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Old Feb 27, 2008 | 01:51 PM
  #46  
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Mark, the idea of mixing banks was nixed a few posts ago.
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Old Feb 27, 2008 | 02:09 PM
  #47  
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Originally Posted by 6.0-928S
That's the passenger side tensioner. On these cams the 'notches' are behind the sprocket. See what I mean about strange?

Hammer
The oil tube is still pointing in the wrong direction. The hole where the other end mounts is on the opposite side of where you have it going. I'm still confused about how yours is set up.

I've rotated your picture. The tube should follow the green path in your picture, not the red one. I assume you just haven't bolted the tube down yet, otherwise you've got a verrrry odd cylinder head.
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Old Feb 27, 2008 | 02:18 PM
  #48  
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Another thought...make sure you have the chain tensioners on the correct sides of the engine! Each side's tensioner is different, not just top/down opposites.
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Old Feb 27, 2008 | 02:21 PM
  #49  
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Big Dave, I have some 87 and 88 heads here and they all have the passage on the exhaust side like Hammer's. Could this be a difference between your 85-86 heads?
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Old Feb 27, 2008 | 02:24 PM
  #50  
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Originally Posted by Mike Simard
Big Dave, I have some 87 and 88 heads here and they all have the passage on the exhaust side like Hammer's. Could this be a difference between your 85-86 heads?
I suppose, but he has an 86.5, so it would be news to me that this was another mid-year difference!
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Old Feb 27, 2008 | 02:31 PM
  #51  
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Originally Posted by Big Dave
FYI...

My cam installation page... http://www.928oc.org/928oc_michigan/tbelt9.html
Very nice documentation, Dave.
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Old Feb 27, 2008 | 02:38 PM
  #52  
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I have S4 heads on the passenger side, mine points down to the exhaust side as well. mine are S4 heads, what are the ones you have posted?

mk
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Old Feb 27, 2008 | 02:47 PM
  #53  
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Originally Posted by mark kibort
I have S4 heads on the passenger side, mine points down to the exhaust side as well. mine are S4 heads, what are the ones you have posted?

mk
Apparently 85-86 heads are identical, but 86.5 models use S4 heads. I learned something new.
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Old Feb 27, 2008 | 02:48 PM
  #54  
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Sorry Dave, the engine is an 87. In my picture you can see the other end of the tube, I haven't installed the bolt in that end yet.

Hammer
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Old Feb 27, 2008 | 02:59 PM
  #55  
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Originally Posted by 6.0-928S
Sorry Dave, the engine is an 87. In my picture you can see the other end of the tube, I haven't installed the bolt in that end yet.

Hammer
Now I understand.
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Old Feb 27, 2008 | 03:44 PM
  #56  
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I dont think that is true. can someone verify that? i think all 4 valve 86s even the newer ones use the same heads. unless the newer ones use a similar casting to the S4 , but still the smaller valves.
anyone know for sure??

mk

Originally Posted by Big Dave
Apparently 85-86 heads are identical, but 86.5 models use S4 heads. I learned something new.
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Old Feb 27, 2008 | 04:01 PM
  #57  
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Originally Posted by 6.0-928S
Hi Adam,
It's not slack. Although I'm sure it would be more extended under oil pressure there is spring pressure as you can see from the bow in the chain.

Hammer
My bad Hammer, I thought the shiny tensioner post was just reflection from the camera flash.

Well, a little exhaust retard never hurt anyone, at least you won't have any issues with pump gas. Sorry, misplaced humor.

I just looked at the WSM. I don't see the tensioner installed in any of the pics Hammer. Maybe take it out and see where you are.
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Old Feb 27, 2008 | 04:06 PM
  #58  
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Originally Posted by mark kibort
I dont think that is true. can someone verify that? i think all 4 valve 86s even the newer ones use the same heads. unless the newer ones use a similar casting to the S4 , but still the smaller valves.
anyone know for sure??

mk
When my cylinder head for cyls 1-4 broke in '06, I bought a used '86 head. It was identical to the 85 head I was replacing. 86.5 heads may also be the same..as 85 and 86. Hammer revealed a few posts ago that he's using an S4 engine here.
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Old Feb 27, 2008 | 04:16 PM
  #59  
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One thing also to bear in mind is that the lobe tool is just to get you in the ball park right? Your crank is at 45 degrees right now, so the pistons are out of the way, and the tool is just used a fool-proof method method to make sure the cams are close. Actual timing at 20 degrees with the dial gauges comes later, and those adjustments could certainly put the cams out of phase so that they don't fit the tool I would imagine.

I'll be honest, I've never used the alignment tool. I think I'd have gone nuts if I came across your situation. If you're sure the LSA hasn't been changed by the regrind, I'd say move along.
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Old Feb 27, 2008 | 04:43 PM
  #60  
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I say remove the chain tensioner and check again. If it the gage fits, move on with your project. The tension on the chain is probably shortening it a bit, leading to your situation.
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