LS3 engine break in process
Burning Brakes
Joined: Dec 2011
Posts: 876
Likes: 116
From: HOMESTEAD FL
Im a firm beleiver in WOT break-in's on new engines.
I drive my cars/trucks hard from day one!
The biggest problem is that most new cars already have several miles on them by the time they arrive... so the "effective" break-in window is long gone by the time we ever get behind the wheel. But over time cylinder sealing does improve with hard WOT driving.
The engines that I have driven the hardest (WOT when new) have always lasted the longest, made the most power, gotten the best MPG and burned the least amount of oil.
Google "Engine break in" ... Here are a few:
NTNOA ENGINE BREAKIN
AMSPERFORMANCE ENGINE BREAKIN
MOTOTUNEUSA BREAKIN
SPEED SAFE, AIR RAM
I drive my cars/trucks hard from day one!
The biggest problem is that most new cars already have several miles on them by the time they arrive... so the "effective" break-in window is long gone by the time we ever get behind the wheel. But over time cylinder sealing does improve with hard WOT driving.
The engines that I have driven the hardest (WOT when new) have always lasted the longest, made the most power, gotten the best MPG and burned the least amount of oil.
Google "Engine break in" ... Here are a few:
NTNOA ENGINE BREAKIN
AMSPERFORMANCE ENGINE BREAKIN
MOTOTUNEUSA BREAKIN
SPEED SAFE, AIR RAM
Last edited by AIR_RAM; Apr 22, 2014 at 08:31 PM.
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Every engine I built, I would go out and hit 5k rpm in 2nd, 3rd, 4th, slow down and do it again, 2-3 times, then drain the oil and its good to go
The rings expand under hi pressure and conform to the piston wall ID each time you pressurize the cylinder with heavy acceleration.
If you baby it, the hi spot on the rings get worn down, then eventually when you wot, the rings expand and they become smaller due to the worn off spots.
The rings expand under hi pressure and conform to the piston wall ID each time you pressurize the cylinder with heavy acceleration.
If you baby it, the hi spot on the rings get worn down, then eventually when you wot, the rings expand and they become smaller due to the worn off spots.
Team Owner
Joined: Sep 2000
Posts: 25,015
Likes: 2,709
From: Far NW 'burbs of Chicago
St. Jude Donor '13
But that's just the Owner Manual, what would those guys know about the car?
(sarcasm)
Race Director
Joined: Sep 2007
Posts: 16,557
Likes: 2,108
From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
The new car break-in is for all components and one that stands out a lot is the differential, since that is tied directly to mileage. Transmission gears are also a concern during their initial wear. Some say most of the engine break-in wear has already happened by the time the dealer has finished the new car prep.
My car had 9 miles on it, even though I had ordered it. Unless it was randomly pulled for a quality road check at BG, then someone at the dealer had their own personal test drive. I wish I would have checked the average speed and MPG before I ever started the engine.
My car had 9 miles on it, even though I had ordered it. Unless it was randomly pulled for a quality road check at BG, then someone at the dealer had their own personal test drive. I wish I would have checked the average speed and MPG before I ever started the engine.
Thread Starter
Advanced
Joined: Feb 2006
Posts: 63
Likes: 0
The new car break-in is for all components and one that stands out a lot is the differential, since that is tied directly to mileage. Transmission gears are also a concern during their initial wear. Some say most of the engine break-in wear has already happened by the time the dealer has finished the new car prep.
My car had 9 miles on it, even though I had ordered it. Unless it was randomly pulled for a quality road check at BG, then someone at the dealer had their own personal test drive. I wish I would have checked the average speed and MPG before I ever started the engine.
My car had 9 miles on it, even though I had ordered it. Unless it was randomly pulled for a quality road check at BG, then someone at the dealer had their own personal test drive. I wish I would have checked the average speed and MPG before I ever started the engine.
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Team Owner
Joined: Sep 2000
Posts: 25,015
Likes: 2,709
From: Far NW 'burbs of Chicago
St. Jude Donor '13
I understand that the break in recommend by the owners manual concerns other components too. In this case, the car is not new, just the replacement LS3. Vehicle is used as a daily driver with an occasional HPDE. Naturally I want have fun with it but I want to make sure it has a proper break-in, and especially prior to running an HPDE.
Can you tell us what went wrong, what kind of LS3 you got, who paid for it, etc?
Thanks.
Burning Brakes
Joined: Dec 2011
Posts: 876
Likes: 116
From: HOMESTEAD FL
I understand that the break in recommend by the owners manual concerns other components too. In this case, the car is not new, just the replacement LS3. Vehicle is used as a daily driver with an occasional HPDE. Naturally I want have fun with it but I want to make sure it has a proper break-in, and especially prior to running an HPDE.
- The first time you fire it up... I tend to have the vehicle parked ready to drive straight out...
- Let it idle to running temperature (190-200 water / 140+Oil)
- Monitor oil pressure/oil temps, Fuel Pressures, Coolant temps
- Look for any leaks or issues and address them while its warming up.
- Once temps are reached dive WOT "ASAP" shifting at 6000RPMs 1st, 2nd & 3rd
- Shift into Nutral and Coast/bring to stop
- Perform this 5-6 times. (The more the better)
- Break-in complete.
- Drive hard for the first 500 miles... like you stole it! The harder you drive it early on the better!
This is basically how I have broke in every engine I have built.
SPEED SAFE, AIR RAM
Last edited by AIR_RAM; Apr 23, 2014 at 05:32 PM.
Race Director
Joined: May 2004
Posts: 16,667
Likes: 1,209
From: Raleigh, NC
St. Jude Donor '15
Most things I have read say drive it pretty hard, but also to make sure to do some deceleration from higher RPM's, i.e. accelerate up to a high RPM, then let off the gas and let it decelerate slowly which would be creating a lot of vacuum in the process. Supposedly this is good for the rings
This is the only way I've done it, and I've gotten rings in an alusil engine to seal, so I guess that's a good thing
I doubt there's much of a wrong way anymore
This is the only way I've done it, and I've gotten rings in an alusil engine to seal, so I guess that's a good thing
I doubt there's much of a wrong way anymore
Safety Car
Joined: Apr 2010
Posts: 4,231
Likes: 451
From: Maryland
You won't go wrong following the manufacture break-in recommendations, I did. Who would know best?
The only change that I made was to change the oil at 1,000 the first time, then at 3,000 and every 5,000 miles from there on.
It won't hurt anything changing the oil sooner except your wallet!
PS: This approach has not hurt the performance from my results. The car does not use a drop of oil and I do run it hard "often". Mobil 5/30 and Delco filter.
The only change that I made was to change the oil at 1,000 the first time, then at 3,000 and every 5,000 miles from there on.
It won't hurt anything changing the oil sooner except your wallet!
PS: This approach has not hurt the performance from my results. The car does not use a drop of oil and I do run it hard "often". Mobil 5/30 and Delco filter.
Last edited by C7/Z06 Man; Apr 24, 2014 at 05:03 AM.
Le Mans Master
Joined: Oct 1999
Posts: 8,205
Likes: 40
From: Tucson AZ
Also remember that "break-in" is for the entire drive train, not just the engine.
Melting Slicks
Joined: Oct 2009
Posts: 2,259
Likes: 1
From: Las Vegas NV
St. Jude Donor '10
I just had the LS3 out of my 08 balanced/blueprinted with new seals, bearings, ARP, and all the bolt-ons. (Converted back n/a from an ECS blower car)
I asked him about recommended break-in and he told me to basically just flog the snot out of it for 500 miles with a good break-in oil. That it wasn't so much about the rpms it reaches, but more about extended engine braking/decel that helps seat the rings properly.
About 2k miles on it now after swapping in fresh oil...not a drop in the intake and no smoke or vapors in the exhaust. Good to go.
I asked him about recommended break-in and he told me to basically just flog the snot out of it for 500 miles with a good break-in oil. That it wasn't so much about the rpms it reaches, but more about extended engine braking/decel that helps seat the rings properly.
About 2k miles on it now after swapping in fresh oil...not a drop in the intake and no smoke or vapors in the exhaust. Good to go.