Line bore off 4 thousandths
Thread Starter
Teching In
Joined: Feb 2016
Posts: 30
Likes: 16
Line bore off 4 thousandths I sent a LQ4 block to my machine shop and he called me this afternoon saying the line bore is off 4 thousands. He asked if I was sure they were the right Main caps because the block is bead one, but the caps are what are off he is saying. The mains were marked but I bought the motor as a bare block so I am wondering if they put different mains on it before I bought it. Would you suggest line boring and not shaving off of the main caps. Or shaving 2 thousandths or more off of the main caps, and line bore after that.
I assume it’s .004” too big?
Maybe it spun bearings. Or got way to hot. Or the caps came from a diff block.
These things require effort to align hone properly. The cap sides aren’t very parallel so are tough to fixture for cutting the mating surface.
I’d use the other block.
Maybe it spun bearings. Or got way to hot. Or the caps came from a diff block.
These things require effort to align hone properly. The cap sides aren’t very parallel so are tough to fixture for cutting the mating surface.
I’d use the other block.
TECH Addict
Joined: Dec 2017
Posts: 2,191
Likes: 978
Somebody just asked this in the last couple of days, in the forum appropriate to the LQ4. Good wisdom in this post.
https://ls1tech.com/forums/generatio...y-options.html
One post in one forum for one subject is usually enough.
Even if people don't tell you what you want to hear there.
https://ls1tech.com/forums/generatio...y-options.html
One post in one forum for one subject is usually enough.
Even if people don't tell you what you want to hear there. Trending Topics
Align bore..... As a tool and diemaker of over 40 years, if it was mine, I'd go for an align BORE, NOT an align hone. Reason being.that if the block's OK, the machinist should be able to skin a few thousandths off the caps, bolt them in, and re-bore them to match the block. An align hone, or most any hone, tends to follow the bore more than a boring bar would. The boring bar will cut the new diameter to the block exactly as it should be. Just my .02. COULD be the align hone can correct for only .002" also. What matters most is who does the set-up, and the actual machining. Good luck......
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?
Pouria Savadkouei
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
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 As a tool and diemaker of over 40 years, if it was mine, I'd go for an align BORE, NOT an align hone. Reason being.that if the block's OK, the machinist should be able to skin a few thousandths off the caps, bolt them in, and re-bore them to match the block. An align hone, or most any hone, tends to follow the bore more than a boring bar would. The boring bar will cut the new diameter to the block exactly as it should be. Just my .02. COULD be the align hone can correct for only .002" also. What matters most is who does the set-up, and the actual machining. Good luck......
As a tool and diemaker of over 40 years, if it was mine, I'd go for an align BORE, NOT an align hone. Reason being.that if the block's OK, the machinist should be able to skin a few thousandths off the caps, bolt them in, and re-bore them to match the block. An align hone, or most any hone, tends to follow the bore more than a boring bar would. The boring bar will cut the new diameter to the block exactly as it should be. Just my .02. COULD be the align hone can correct for only .002" also. What matters most is who does the set-up, and the actual machining. Good luck......
40+ years means something...... I’m going to disagree here with you. Line boring is a totally different process, is time consuming and expensive, it’s usually done when main caps are changed and there is a lot of metal to remove. .004” can easily be fixed with a line hone process. Not many machine shops can line bore, almost all can line hone.
