C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
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Old Nov 29, 2007 | 11:44 PM
  #41  
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Originally Posted by Scott Marzahl
SRP makes a -16 cc forged piston for a 383.
The -16 gives me a 9.99CR. Too high.

Need the -20 or the -21 mentioned. I still don't understand who the mfg. and part number is for the -21.
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Old Nov 30, 2007 | 12:55 AM
  #42  
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Why don't you set it up on the tight side, then open up the combustion chambers to hit the compression numbers you want? Like Matt said, it will help with shrouding around the valves. This is the essence of hot rodding.

BigBlockk

Later.....
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Old Nov 30, 2007 | 06:30 AM
  #43  
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When they did the valves they unshrouded the area behind them. I would have to remove an additional 3 cc's from each cylinder. From what I understand if you take material away from the wrong places you can hurt flow. Not to mention the possibility of hitting a water jacket and thereby trashing my numbers matching heads. So basically I don't know how. I would have the machine shod do it but it would cost me more than the right sized -20 Weisco forged pistons would.

If I could only find a -19, -20, or, -21 hypo piston.
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Old Nov 30, 2007 | 11:10 AM
  #44  
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Originally Posted by AWilson
When they did the valves they unshrouded the area behind them. I would have to remove an additional 3 cc's from each cylinder. From what I understand if you take material away from the wrong places you can hurt flow. Not to mention the possibility of hitting a water jacket and thereby trashing my numbers matching heads. So basically I don't know how. I would have the machine shod do it but it would cost me more than the right sized -20 Weisco forged pistons would.

If I could only find a -19, -20, or, -21 hypo piston.
KB has a -18cc piston, but I opted for the -23 rather than use the -18 because I wanted to stay away from the KB pistons.
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Old Nov 30, 2007 | 02:45 PM
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Originally Posted by dgruenke
KB has a -18cc piston, but I opted for the -23 rather than use the -18 because I wanted to stay away from the KB pistons.
Thats exactly how and why I found the -23 too. Too much controversy on the KB's for me to decide so if I stayed away from them I didn't have to decide. But I tend to believe there is nothing wrong with them. People just need to follow the instructions and gap the rings properly. But what do I know.

Still need a hyper -19, -20,or -21 or I'm gonna buy the forged Weisco's
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