Heads for 5.3Liter?
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From: Phoenix, AZ USA
Heads for 5.3Liter? Hey guys, I have a set of 5.3 Liter heads that I baught a while back to dink around with and possibly sell or use. Well last week I baught a 5.3Liter Silverado so now I have a use for these heads. 
I know the 5.3 has a smaller bore than the 5.7 so the question is what size valves do I use? I would LIKE to do a stage 2 setup (2.02"/1.60") but I'm wondering if the bore size would be too tight for that. Any ideas?
I know the 5.3 has a smaller bore than the 5.7 so the question is what size valves do I use? I would LIKE to do a stage 2 setup (2.02"/1.60") but I'm wondering if the bore size would be too tight for that. Any ideas?
On The Tree
Joined: May 2004
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From: TEA
it is best to leave it up to the pros...but if your serious start with a good valve job use a 2.02 intake (ferrea 
) and keep your stock exhaust valves they flow more and are stronger than most after market valves 
GM
if you plan on doing port work (wich it sounds like you do) realize that you will see the most gain of flow in the areas nearest the seat
ohh and be sure not to hit the angle where the seat meets the valve!!
pm me for more details
) and keep your stock exhaust valves they flow more and are stronger than most after market valves GM if you plan on doing port work (wich it sounds like you do) realize that you will see the most gain of flow in the areas nearest the seat
ohh and be sure not to hit the angle where the seat meets the valve!!
pm me for more details
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From: Albuquerque, NM
My understanding is that the bigger valves on the stock truck blocks causes some issues with flow and shielding due to the smaller bore ( 3.78" vs 3.90" ). Maybe check with ARE for more info. You may not realize all the gains with larger valves but I also hear the heads will accept the larger valves with minimal machining.
PS, the 5.3L block can be bored out to the stock LS1 size! I know this for sure and have sonic tests to prove it. Makes for a budget build LS1 and then can accept a stroker kit, too!
PS, the 5.3L block can be bored out to the stock LS1 size! I know this for sure and have sonic tests to prove it. Makes for a budget build LS1 and then can accept a stroker kit, too!
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From: Phoenix, AZ USA
the stock 5.3Liter is a 1.89"/1.55" stock right? Can I just get a set of stock LS1 2.00"/1.55" valves and just do a valve job (or do I need to replace the seats)?
Are all the iron blocks the same (4.8/5.3/6.0)? What is the MAX bore that the iron blocks can take?
Are all the iron blocks the same (4.8/5.3/6.0)? What is the MAX bore that the iron blocks can take?
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From: Albuquerque, NM
The 4.8/5.3 blocks are identical, I have bored mine out to 3.900", which is std LS1 bore. The 6.0L block is capable of +0.060 ( from 4.000" ), to my knowledge, and used with a 4" stroker crank gets displacement up to 427 cubes. You can go bigger with sleeves but for "standard" machine work the 6.0L is the best for maximum displacement.
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From: RainbowCity,Alabama
Originally Posted by 2001CamaroGuy
the stock 5.3Liter is a 1.89"/1.55" stock right? Can I just get a set of stock LS1 2.00"/1.55" valves and just do a valve job (or do I need to replace the seats)?
Are all the iron blocks the same (4.8/5.3/6.0)? What is the MAX bore that the iron blocks can take?
Are all the iron blocks the same (4.8/5.3/6.0)? What is the MAX bore that the iron blocks can take?
You do not have to replace the stock intake seats.
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