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Timing issue! Dohc Vtec Motor

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  • #455739
    jdm chinxxjdm chinxx
    Participant

      Ok so i need an expert opinion and i like to watch all ETCG how to videos and see the tricks and tips on whatever i need help working on, so decided to come here so maybe someone can help.

      I have a new crv b20 block with a Vtec Head which needs resurface cuz leaks oil between head and block, and vtec conversion of course. I put it all together, did the timing and now it runs smooth, but not sure timing is on right cuz i lack in power and that is my delema.. I know it has alot more power and parts are good, but will try and get compression numbers tomorrow, and i’ve tried 3 different ecu’s and they all run about the same.. but also think it could be from the leaking oil from head to block..its not bad leak but there is one.

      So this is where i’m confused, i used timing light and had it dead on the mark.. but felt very laggy in power, almost like i could feel the timing off. I maxed out the distributor and ran better more power on lower rpm and when engaging vtec, but still somewhat barely noticable lag so i experimented and cut the dizzy so i could retard the timing to the max, the more i push the dizzy toward the firewall, the more better it ran even tho the timing mark flew way toward the bumper about an inch or 2 when looking with timing gun.. It is weird to me but even this maxed and still feels a little laggy. Help?

      Throws the engine coolant temp code sometimes, and it did throw MAP but i rewired it CEL went away.. but when i plug it in the idle revs up to 2500 rpm, unplug it and it idles normal at about 1000..

      Does anyone have any ideas i really need advice, if im a tooth off and need to rotate both cams clockwise one tooth? or Counter clockwise? Or is timing on but could be something else like like distributor sensor going bad? Spark Plug Gap?

    Viewing 7 replies - 1 through 7 (of 7 total)
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    • #455740
      jacobnbr1jacobnbr1
      Participant

        I would tear down and re-check the mechanical timing belt to confirm it is in time cause to me it sounds like your off a tooth.
        You can actually have a good timing signal with a light but still be out a tooth somewhere.

        #455741
        EricTheCarGuy 1EricTheCarGuy
        Keymaster

          Just to make things simple how do you have the VTEC hooked up? If the VTEC is not hooked up correctly it won’t activate and therefore you will have reduced power.

          #455742
          jdm chinxxjdm chinxx
          Participant

            Thanks guys for getting back to me, I might have to tear it down and look again..

            Im pretty sure it has something to do with compression or timing..(compression numbers are great) I just ordered new basemap for a 2.0L Vtec map so should give me right fuel map and then i can see if that makes any difference in power through WHOLE gear and not only parts.

            VTEC works and engages just fine and has great power but right begginning of gear doesn’t pull as hard as it should, and before gear ends loses little power. Its not big loss but it is noticable i don’t want to over exagerate on it but you can notice.

            There are marks on the both cams and when i align to TDC the marks line up horizontally perfect.. Im assuming last mechanic that worked with the timing marked them to make it easier or if there is another reason to me thats unknown?

            Would i lose power through the head not being flat and leaking little oil?

            Would i be off timing by 1 cam or both? And say i push the distributor all the way towards the firewall and the timing light mark flys towards the bumper BUT makes more power, should i move the cam(s) 1 tooth clockwise? Since the more re tarded the timing is the better it runs?

            Advice most appreciated thanks ETCG & jacobnbr1! It makes it easier to trouble shoot knowing all the possibilities!

            #455743
            Third GearThird Gear
            Participant

              Well if the head isn’t flat, that isn’t going to help you in any way. So what head are you running on that, a B16 or what? You know you are at TDC if both the cam pullies say “UP” and the marks on the pullies are lining up to each other. The mark on the crankshaft sprocket should align with the mark on the block. What timing belt are you using?

              It’s possible to be off one tooth on just one cam. It sounds like the cams are in sync, do the marks on the crank line up when the cams are at TDC? You cams could be synced, but then you could be off on the crankshaft side.

              It could just be a tuning issue since you are putting together a hybrid engine.

              Don’t mess with the cam timing. If you retard your cam timing you will just be moving the engine’s power band higher and higher. Your low end will suffer. The opposite is true if you advance the cam timing. Plus I don’t know how much advance or retard is ground into those cams from the factory.

              #455744
              jdm chinxxjdm chinxx
              Participant

                I heard if you take to much off on the resufrace the head is no good, so they say if your looking for compression dont re surface the head unless you absolutly have to..

                Im using GSR head, GSR cams, B16 Toda timing belt, Unorthadox racing crank pulley

                You cams could be synced, but then you could be off on the crankshaft side.” —- This could be true…

                ^Thats what i was thinking, the cams probly are in sync as seeing it runs smooth and no problems or misfire and when i use timing gun i can get dead on the mark without having to use extra room i have from cutting dizzy up lol..But why does it have not good power when timing mark is dead on with timing light?

                Since i cut the dizzy and pushed it all the way toward the firewall, not sure if thats re tard or advanced, but seems to pull more and more power. i have to cut dizzy more for it to go further but again don’t want to slap valve or something pushing it trying to get timing on that way if its the CRANK pulley thats off.

                but crank timing probly off.. the pully is aftermarket so has TDC mark and 1 Timing mark i assume is 4 degree BTDC, my buddy said it could be off cuz its aftermarket.. but why would they make the part if it doesn’t fit right especially for timing? So i assume also its aligned to crank just as stock is.

                One more question is they say put cams up even with surface of HEAD.. that makes the cams sitting more like this not EXACTLY straight up | |
                I can take a pic to show my crank pully mark is at, and also where the cams sit at at same spot if that would help?

                #455745
                jacobnbr1jacobnbr1
                Participant

                  +1 the cams could line up but you still need to confirm the crank is lined at top dead center at the same time the cams are. Recheck the plug wires are in the correct distributor cap holes and not advanced one hole forward or backwards

                  #455746
                  EricTheCarGuy 1EricTheCarGuy
                  Keymaster

                    I’m with Jacob, it’s not just the cam’s that need to line up but also the crank and by the sound of it if you really have cranked the distributor to one side and the performance improved I would most certanially suspect an mechanical timing issue. Oil leaks don’t effect performance in my experience. Also go back and check your work to make sure everyting is connected correctly and you didn’t miss anything.

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