Generation III Internal Engine 1997-2006 LS1 | LS6
Sponsored by:
Sponsored by:

piston not exactly level side to side

Old Sep 3, 2019 | 02:19 PM
  #1  
patSS/00's Avatar
Thread Starter
TECH Fanatic
20 Year Member
Photogenic
Photoriffic
Liked
iTrader: (6)
 
Joined: Nov 2001
Posts: 1,010
Likes: 17
From: AZ
Default piston not exactly level side to side

I have an LS1 block that's been freshly honed .010 and new flat top pistons. The pistons are all .002-.003 under the deck, but one (#8) is .000 on the left side and .002-.003 on the right side. I'm measuring with a machinists straight edge and feeler gauges. What does this mean? The block deck itself is flat. The opposite piston #7 is level. Is there a spec for this, and should I just ignore it?
Reply
Old Sep 3, 2019 | 02:21 PM
  #2  
Ls7colorado's Avatar
TECH Addict
20 Year Member
Liked
Loved
Community Favorite
iTrader: (3)
 
Joined: Jul 2005
Posts: 2,119
Likes: 610
From: Henderson, TN
Default

the pistons will have a SLIGHT rock to them, try measuring how much each piston will rock side to side
Reply
Old Sep 3, 2019 | 02:27 PM
  #3  
patSS/00's Avatar
Thread Starter
TECH Fanatic
20 Year Member
Photogenic
Photoriffic
Liked
iTrader: (6)
 
Joined: Nov 2001
Posts: 1,010
Likes: 17
From: AZ
Default

Originally Posted by Ls7colorado
the pistons will have a SLIGHT rock to them, try measuring how much each piston will rock side to side
OK, well I thought they could only rock top to bottom, not side to side.

Edit: You are right!! I was able to push down on that side, now got at least .0015 gap on that side.
Thank you!

Should have realized, there couldn't ever be "piston slap" if the pistons couldn't rock side to side.

Last edited by patSS/00; Sep 3, 2019 at 02:45 PM.
Reply
Old Sep 3, 2019 | 03:18 PM
  #4  
Ls7colorado's Avatar
TECH Addict
20 Year Member
Liked
Loved
Community Favorite
iTrader: (3)
 
Joined: Jul 2005
Posts: 2,119
Likes: 610
From: Henderson, TN
Default

no problem!
Reply
Old Sep 12, 2019 | 04:11 PM
  #5  
00pooterSS's Avatar
TECH Veteran
15 Year Member
Photogenic
Liked
Community Favorite
iTrader: (40)
 
Joined: Mar 2008
Posts: 4,920
Likes: 531
From: Dallas
Default

Also, you have to rock them and add the measurements then divide by 2 to get the out of the hole measurement.

Sounded really off when you said they are all in the hole. They shouldn't be, especially if the block was decked.
Reply
Old Sep 12, 2019 | 04:40 PM
  #6  
patSS/00's Avatar
Thread Starter
TECH Fanatic
20 Year Member
Photogenic
Photoriffic
Liked
iTrader: (6)
 
Joined: Nov 2001
Posts: 1,010
Likes: 17
From: AZ
Default

Originally Posted by 00pooterSS
Also, you have to rock them and add the measurements then divide by 2 to get the out of the hole measurement.

Sounded really off when you said they are all in the hole. They shouldn't be, especially if the block was decked.
Block was not decked. The stock pistons were about .007 out of the hole. The new pistons are .010 shorter than stock, so they end up being .003 in the hole.
Both Mahle and Sealed Power replacement flat top pistons are only available as .010 lower compression height compared to the originals. I even called Mahle to verify they no longer make the original stock height pistons, even though they're listed in their catalog.
Reply
Old Sep 12, 2019 | 04:51 PM
  #7  
00pooterSS's Avatar
TECH Veteran
15 Year Member
Photogenic
Liked
Community Favorite
iTrader: (40)
 
Joined: Mar 2008
Posts: 4,920
Likes: 531
From: Dallas
Default

Gotcha. For some reason I thought you said in the first post the block was decked, I just ran **** together that wasn't there apparently.
Reply


Thread Tools
Search this Thread

All times are GMT -5. The time now is 02:47 PM.

story-0
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-1
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-2
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-3
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-4
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-5
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-6
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-7
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE
story-8
Five Reasons the Camaro Was the Most Pivotal Player in the Pony Car Wars 2.0

The world was a better place when it was still around.

By Brett Foote | 2026-01-23 09:20:37


VIEW MORE
story-9
10 Reasons the LS7 Is GM's Most Extreme Naturally Aspirated V8 Engine Ever

Slideshow: The 7.0-liter LS7 was designed for absolute cutting-edge performance.

By Verdad Gallardo | 2026-01-07 18:36:00


VIEW MORE