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engine block rebuilding question for the experts

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Old 09-12-2005, 04:32 PM
  #31  
m21sniper
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The last two pix are exactly what you'd want on an iron block or steel sleeved engine, a nice light crosshatching pattern.
Old 09-12-2005, 05:08 PM
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Needs to be polished then silicon treated according to the books.
Old 09-12-2005, 05:13 PM
  #33  
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Mark,
Based on the look, and the relation to the "scratch", it actually looks "ok". Dinan did htis to the old 850 as recommended by the "flex hone" folks .... forget the company name.

The dull sheen of the Si is still present and it is "unlikely" that any metal to metal contact will occur.

Would I use this block ...No ... i would run the pistons up and down, turn the crank by hand or with a "big drill" with some auto trans fluid and see if the surface improves.

Marc
Old 09-12-2005, 05:18 PM
  #34  
mark kibort
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Thanks Marc,

I really appreciate the input here on this one. (and so does scot, but he doesnt know it yet.)

Mark

Originally Posted by marc@DEVEK
Mark,
Based on the look, and the relation to the "scratch", it actually looks "ok". Dinan did htis to the old 850 as recommended by the "flex hone" folks .... forget the company name.

The dull sheen of the Si is still present and it is "unlikely" that any metal to metal contact will occur.

Would I use this block ...No ... i would run the pistons up and down, turn the crank by hand or with a "big drill" with some auto trans fluid and see if the surface improves.

Marc
Old 09-13-2005, 11:21 PM
  #35  
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Bore it to make a 5.0 liter!
Old 08-20-2009, 09:55 AM
  #36  
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Hi, I stumbled across your forum and found this thread so I've just joined so as to comment here if that's ok. The blocks are alusil throughout so the silicone is impregnated throughout the aluminium. Once you have roughed up etc with the various stones you use felt pads coated with silicone paste . The hard silicone in the paste rips out aluminium from around the silicon granules in the block thus leaving the silicon proud of the aluminium. The piston/rings will ride on the silicone. When this has been done properly the bore has a matt grey appearance and feels smooth as glass. It's possible to save blocks that have only light scuffing this way and still remain within porsche tolerences. HTH. Mike. Oh, it's a messy process but I've saved a few blocks this way!
Old 08-20-2009, 10:14 AM
  #37  
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What were you searching for that popped up this thread?
Old 08-20-2009, 10:30 AM
  #38  
AO
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Don't pay attention to Hacker. His gay lover just left him and he's looking for a new stud.
Old 08-20-2009, 11:22 AM
  #39  
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Originally Posted by Andrew Olson
Don't pay attention to Hacker. His gay lover just left him and he's looking for a new stud.
I said I was sorry, what more do you want from me?????
Old 08-20-2009, 11:50 AM
  #40  
GlenL
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Please, guys, could you keep your spat in "Alternative lifestyles?"
Old 08-20-2009, 11:52 AM
  #41  
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Originally Posted by GlenL
Please, guys, could you keep your spat in "Alternative lifestyles?"
No way, I'm not going anywhere near the 997 forum.
Old 08-21-2009, 05:12 PM
  #42  
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Originally Posted by Hacker-Pschorr
What were you searching for that popped up this thread?
The new ls7 race engine's reputed to be non linered (unlike the road variants). I was trying to find any information suggesting it may be an alusil block given that it's known to be aluminium. By going unlined they'll have more strength between the bores. Searches brought me here
Old 08-21-2009, 07:20 PM
  #43  
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Originally Posted by Boosted ls1
The new ls7 race engine's reputed to be non linered (unlike the road variants). I was trying to find any information suggesting it may be an alusil block given that it's known to be aluminium. By going unlined they'll have more strength between the bores. Searches brought me here
I talked to my friend who has this kind of info

"The LS7R that the GT1 car used was sleeved, and now that they are in GT2 all
they did was de-stroke the motor (from 7 liters to 6), same block less
cubes."

No info that he can share on next years all new 5.5 liter.
Old 08-21-2009, 08:00 PM
  #44  
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Thanks for that. Originally I'd been looking here:

http://www.corvetteracing.com/cars/c...ne_specs.shtml

I've been reading about the possibility of the 5.5 litre on the same forum.
Old 08-22-2009, 09:31 PM
  #45  
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I love those LS blocks. They are so tiny with so many cubes.


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