help with 427 build please
08-30-2011, 10:27 PM
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Launching!
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help with 427 build please I apologize to start with as I'm typing this on my cell phone. My buddy's h/c ls1 spun a rod bearing (my old car...suck!) and he's looking to upgrade to more cubes now.
As it sits now it's gotta 224/228 .595/578 111 cam with Tsp's stg 2.5 ported 5.3L heads which have 64cc chambers and running patriot gold dual springs...stock lifters, rockers, and choromoly 7.400 pushrods
The goal is to reuse ls6 manifold and heads and cam and everything else but get a 427 ls2 from erlperformance. They quote their na shortblock as 11.5:1 CR and FI shortblock as 9.7:1. Obviously I don't know how they got those numbers cause they don't state what heads were used and chamber size or gasket thickness.
I know you can get a custom CR for an extra $320 which all that is is the piston...but what should I be looking for piston dish wise to keep around 11.5:1 CR so he can still run pump gas?
I know we'll be running graphite head gaskets which have a compressed thickness of .054". I know the 5.3L heads chambers are 64cc's. Ptv with the said cam was minimal on the stock flattop piston with no flycutting so with the new pistons needing to be dished some ptv should be fine.
Can anyone help me identify what size -cc dished piston is needed? I'll pull the bore/stroke off their site now and edit this post.
As it sits now it's gotta 224/228 .595/578 111 cam with Tsp's stg 2.5 ported 5.3L heads which have 64cc chambers and running patriot gold dual springs...stock lifters, rockers, and choromoly 7.400 pushrods
The goal is to reuse ls6 manifold and heads and cam and everything else but get a 427 ls2 from erlperformance. They quote their na shortblock as 11.5:1 CR and FI shortblock as 9.7:1. Obviously I don't know how they got those numbers cause they don't state what heads were used and chamber size or gasket thickness.
I know you can get a custom CR for an extra $320 which all that is is the piston...but what should I be looking for piston dish wise to keep around 11.5:1 CR so he can still run pump gas?
I know we'll be running graphite head gaskets which have a compressed thickness of .054". I know the 5.3L heads chambers are 64cc's. Ptv with the said cam was minimal on the stock flattop piston with no flycutting so with the new pistons needing to be dished some ptv should be fine.
Can anyone help me identify what size -cc dished piston is needed? I'll pull the bore/stroke off their site now and edit this post.
08-30-2011, 10:32 PM
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Launching!
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4.070 bore / 4.125 stroke
I see that's on the ls3 block though for the 427. I'll confirm with my buddy that they're using a ls2 or ls3 block cause the ls2 block listed online anyway shows on 421 cubes with 4.030 bore and 4.125 stroke.
I see that's on the ls3 block though for the 427. I'll confirm with my buddy that they're using a ls2 or ls3 block cause the ls2 block listed online anyway shows on 421 cubes with 4.030 bore and 4.125 stroke.
