EOIC VALVE ADJUST ?

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mbaird

mbaird
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I flew out to MN to help my brother install a freshly ported top end on his 69 400 Firebird and we adjusted the valves using the EOIC method .
On the last cylinder I realized I was turning the crank in reverse rotation! LOL. So I readjusted cylinder 1 going clockwise and found no difference.

Question is does it make a difference?
Funny thing is that I realized it when he mention I was just tightening the dampner bolt at on point and I thought that is not possible because all the plugs are out … OH **** ! Lol

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You should double check that the dampener bolt is still tight if you have been rotating the crank backwards using the crank bolt. The Pontiac dampener just slides on by hand & is held in place by 160 ft/lbs on the bolt. If that bolt was not fully tightened, it may have backed off some from turning it CCW.
 
You should double check that the dampener bolt is still tight if you have been rotating the crank backwards using the crank bolt. The Pontiac dampener just slides on by hand & is held in place by 160 ft/lbs on the bolt. If that bolt was not fully tightened, it may have backed off some from turning it CCW.
Oh yeah … it is definitely getting retorqued
 
We got the engine buttoned up and installed a new 12 bolt posi with 3.73s . Car runs like a scalded cat ! It should run 12s easy . Not bad for a stock appearing 3sp car !
 
I THINK it could be off? You see the exhaust valve start to open and (going the wrong way) it really is on the closing ramp. I would double check it.
 
U say u were tightening the damper bolt then u were not doing reverse rotation.
No … I only had enough room to rotate the crank with the breaker bar on the passenger side and wasn’t thinking about it being reverse rotation until my brother said he thinks I am just tightening the bolt . I thought well that’s not possible… and I realized I was going in reverse rotation. Brain fart …. So we checked them , started engine and took it for a drive then redid the adjustments in the correct rotation while it was hot and lifters pumped up .
It does make a difference. Some were 1 turn loose.
Car runs great ! I would still like to recurve his distributor though and set initial to 16-18 with 34 total . Right now its at 12 initial and 35 total .
 
If one truly does the EOIC method while turning the engine in the opposite direction, you’re adjusting the lash/preload during the overlap period.
You’re at the opposite end of the lift cycle for each valve from where you want to be
 
If one truly does the EOIC method while turning the engine in the opposite direction, you’re adjusting the lash/preload during the overlap period.
You’re at the opposite end of the lift cycle for each valve from where you want to be
Yep but close enough to start it , get it warmed up then reset correctly
 

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