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Discussion Starter · #1 ·
Will the crank and rods from a 5.3 work in a 6.0 block?? I know the stroke is the same and the length of the rods are the same but I was unclear if you could interchange them. Also, will the 706 heads that I have be fine on a 6.0. I know the combustion chambers are smaller but I can adjust that with the pistons and head gaskets if needed. Before I get flamed for asking these questions.....I am asking because I have all the other parts (for free) and was going to do forged pistons on the build anyway even if I did a bored out 5.3 up to 5.7 specs. Please let me know.

Rich
 

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haz 12"s!
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Arent eh 706 heads 5.3? The 5.3 has small valves. They will work, but the 6.0 heads have bigger valves.
 

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HOT AIR BALLOON OWNER
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Arent eh 706 heads 5.3? The 5.3 has small valves. They will work, but the 6.0 heads have bigger valves.
Yes, plus the 317 head has better ports to begin with...



If you're going thru that hassle, have rods that have floating wrist pins. Be stupid to get ones resized, balanced, and fitted w/ new hardware that are pressed pin still.
 

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Discussion Starter · #7 ·
I am going to do the best I can with the free parts I get. I have several resources that get me stuff for free so I am going to put together the best engine I can for as little as I can. All my machine work including head work is free.....benefit of having close family friends that own a engine machine shop....with a full dyno setup. Other than buying new pieces for the heads and buying a cam and pistons I can build this engine for no additional costs. So if it ends up being a bored out 5.3 to 5.7 and running these 706 heads with good parts in them I am good with that.

I am going to study the cam sticky because I need a good cam that produces power low to mid and need to know what to get and the best brand. This will be my DD and I tow a small enclosed trailer everyday for my job. I don't want anything radiacal, just something that makes good power and idles nice and smooth. If you have any suggestions let me know. Thanks.

Rich
 

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HOT AIR BALLOON OWNER
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I paid about $60 for some 317 heads.

If the rods you have are pressed pin, just sell them. You can get some stock LS1 rods for cheap online.
 

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HOT AIR BALLOON OWNER
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yes, the rods have pressed pins. Do the LS1 rods have floating pins??


Yeah, so do LS2s, late LQ4s, LQ9s do, etc. They're super common. The later rods ('05? and later) are also stronger in stock form.
 

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HOT AIR BALLOON OWNER
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No prob, keep us updated on the build.
 

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Discussion Starter · #13 ·
I will. I am in no hurry, nothing wrong with the 5.3 in the truck right now. I will accumulate the pieces and then start putting it together. I stripped down the heads tonight and I am going to drop the heads off at the shop tomorrow to get hot tanked and then checked out to make sure they are good. What do you guys suggest for valves???
 

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HOT AIR BALLOON OWNER
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I will. I am in no hurry, nothing wrong with the 5.3 in the truck right now. I will accumulate the pieces and then start putting it together. I stripped down the heads tonight and I am going to drop the heads off at the shop tomorrow to get hot tanked and then checked out to make sure they are good. What do you guys suggest for valves???


Unless you plan crazy high EGTs/RPM, stock valves are fine.
 

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haz 12"s!
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Yes, plus the 317 head has better ports to begin with...



If you're going thru that hassle, have rods that have floating wrist pins. Be stupid to get ones resized, balanced, and fitted w/ new hardware that are pressed pin still.
Yes. The 317 head is a LS6 head with a bigger CC chamber. All else is the same. If youre keeping the stock rods, I would at least get some ARP bolts.

Yeah, so do LS2s, late LQ4s, LQ9s do, etc. They're super common. The later rods ('05? and later) are also stronger in stock form.
Unless something has changed, my LS1 was a pressed pin. They arent floaters since they dont have the locks on the sides of the rod pins.

LS2s are floaters though.. http://www.hotrod.com/techarticles/...s_supercharged_ls1_engine_build/photo_09.html
 

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Discussion Starter · #16 ·
thanks for the opinion on the valves, I was going to ask that question today. On the subject, can I just clean them up, do a valve job and reuse??

I will without question put ARP bolts in what ever rods I use.
 

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haz 12"s!
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Sure you can just do a lap job and be good, but the 5.3 heads will kill your power on the 6.0 having that smaller valves and runners. I'd spend the $100 and grab some stock 6.0s.
 

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HOT AIR BALLOON OWNER
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Hmmmmmmm, I was told the 5.7's were not pressed pin. :shrug:
 

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Discussion Starter · #19 ·
Dropped my heads off to get hot tanked and magnafluxed today. I was able to get my hands on another 5.3 block that is good and ready to be machined for free. Going to have it bored to 5.7 and go from there. Again.....I know a 6.0 would be more power but again I have ZERO dollars spent on this so far....good block, heads, crank, rods, free machine work. Good to know the right people.
 
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