range then go with the Z6 or y8 (long block) and want more power then the SOHC ZC vtec.
  • kylerwhokylerwho Wagonist
    if you want low end power then grab the d17a1 crank, rods, and pistons and throw them in the d16a6 block with a y7 head and use a z6 head gasket.

    you will bump up the displacement to 1668cc with a compression of about 9.6:1

    that way you wont have to worry about converting to vtec conversion and you will have a better port flow. plus the y7 head uses aluminum rocker assembly so that will be lighter and help open up a minute amount of power.
  • hidenplanvewhidenplanvew Band Wagon
    I wouldnt waste money on a zc sohc or have to deal with finding parts for a dohc (just personal opinon).. Get a Z6 and use some stock pistons and bump up compression and use a delta 272 cam with a milled head.. you could always get a small t25 turbo for low end but it will choke the motor abouve like 6500 or use a t28 all of which could be had for a very good price.. Also ebay intercoolers work great for budget builds!
  • The_HeadThe_Head familEE
    Basically you need either compression and/or displacement and/or forced induction. A head swap might help, but not much really.
  • kylerwhokylerwho Wagonist
    ^^^^that is the truth.


    just throw some p29 pistons into your a6 would be the easies of all solutions. your compression would be 10.79:1.
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