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i searched for awhile and came up with valve adjustment specs, valve cover questions blah blah blah blah blah.
anyways i would like to know the minimum valve to valve clearance. i thought i read .030 which is the same as piston to valve clearance.

Combustion Contraption

No. .030 is too much, if i remember correctly, depending on app (race/street) its between .010-.020.

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ok. i was just mocking up my spare head just to see my valve to valve clearances with different cam gear settings writing them down as i went. even at my cam gears at 0,0 i was about .030 from hitting each other. i just wanted an idea of the maximum adjustment i could take my cam gears to.
if anyone knows for sure please chime in. thanks for your input CC.

97CTR

endyn looks like they run theres at .040" http://www.theoldone.com/artic...s.htm

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i got a PM from a head porter that says .020. looks like we got lots of different opinions.
i bet CC knows who PMed me.

thanks for the info and link. im getting close.

DonF

The closest I have run is .019, and that was at 5 BTDC. And on a big (1200) over-rev he bent the valves. At that number you better have really god valve guides and set each valve spring. .030 is really safe and you do not have to check belt tennsion every week.

RMF

Here is something to look at
http://speedtalk.com/forum/viewtopic.php?t=1098

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well i ended up putting the valve to valve specs that ive captured so far on a microsoft word table just so i can prepare myself for the "race head" that should show up soon. just wanted to see what kind of time its going to take to get this thing figured out.
at .020 clearance i can run my cam gears +1 and below to have proper valve to valve clearances.
but if i increase it to .030 i can only run my cam gears 0 and below.
i derive these #s from IN-EX=? then i can have a general idea of what maximum settings i can use on my mock up head.
hopefully this makes sense. i tried to change the format of the table i made but its not working apparently. when you read the clearance from left to right going diagonally it seems the clearance is almost the same throughout. i have exhaust cam settings at the top and intake on the left side of the table.

DonF

How much are you factoring in for valve growth ( heat expansion) and belt growth?

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im not a professional like you donF. how in the hell do i figure that out? so basically i havent figured in valve growth. i run my belt pretty tight so even that part of the timing mechanism should be ****.

DonF

In true engineering speek, unless you are Cosworth, Illmore, Mercedes, HDD, you run them closer and closer until it goes BOOM. Then back off a bit. I would shoot for .030 just incase you miss by a little.

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well im already recouping from a mishap at the beginning of the year and i think my wife would definitely divorce me if i killed another motor. i dont have the budget of cosworth or mercedes so i guess ill stick to .030.
as it was when i tore down my motor from 04-05 i had small dents in my valves from clicking one another so i was already cutting it close.

DonF

See, you were getting the "engineering" right, if you had numbers from that engine you would know the answer. That would be, a little more than the last one. That is how I found it. LOL