cam timing question

Technical Topics specific to the Hatchback body - NOT where you post pics/build specs of your car.
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cam timing question

By xtremejdm
- Fri Mar 14, 2014 9:25 pm #343395 So long story short I've been fighting this ignorant idle surge for a while now and also i cannot get my base ignition timing set as well. I can get it close by advancing the distributor all the way but it's obviously not correct so i got to checking the valve timing and moved a tooth on the cam gear which took it way too far. So heres the question I've been racking my brain on and going back and forth.

Moving a tooth on the cam gear and moving a tooth on the crank gear would result in different degrees of advance/retard as if the 2:1 ratio correct? Not that what I'm doing is the correct thing to do just a technical question i can't figure the logic out on.[/code]

By xtremejdm
- Sat Mar 15, 2014 5:41 pm #343413 Well if i get time today ill rip everything apart one more time and ill let everyone know if jumping a crank tooth has the same outcome or not.
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By suspendedHatch
- Mon Mar 17, 2014 4:35 pm #343464 If you don't jumper the ECU, the ECU will adjust the timing back as you advance it with the distributor. I came across MANY MANY Civics in this state when I used to do emissions.

Reset the ECU afterward.

By jefferydclark
- Mon Mar 17, 2014 5:38 pm #343466 first...what kind of engine do you have? bottom end the same as the top end? and you'll likely have the distributor advanced all most all the way usually anyway. note that if you have a d15 bottom end you'll need a d16y cam gear unless you are using a jdm d15b vtec camshaft.

By xtremejdm
- Mon Mar 17, 2014 8:11 pm #343468 I do always jump the plug when setting timing, and no honda ive ever had, or car in general has ever had to have the distributor fully advanced. 9/10 somewhere in the middle. And it is a b7 top & bottom end. The replys really dont go along with my actual question, but as i type this the most plausible answer now that i think of it is that ive done the head gasket and head has been surfaced and who knows who else has in its 270k miles. Probably past it's tolerance. Guess thats nothing a cam gear wouldnt fix. But no absolutely reason on a b7. :)

By jefferydclark
- Tue Mar 18, 2014 11:59 am #343485 well your idle surge is the FITV, IACV or TPS. if you clean the FITV and clean the IACV and that doesn't fix the problem, replace the IACV...if that doesn't fix it then it only leaves the TPS which has happened to a few cars I've dealt with. it cant be fixed by getting the timing right but even if you had the head surfaced the timing wouldn't be off so bad that you have to put the belt on all wacky. if you follow the timing marks on the bottom end and get the 2 timing marks on the head lined up with the surface, it should time perfectly. if it keeps running like crap with it timed correctly then your distributor may be going bad.

By xtremejdm
- Tue Mar 18, 2014 8:59 pm #343513 I apologize if it comes across that I'm trying to fix my car by jumping a tooth. It's just a general question. I know that it could be the iacv, which is new, or the fitv, which was bad but it now new, tps has been calibrated to 4.5v WOT and .48 idle with no dead spots or voltage spikes. As well as it could be any assortment of vacuum leak, misadjusted valves or bent valve, as well as the ECT or IAT sensors. Oh yeah or air in coolant.

By jefferydclark
- Wed Mar 19, 2014 4:59 pm #343544 well I guess I misunderstood the question. whatever your theory is...its wrong on the timing issue.

By xtremejdm
- Thu Mar 20, 2014 11:24 am #343576 Actually in theory i am right. You take material off of the botton of the head it creates more slack on the timing belt between the cam & crank pulleys. In return does result in a greater degree of retard. And no im not saying it results in 5° or 1° or .005° of CAM timing, which when using a timing light transfers to ignition timing. But as a mechanical standpoint that in fact is how it works. Yet AGAIN im NOT saying this is my timing problem, but it COULD add to it minimall. The car is 22 years old. How many owners did a head gasket like I did. Did they mill it to be true, did one decide they were doing themselves a favor and deck it, have I been the only one to replace the hg? Who knows. All im saying & that this post has turned into is anything modified other than stock has an affect whether it be positive OR negative. Not trying to down you or anything like that just stating the facts for which they are.
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By Virux
- Fri Apr 04, 2014 12:31 pm #344081 I don't really think a slight head shave and new headgasket are going to create enough to matter. It shouldn't affect your timing, since the belt doesn't rotate based on tightness, but by the teeth?

By xtremejdm
- Fri Apr 04, 2014 12:40 pm #344083 You may not THINK it has any affect, but in reality it DOES. 5x resurfaced could equal one hell of a deck, one resurface could result in one hell of a deck. Depends on how much needs to be removed to be true. The info is out there although i dont exactly remember its 0.0xx shaved = 1° cam timing retard
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By Virux
- Sat Apr 05, 2014 7:30 am #344125 Ah right, because the distance between tdc and the valves would be changing and all that. Silly mistake.. that sounds about right to me then.
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By m578elb
- Wed Apr 16, 2014 10:25 pm #344666 xtremejdm
Posted: Fri Apr 04, 2014 12:40 pm Post subject:
You may not THINK it has any affect, but in reality it DOES. 5x resurfaced could equal one hell of a deck, one resurface could result in one hell of a deck. Depends on how much needs to be removed to be true. The info is out there although i dont exactly remember its 0.0xx shaved = 1° cam timing retard

You can try an adjustable cam gear or new head, I'm just saying ,
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