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924/931/944/951/968 Forum Porsche 924, 924S, 931, 944, 944S, 944S2, 951, and 968 discussion, how-to guides, and technical help. (1976-1995)
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Can you identify this cylinder head?

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Old 08-16-2011, 11:09 PM
  #16  
Paulyy
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It's not the 924 CGTP (944LM) engine is it? i know that was a 2.5L twin cam
Old 08-16-2011, 11:23 PM
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Reimu
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Well that girdle holding the cams isn't normal, at least I don't recall it being but I've only glanced at a couple of 16v heads. I don't see the variocam computer stuff either...
Old 08-16-2011, 11:50 PM
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V2Rocket
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944S head, based on what little of the coolant jacket is visible
Old 08-17-2011, 12:10 AM
  #19  
Van
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Well, it doesn't have a vario-cam solenoid installed... I'm curious about what all the dowel pins are for on the intake ports. I know those don't exist on either an S2 or 968 head.

Your cams have removable sprockets, that's different. I also see that your tensioner isn't hydraulically actuated. Presumably with the new cam girdles and a fixed tensioner, you're aiming for every high RPM. I also see the turbo oil port on the balance shaft cover, but it looks "home made", making me think it wasn't originally a turbo block.
Old 08-17-2011, 01:15 AM
  #20  
michaelmount123
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Ah, Van. You're my man so far. You're clearly familiar with the Porsche 4V head, and you're picking up detail. A few hints: The chain sprockets are removable, but they're also adjustable. So their real purpose is to be able to adjust both intake and exhaust cam timing. You also picked out the mechanical tensioner and the girdles. Moderately high RPM (8000), but the real purpose is to stabilize the valve train with very aggressive cam profiles. You also caught the oil bung on the (empty) balance shaft cover. It's not a turbo feed, it's simply the source of oil pressure for data acquisition. Keep going; you're good.

Think a little more about the dowels.... what are they typically used for?
Old 08-17-2011, 01:24 AM
  #21  
michaelmount123
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Are the cams a little long? Why?
Old 08-17-2011, 07:37 AM
  #22  
Van
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Well, dowel pins are used for alignment, so I suppose you're doing individual throttle bodies/manifolds (or at least 3 separate ones, since the middle two shares a stud) and you want to keep alignment for the porting you've done.

Hmm... longer cams? The S2 doesn't have that bearing journal after the #4 lobes, does it? I assume that's for additional support, too. I actually don't know that much about the 16v heads - do they all have those bearing surfaces on the back, or did you have to put those in? If they have them, why didn't Porsche take advantage of it and make the cams longer?

Last edited by Van; 08-17-2011 at 08:39 AM. Reason: Updated 'cause I figured out the long cams...
Old 08-17-2011, 10:22 AM
  #23  
V2Rocket
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Originally Posted by Van
If they have them, why didn't Porsche take advantage of it and make the cams longer?
iirc they are similar casting to the 928 heads that would be flipped around, so the driven cam would be on the other side
Old 08-17-2011, 10:58 AM
  #24  
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This is awesome.


Old 08-17-2011, 11:42 AM
  #25  
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Default What's the head?

Still no one's identified the head. 944S, S2, 968? Why?
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Old 08-17-2011, 12:43 PM
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im going to go with 968 head, because i think i see a casting date of 1994.
Old 08-17-2011, 12:49 PM
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JohnKoaWood
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Originally Posted by michaelmount123
Still no one's identified the head. 944S, S2, 968? Why?
Perhaps the oil jets for the chain are throwing eveyone off, or the reliefs cut for cam clearance?

It is NOT an S head (wrong casting number), only 1 stud/bolt for fastening the forward coolant passage..

Its an S2 head (no 3rd moutning boss near the chain tensioner, to the rear, unless it was machined off).

Do I also spy port matching (for the ITB setup)?

Looks very nice... but will it run?
Old 08-17-2011, 12:52 PM
  #28  
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Originally Posted by JohnKoaWood
Looks very nice... but will it blend?
FIFY
Old 08-17-2011, 01:01 PM
  #29  
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First, excuse my ignorance but what's 'iirc' and what's 'FIFY'. I feel illiterate.

Good eye, JohnKoaWood, you picked up some detail. Oh BTW, it's not a S2 head. What doya mean 'will it run'? I certainly hope so; too expensive for a lamp like Spencer's.
Old 08-17-2011, 01:06 PM
  #30  
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Originally Posted by michaelmount123
First, excuse my ignorance but what's 'iirc' and what's 'FIFY'. I feel illiterate.

Good eye, JohnKoaWood, you picked up some detail. Oh BTW, it's not a S2 head. What doya mean 'will it run'? I certainly hope so; too expensive for a lamp like Spencer's.
IIRC = If I Remember Correctly
FIFY = Fixed it For You

NOT an S2 head... then an S head with plenty of work done.. I guess you like heavy breathing..

Big valves, ITB, high reving... that should prove to be one hell of a 2.5 (2.8?? PLEASE tell me this is a 2.8) race motor.. If left at 2.5L I am guessing that it is being prepped for a class limited by displacement?


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