max bore on 5.3?
03-28-2011, 10:23 AM
#2
If it's an iron 5.3L block, then yes, you can typically go to the LS1 aftermarket piston bore of 3.90x" without any issues!
__________________
Largest Stocking Distributor of LS-x Engines / CHECK OUT OUR NEW WEBSITE!
COMP - FAST - PACESETTER - DIAMOND RACING - EAGLE SPECIALTY PRODUCTS - CALLIES - COMETIC GASKETS
RAM CLUTCHES - MOSER ENGINEERING - KOOK'S HEADERS - ARP - GM BOLTS AND GASKETS - MSD - NGK
POWERBOND - ASP - AND MORE!
Largest Stocking Distributor of LS-x Engines / CHECK OUT OUR NEW WEBSITE!
COMP - FAST - PACESETTER - DIAMOND RACING - EAGLE SPECIALTY PRODUCTS - CALLIES - COMETIC GASKETS
RAM CLUTCHES - MOSER ENGINEERING - KOOK'S HEADERS - ARP - GM BOLTS AND GASKETS - MSD - NGK
POWERBOND - ASP - AND MORE!
03-28-2011, 03:18 PM
#5
I have not had the chance to check an aluminum 5.3L block, but from the little bit of reading I have done it is not going to go as far as the iron. But again, I'd have to check one myself to be sure!
__________________
Largest Stocking Distributor of LS-x Engines / CHECK OUT OUR NEW WEBSITE!
COMP - FAST - PACESETTER - DIAMOND RACING - EAGLE SPECIALTY PRODUCTS - CALLIES - COMETIC GASKETS
RAM CLUTCHES - MOSER ENGINEERING - KOOK'S HEADERS - ARP - GM BOLTS AND GASKETS - MSD - NGK
POWERBOND - ASP - AND MORE!
Largest Stocking Distributor of LS-x Engines / CHECK OUT OUR NEW WEBSITE!
COMP - FAST - PACESETTER - DIAMOND RACING - EAGLE SPECIALTY PRODUCTS - CALLIES - COMETIC GASKETS
RAM CLUTCHES - MOSER ENGINEERING - KOOK'S HEADERS - ARP - GM BOLTS AND GASKETS - MSD - NGK
POWERBOND - ASP - AND MORE!
03-28-2011, 04:40 PM
#7
The only ones i could find that are LS1 and not forged were 3.898" and 3.907"(.25mm oversized) bore. Sealed Power --Speed Pro Hypereutectic Flat-top Pistons at $35.99 And $26.99 each respectively.
Now ya know that the 3rd gen pistons are press fit pins. So the stock rods/pistons of a 3rd gen 5.3L are NOT compatible with a 4th gen. (they are full floating pins/rods).
Im doing what you are thinking about doing!
Trending Topics
03-28-2011, 07:19 PM
#8
What brand and type of pistons are you getting that are made for a 3.903 bore?
The only ones i could find that are LS1 and not forged were 3.898" and 3.907"(.25mm oversized) bore. Sealed Power --Speed Pro Hypereutectic Flat-top Pistons at $35.99 And $26.99 each respectively.
Now ya know that the 3rd gen pistons are press fit pins. So the stock rods/pistons of a 3rd gen 5.3L are NOT compatible with a 4th gen. (they are full floating pins/rods).
Im doing what you are thinking about doing!
The only ones i could find that are LS1 and not forged were 3.898" and 3.907"(.25mm oversized) bore. Sealed Power --Speed Pro Hypereutectic Flat-top Pistons at $35.99 And $26.99 each respectively.
Now ya know that the 3rd gen pistons are press fit pins. So the stock rods/pistons of a 3rd gen 5.3L are NOT compatible with a 4th gen. (they are full floating pins/rods).
Im doing what you are thinking about doing!
The following users liked this post:
txh0tb0i972 (04-27-2023)
03-28-2011, 09:35 PM
#9
I just finished boring a 5.3 out to 4" to make a budget LQ4. Sonic checked the cylinders, and the thinnest I saw anywhere was .095" on a couple of holes along the wristpin axis. Thrust major and minor were all between .160" and .200" give or take a little. What's crazy is that this is still more cylinder wall all the way around than the average SBC 350 at .060" over....
The following users liked this post:
bowtiefresh (12-25-2019)
04-03-2011, 02:50 PM
#14
TECH Apprentice
iTrader: (21)
Join Date: Nov 2007
Location: Albuquerque, New Mexico
Posts: 398
Likes: 0
Received 0 Likes
on
0 Posts
The Gen III aluminum 5.3s I have sonic checked have enough wall thickness for a 3.903 bore. In fact I have a stock bore LS6 block and I have had the block sonic checked along with an LM4 bored to 3.898. The walls sonic checked almost identically. I would certainly sonic check your individual 5.3 to be sure. Something must have changed in the Gen IV 5.3 because I have read and heard that the cylinder walls are not as thick and they can only be bored .006" over the stock bore.
The beauty of an LM4 aluminum 5.3 is that they are the exact same construction as an LS6 block. Same material and same architecture especially in terms of oil breathing vents which is an improvement over the original LS1 design. To best take advantage of boring a 5.3, plan on torque plate honing to the stock 3.898 bore of an LS6. You will have the potential for a superior bore than any used LS6 block you'll encounter AND the block will be seasoned which will be an advantage over a new LS6 block. Additionally, the LM4 block can be purchased for half of what an LS6 block would. There is a little sleeper effect if you show the "5.3" cast into the side.
The beauty of an LM4 aluminum 5.3 is that they are the exact same construction as an LS6 block. Same material and same architecture especially in terms of oil breathing vents which is an improvement over the original LS1 design. To best take advantage of boring a 5.3, plan on torque plate honing to the stock 3.898 bore of an LS6. You will have the potential for a superior bore than any used LS6 block you'll encounter AND the block will be seasoned which will be an advantage over a new LS6 block. Additionally, the LM4 block can be purchased for half of what an LS6 block would. There is a little sleeper effect if you show the "5.3" cast into the side.
04-03-2011, 06:10 PM
#15
The Gen III aluminum 5.3s I have sonic checked have enough wall thickness for a 3.903 bore. In fact I have a stock bore LS6 block and I have had the block sonic checked along with an LM4 bored to 3.898. The walls sonic checked almost identically. I would certainly sonic check your individual 5.3 to be sure. Something must have changed in the Gen IV 5.3 because I have read and heard that the cylinder walls are not as thick and they can only be bored .006" over the stock bore.
The beauty of an LM4 aluminum 5.3 is that they are the exact same construction as an LS6 block. Same material and same architecture especially in terms of oil breathing vents which is an improvement over the original LS1 design. To best take advantage of boring a 5.3, plan on torque plate honing to the stock 3.898 bore of an LS6. You will have the potential for a superior bore than any used LS6 block you'll encounter AND the block will be seasoned which will be an advantage over a new LS6 block. Additionally, the LM4 block can be purchased for half of what an LS6 block would. There is a little sleeper effect if you show the "5.3" cast into the side.
The beauty of an LM4 aluminum 5.3 is that they are the exact same construction as an LS6 block. Same material and same architecture especially in terms of oil breathing vents which is an improvement over the original LS1 design. To best take advantage of boring a 5.3, plan on torque plate honing to the stock 3.898 bore of an LS6. You will have the potential for a superior bore than any used LS6 block you'll encounter AND the block will be seasoned which will be an advantage over a new LS6 block. Additionally, the LM4 block can be purchased for half of what an LS6 block would. There is a little sleeper effect if you show the "5.3" cast into the side.
04-03-2011, 11:35 PM
#16
TECH Apprentice
iTrader: (21)
Join Date: Nov 2007
Location: Albuquerque, New Mexico
Posts: 398
Likes: 0
Received 0 Likes
on
0 Posts
I'm probably just muddying up the waters but apparently it's being done.
http://cgi.ebay.com/ebaymotors/GM-GE...Q5fAccessories
With what success.....who knows.
http://cgi.ebay.com/ebaymotors/GM-GE...Q5fAccessories
With what success.....who knows.
04-13-2011, 06:46 PM
#17
I have a Gen IV 2007 LC9 aluminum engine I pulled the heads off today (fire damage) Im not an engine builder but I can post pics for everyone to see. I was thinking abut selling it, but now I am thinking I can have it bored out to a 3.90X bore and slap in some pistons and be good to go.
I will post pics ASAP if anyone is interested??
I will post pics ASAP if anyone is interested??
04-25-2011, 06:58 PM
#18
Bilster, what kind of ultrasonic tester are you using and where are you checking? How are you calibrating it? I ask, because you didn't clarify whether your results were for overall thickness of the whole cylinder (alum + iron sleeve) or just the iron sleeve. I, personally, get wacky numbers with mine when trying to sonic test ferrous metal that is press fit into aluminum..
Last edited by defrag010; 04-25-2011 at 07:27 PM.
04-25-2011, 11:39 PM
#19
TECH Fanatic
iTrader: (8)
Join Date: Nov 2009
Location: phx the cactus patch
Posts: 1,095
Likes: 0
Received 13 Likes
on
13 Posts
Just to clarify the poster talking about the difference between gen3 and gen4 pin floating ,,,,,, the gen3 and gen4 have a different diameter pin and a different compression height .
04-26-2011, 09:21 AM
#20
TECH Resident
iTrader: (5)
Join Date: Feb 2008
Location: Bardstown, KY
Posts: 963
Likes: 0
Received 0 Likes
on
0 Posts
I just finished boring a 5.3 out to 4" to make a budget LQ4. Sonic checked the cylinders, and the thinnest I saw anywhere was .095" on a couple of holes along the wristpin axis. Thrust major and minor were all between .160" and .200" give or take a little. What's crazy is that this is still more cylinder wall all the way around than the average SBC 350 at .060" over....