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Forum namePerformance/Engine
Topic subjectMilled Head: Question about Timming.
Topic URLhttps://forums.2gnt.com/dcboard.php?az=show_topic&forum=i5&topic_id=81006
81006, Milled Head: Question about Timming.
Posted by Eclipse97, Sep-25-04 03:04 PM
I've got the head milled because it was warped. The guy at the machine shop said it was milled about "8 thou" I'm assuming its 8 thousandth of an inch.

How would I go about adjusting the timming while putting back the timming belt.

Thanks in advance.

2gnt rules.
81007, RE: Milled Head: Question about Timming.
Posted by Edisondaman, Sep-25-04 03:15 PM
.008 or 8 thousands of an inch is so small your timing won't change significanly but to answer your question, it retards the camshafts since the distance between the crank gear and the cam gear is shortened.
To compensate you would advance your camshaft about .25 of a degree ( less then 1 degree on your cam gears).
81009, RE: Milled Head: Question about Timming.
Posted by XtremeRS, Sep-25-04 03:43 PM
I had .008 taken off of my head, and it made for around a half tooth off on the cam gear timing marks, which equals approx 4-5 cam degrees. To effectively put the timing back to stock, you will need adjustable cam gears. Now I ran my setup half tooth off and it ran fine, but it was the intake cam that was mostly off, and the exhaust cam mark seemed to stay pretty close to stock. 8thousandths doesn't sound like much, but it will throw off the cam timing just a little..It just makes it a PITA to line up the timing marks when putting on the gears, since that half tooth just messes the whole procedure up..
81012, RE: Milled Head: Question about Timming.
Posted by DarkOne, Sep-25-04 09:41 PM
Originally posted by Edisondaman
To compensate you would advance your camshaft about .25 of a degree ( less then 1 degree on your cam gears).


Simplified: Your would adjust your cam gears to a degree much smaller than you can acurately gauge. Leave it alone, you won't have any problem.
81013, RE: Milled Head: Question about Timming.
Posted by Eclipse97, Sep-25-04 09:50 PM
Thanks for the help.

I'm on it! :thumbsup
81014, RE: Milled Head: Question about Timming.
Posted by Edisondaman, Sep-25-04 10:23 PM
Yep, what Dino said. Look at at this way, a single strand of human hair is approx .006 of an inch, it would really hard to compensate that small an amount, not impossible but not worth the hassle to set it up to read accurately.
81015, RE: Milled Head: Question about Timming.
Posted by DarkOne, Sep-25-04 11:10 PM
Originally posted by Edisondaman
Yep, what Dino said. Look at at this way, a single strand of human hair is approx .006 of an inch, it would really hard to compensate that small an amount, not impossible but not worth the hassle to set it up to read accurately.


Hey Eddy, would you mind explaining how you calculated this based on the amount of metal removed, for the benefit of the rest of us? I'm pretty curious myself, and it'd e a big help for people in the future.
81038, RE: Milled Head: Question about Timming.
Posted by Super20G, Sep-27-04 07:44 AM
Originally posted by XtremeRS
Since you had your head surfaced, depending on how much has been taken off in total, you could be 1/4-1/2 tooth off. When you set your timing, keep the crank at TDC ecactly, and if your cam marks dont line up perfect, get it so the marks are slightly above cam bolt centerline. When i had it set to below centerline, it had bad vac and ilded poorly, but set it for above centerline, and its great. Just try and keep the exhaust cam mark closest to centerline, and if you can, keep the intake mark slightly above centerline(intake slightly retarded).


Well I did XtremeRS's suggestion to the "T" when I just re-assembled the motor, waiting on a few fuel fittings before I start it up and see if the timing is correct. *crosses fingers*