Engine Build Questions
Thread Starter
Launching!
Joined: Apr 2013
Posts: 225
Likes: 0
Engine Build Questions I have a few questions about building an LS based egnine, but first here is where things are.
Sometime in February I took my engine to the machine shop.
It needed to be bored. It is also getting rebuilt as a 5.3L.
I understand that for this I needed a new crank and rods, they told me they have a 5.3 crank but no rods. The price they insisted that a used set of 5.3 rods, and reconditioning would cost it was about 100$ more to get a set of forged rods, so I chose to do that.
Since then I don't think anything has been done.
When I stopped in on 5/12/2013 I was told something about the pistons needing to be bored .002 to fit the wrist pins that were needed as the GM style wrist wont fit the rods.
I stopped in again yesterday (5/20/2014), and nothing more had been done.
I have serious doubts that half of what they are telling me is correct.
I don't have part numbers for this right now I need to get them.
Sometime in February I took my engine to the machine shop.
It needed to be bored. It is also getting rebuilt as a 5.3L.
I understand that for this I needed a new crank and rods, they told me they have a 5.3 crank but no rods. The price they insisted that a used set of 5.3 rods, and reconditioning would cost it was about 100$ more to get a set of forged rods, so I chose to do that.
Since then I don't think anything has been done.
When I stopped in on 5/12/2013 I was told something about the pistons needing to be bored .002 to fit the wrist pins that were needed as the GM style wrist wont fit the rods.
I stopped in again yesterday (5/20/2014), and nothing more had been done.
I have serious doubts that half of what they are telling me is correct.
I don't have part numbers for this right now I need to get them.
Well, why did it need to be bored? If you were boring it, you should have just punched it out to a 5.7L 3.9" bore.
You don't need new rods or a new crank to bore the motor and rebuild. Most rebuilds are just bore/hone, align mains if needed, magnaflux/hot tank for the iron block, and new bearings, and rings along with the blue printing of all clearances. You can clean up a crank and use .010" oversized bearings if you turn it down a bit to clean it up. Same for the rods and then you can put ARP bolts in there and they would be fine.
Also, I'm not sure about needing to bore the piston out to fit the wrist pin, unless they are trying to use a press fit pin piston in a floating pin design rod. It's a .945" vs .927" in those pin designs.
The only other thing I can think of is .002" oversize for the rod bearings if they are stock rods and it went out of round and needed to be honed.
Basically, I would get a detailed work order from them listing the labor and parts. I would not allow them to work on the motor or pay them anything until that bill of materials/labor was agreed upon in writing. Then you can ask questions.
Also, a simple 5.3L rebuild shouldn't take 3 months. 2-3 weeks depending on how backed up they are...
Also, if they are not used to the LS1, I would have some concern over the build.
You don't need new rods or a new crank to bore the motor and rebuild. Most rebuilds are just bore/hone, align mains if needed, magnaflux/hot tank for the iron block, and new bearings, and rings along with the blue printing of all clearances. You can clean up a crank and use .010" oversized bearings if you turn it down a bit to clean it up. Same for the rods and then you can put ARP bolts in there and they would be fine.
Also, I'm not sure about needing to bore the piston out to fit the wrist pin, unless they are trying to use a press fit pin piston in a floating pin design rod. It's a .945" vs .927" in those pin designs.
The only other thing I can think of is .002" oversize for the rod bearings if they are stock rods and it went out of round and needed to be honed.
Basically, I would get a detailed work order from them listing the labor and parts. I would not allow them to work on the motor or pay them anything until that bill of materials/labor was agreed upon in writing. Then you can ask questions.
Also, a simple 5.3L rebuild shouldn't take 3 months. 2-3 weeks depending on how backed up they are...
Also, if they are not used to the LS1, I would have some concern over the build.
Thread Starter
Launching!
Joined: Apr 2013
Posts: 225
Likes: 0
I bought the engine as a 5.3l with about 100k miles. It turned out to be a a 4.8l with high miles. The cylinders were out of round.
It was not explained well before.
The rods are eagle forged and use a .945 pin.
The pistons are for a 2007 5.3 with flat tops.
It was not explained well before.
The rods are eagle forged and use a .945 pin.
The pistons are for a 2007 5.3 with flat tops.
The 2007 5.3 pistons are floating pin... so that's why they are having to machine to fit the Eagle rods.
So the bore is the same between the 4.8 and 5.3. It should just require a light hone. The stroke is different between the two.
Sounds like what they are doing is correct... who bought the rods?
So the bore is the same between the 4.8 and 5.3. It should just require a light hone. The stroke is different between the two.
Sounds like what they are doing is correct... who bought the rods?
Thread Starter
Launching!
Joined: Apr 2013
Posts: 225
Likes: 0
They did, but only after I asked for them after finding out the price difference from getting used rods, reconditioning them, and good new bolts.
I knew that this was a smaller machine shop, but I found out that it is smaller then I thought it was. There are normally 2 people there, and it is also the most recommended machine shop in the area.
EDIT
Basically a smaller shop with more work then I was thinking.
I knew that this was a smaller machine shop, but I found out that it is smaller then I thought it was. There are normally 2 people there, and it is also the most recommended machine shop in the area.
EDIT
Basically a smaller shop with more work then I was thinking.
Thread Starter
Launching!
Joined: Apr 2013
Posts: 225
Likes: 0
Still in the shop. It seems their parts supplier keeps sending them the wrong parts.
Any advice for fuel injector selection? It turns out the injectors I have will not work.
Is it common to have problems with used LS injectors?
Any advice for fuel injector selection? It turns out the injectors I have will not work.
Is it common to have problems with used LS injectors?
Trending Topics
I would say no it is not common to have problems with LS based gen 3/4 chevy small block v-8's fuel injectors . Nor any GM engines injectors that I'm aware of with the exception of maybe a small engine actually made by someone else if GM even does that any more .
Last edited by chrisfrost; Jun 7, 2014 at 05:14 AM. Reason: forgot a thing or two
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
