cam run in
Thread Starter
Instructor
Joined: Jun 2004
Posts: 233
Likes: 0
From: algonac michigan
cam run in
how long is the accepted time to break in a cam before you can rev/drive the engine normally?
have heard 20 min at idle then drive normally.
when can you open her up?
have heard 20 min at idle then drive normally.
when can you open her up?
Race Director
Joined: Sep 1999
Posts: 11,360
Likes: 382
From: Plano TX
A flat tappet cam needs to be broken in at 2000 rpm. Idle will kill it!
About 20-30 minutes at 2000 rpm and it is fine. You can step on it after that. This is assuming the cam was the only thing replaced. A rebuilt/new short block needs a few hundred miles before you beat on it too much.
A roller cam requires no break in at all.
About 20-30 minutes at 2000 rpm and it is fine. You can step on it after that. This is assuming the cam was the only thing replaced. A rebuilt/new short block needs a few hundred miles before you beat on it too much.
A roller cam requires no break in at all.
Race Director
Joined: Mar 2001
Posts: 11,322
Likes: 1
From: Living in the Hartland
Originally Posted by 76REDSTINGER
how long is the accepted time to break in a cam before you can rev/drive the engine normally?
have heard 20 min at idle then drive normally.
when can you open her up?
have heard 20 min at idle then drive normally.
when can you open her up?
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
Run it between 1500-2000 rpm for 20-30 min. Change the oil, that moly lube is gonna gum your oil filter up.
You can't idle it because you need oil to get to the cam during break in... otherwise... :-/
-Steve
You can't idle it because you need oil to get to the cam during break in... otherwise... :-/
-Steve
Pro
Joined: Dec 2002
Posts: 560
Likes: 1
From: Mooresville NC
Like all the others said. It's important to fluctuate the rpms during the 20-30 minute break-in. don't let it sit too long at one rpm. You want to get th lifter to spin in the lifter groove. Keeping at idle or one rpm will, kinda prematurely dig out the lifter face.
