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Old Feb 27, 2008 | 02:20 AM
  #31  
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Originally Posted by mark kibort
I traced them and was going to make a set out of wood. Hasnt happened yet, but i do have the tracings.
I'd love to get those too.
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Old Feb 27, 2008 | 08:31 AM
  #32  
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Hammer, you could have the 1-4 bank and 5-8 bank cams mixed up. The sprocket is offset differently on each bank, if that's the case it would be both cams that are incorrect. BTW, I'm very intimate with cams because I'm making some right now, it's mind boggling to keep up with the details of each but IIRC the sprockets are offset forward on 1-4 and rearward on 5-8.
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Old Feb 27, 2008 | 10:55 AM
  #33  
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I will get up to my shop & post my investigative results as soon as I can. I thank everyone for the thought food. With everyone's help I will get to the bottom of it.
One thing, I used someone's illustrated directions on my install. I noticed that in Big Dave's pic the patterns he used & I used were reversed. That may be my problem. I'll check it out.
Thanks again, Hammer
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Old Feb 27, 2008 | 11:38 AM
  #34  
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Hammer....I keep staring at your first picture with the chain tensioner. Are you sure it's installed correctly? The oil feed line looks odd, like it's pointing the wrong direction.
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Old Feb 27, 2008 | 11:52 AM
  #35  
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Originally Posted by Big Dave
Hammer....I keep staring at your first picture with the chain tensioner. Are you sure it's installed correctly? The oil feed line looks odd, like it's pointing the wrong direction.
That's the passenger side tensioner. On these cams the 'notches' are behind the sprocket. See what I mean about strange?

Hammer
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Old Feb 27, 2008 | 12:11 PM
  #36  
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Does the tool assume that the tensioner is engaged? Your's is totally slack. When I do cam timing, I use Louie's tip of wedging the tensioner open to the same extent it would be if hydraulicly pressurized.


Originally Posted by 6.0-928S
I installed my new timing chains & installed my modified cams. Using the Porsche tool this is what I got.........
With the cams 7 links apart the lobe profile doesn't fit in the tool even if I rotate the cams. Any one seen this before?

Hammer
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Old Feb 27, 2008 | 12:23 PM
  #37  
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Originally Posted by atb
Does the tool assume that the tensioner is engaged? Your's is totally slack. When I do cam timing, I use Louie's tip of wedging the tensioner open to the same extent it would be if hydraulicly pressurized.
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
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Old Feb 27, 2008 | 01:04 PM
  #38  
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Is the first pic taken from the back of the engine and the second pic from the front? That would explain why it looked funny to me.
How are the cams "modified"?
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Old Feb 27, 2008 | 01:18 PM
  #39  
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I thought he was grinding the base circle for more lift.
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Old Feb 27, 2008 | 01:21 PM
  #40  
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Originally Posted by Mike Simard
Is the first pic taken from the back of the engine and the second pic from the front? That would explain why it looked funny to me.
How are the cams "modified"?
Very good Mike. You're the first one to notice, 1st pic is from the rear, 2nd from the front.
They were plasma welded & reground.

Hammer
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Old Feb 27, 2008 | 01:30 PM
  #41  
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Did you rotate the cams slighly so that the alignment checking tool makes better contact?
Did you measure the space between the indicator marks??
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Old Feb 27, 2008 | 01:32 PM
  #42  
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Ah, that explains that.
Some random thoughts, if one cam were off a tooth the 113mm would be off by about 4mm at the cast pointers. That doesn't look to be the case.

If the new valve timing was different it could have the tool sitting like that. 10 degrees of valve timing would move the opposite end of the alignment tool 3/8"
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Old Feb 27, 2008 | 01:43 PM
  #43  
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Originally Posted by Mike Simard
Ah, that explains that.
Some random thoughts, if one cam were off a tooth the 113mm would be off by about 4mm at the cast pointers. That doesn't look to be the case.

If the new valve timing was different it could have the tool sitting like that. 10 degrees of valve timing would move the opposite end of the alignment tool 3/8"
The lift & duration are increased but the LSA can't be moved.

Hammer
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Old Feb 27, 2008 | 01:47 PM
  #44  
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how can that be possible???? the exhaust cam for bank 5-8 is totally different . it has the long bearing surface near the pulley.

also, look at the vertical indicators, if the intake cam was change to the 5-8 side, it wouldnt be pointing in the right direction for the tool.

the easy way to check this is just look at the end of the cams for the serial numbers and verify with the manual.

im still thinking its off one tooth, and you can measure the distance to verify that, or he needs to rotate both cams a little until the exhaust side of the alignment tool touches the exhaust cam. notice the tool is on the intake cam lobe but not quite to the exhaust cam lobe? one tooth might be the answer.

This is also why it is important to set the cams in the chains on the ground by using the tool. Then, as long as you dont skip a tooth, you place the cams in the bearings and lock them down. the rest is just double checking, and no surprises.

mk

Originally Posted by Mike Simard
Hammer, you could have the 1-4 bank and 5-8 bank cams mixed up. The sprocket is offset differently on each bank, if that's the case it would be both cams that are incorrect. BTW, I'm very intimate with cams because I'm making some right now, it's mind boggling to keep up with the details of each but IIRC the sprockets are offset forward on 1-4 and rearward on 5-8.
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Old Feb 27, 2008 | 01:51 PM
  #45  
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how can you eyball 5mm. someone needs to confirm the placing. if it is correct, then just rotating the cams will allow the tool to fit. there is no way the cams could be reversed, the bearings on the exhaust cam on the driver side is different.

mk
Originally Posted by Mike Simard
Ah, that explains that.
Some random thoughts, if one cam were off a tooth the 113mm would be off by about 4mm at the cast pointers. That doesn't look to be the case.

If the new valve timing was different it could have the tool sitting like that. 10 degrees of valve timing would move the opposite end of the alignment tool 3/8"
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