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LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Piston Selection.

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Old 03-02-2009, 12:34 PM
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Default Piston Selection.
Alright guys. I've got my crank and rods squared away. Now its time for pistons. Whats a good forged piston that'll handle a 250 shot. also rings?
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Old 03-02-2009, 12:46 PM
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Originally Posted by BlackTA96
Alright guys. I've got my crank and rods squared away. Now its time for pistons. Whats a good forged piston that'll handle a 250 shot. also rings?
JE or Wiseco forged aluminum pistons.
Flat tops w/ valve reliefs (for NA)
4.030" (assuming you are boring .030" over)

Someone will chime in with suggestions.
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Old 03-02-2009, 12:52 PM
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So what static comp ratio would i be looking at with a flat top piston?
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Old 03-02-2009, 01:05 PM
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Originally Posted by BlackTA96
So what static comp ratio would i be looking at with a flat top piston?
Need head volume, stroke, bore, deck height, piston valve relief, and head gasket thickness to determine a ballpark SCR.
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Old 03-02-2009, 01:32 PM
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3.75 Crank
6" rod
4.030
stock head volume and deck height.(head volume is I believe 58cc? not sure on deck height)
head gasket is not yet bought.
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Old 03-02-2009, 02:39 PM
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Originally Posted by BlackTA96
3.75 Crank
6" rod
4.030
stock head volume and deck height.(head volume is I believe 58cc? not sure on deck height)
head gasket is not yet bought.
Stock heads are 58cc, stock deck height is anywhere from .020" to .030" (reports of being slightly varied).

Using a piston with a -5cc relief and stock head gasket, you're around 10.8:1. Stepping up to the Impala head gasket (.029") will result in 11.5:1.

But keep in mind that SCR is just an arbitrary number - you should be more interested in your DCR.
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Old 03-02-2009, 03:19 PM
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I like SRP and have never had a problem with them. It depends on your budget. RamAir is right about SCR and DCR. Your dynamic is the number you want to work with.
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Old 03-02-2009, 03:51 PM
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Yea. Im gonna talk over my dynamic with AI when i get my custom cam. Figure if I get a ball park of 11.5:1 or so static that I can work with AI to the dynamic where I want it.
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Old 03-02-2009, 04:43 PM
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For a 250 shot you need a tooled steel top ring, like a Hellfire.
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Old 03-02-2009, 05:26 PM
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built mine to handle a 300 shot. used je nitrous pistons w/tool steel pins and hell fire rings.
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Old 03-02-2009, 05:33 PM
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Originally Posted by grn95t/a
built mine to handle a 300 shot. used je nitrous pistons w/tool steel pins and hell fire rings.
Good to know what I'll need to use...
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Old 03-05-2009, 08:46 AM
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How much did you pay for those je nitrous pistons??
I can't seem to find them.
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Old 03-05-2009, 09:59 AM
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they were right at 800.00 for the pistons and 125.00 for the wrist pins. so 925.00 basicly. my engine builder buys je direct. so i'll try and get a series name, ie; 23* extreme duty flat top, etc...
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Old 03-05-2009, 11:22 AM
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alright. sounds good. thanks man
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