Break in speeds

[TJC]

The manual says to not drive at any constant speed fast or slow but that's pretty vague. I had a 3 hour highway drive last night and varied between 65-75. Last hour I set the cruise at 72 and ran it up to 76 then let it coast down to 72 every few minutes. I don't know if this is what's expected because its not defined in the manual, gotta say it wasn't the most fun trip constantly slowing down and speeding up.

 

[ellteefour]

Sounds like you did just fine. I wouldn’t overthink it. The other variable you can toss in is varying gear selection for any given speed, but keep in mind lugging it will do far more harm than happening to rev it slightly higher than the 4,000 RPM guideline on occasion.

 

[Champale]

I honestly don't think you are varying the rpm enough. You want to put some load on the engine here and there, say accelerating moderately from 2k to 4k rpm. I would suggest a quick google on why you want to vary revs and put load on the engine in the first few hundred miles. Pistons rings need to seat properly.

 

[ngoni]

Also get in some amount of reasonable engine braking which really seats the rings on a new engine.

 

[ellteefour]

If you skip to 50:47 of this video, the presenter from the BG build team explains why the LT4 long block itself doesn’t really need to be broken in, but the procedure is there for things like the diff, brakes, and a very interesting reason for the supercharger.

 

[TJC]

I don't see the link to the video you refer to.

 

[TJC]

Dufus here didn't notice the link color on my phone.

 

[TJC]

Thanks for that video Merlette. I have 536 miles and the tach went to 6500 redline last night but truth be told I don't think I got into the supercharger too much while keeping it under 4500 rpm.

 

[ellteefour]

Dufus here didn't notice the link color on my phone.

I forgot to underline it. I wish the forum did it automatically!