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[GMCnet] Comp Cam Break In [message #238653] Mon, 03 February 2014 16:26 Go to previous message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma:
Senior Member
G'day,

I think I understand that for a flat tappet cam you should:

1) coat the cam and lifters with break in lube before you install them
2) set the engine at No. 1 TDC then insert the cam
3) time the cam before you install the lifters
4) install the distributor and set the ignition timing before you install the lifters
5) use single valve springs during the break in process
6) not turn over the engine by hand after the lifters have been installed
7) not use synthetic oil during the break in process
8) use engine break in oil (1400 ppm ZDDP) when breaking in the cam
9) run the engine at 2000 - 2500 rpm (varying the rpm's) for 20-30 minutes to break in the cam

However I never REALLY understood what the cam break in process accomplished. I called Comp Cams tech support and informed them
that I had a Caddy 500 with a Nitrided cam and asked if I needed to use the same procedure as noted above and was advised YES!

I then asked what does the break in process do to the cam and lifters. I was advised that it assures that the lifters are spinning
in their bores establishing the wear pattern on the cam lobes and lifter faces quickly which assures that the lifters will continue
spinning over the life of the engine.

I asked why do you need the 2000 - 2500 rpm; why can't a lower rpm over a longer period accomplish the same thing and was advised
that rpm range creates more force to overcome any resistance between the lifter and lifter bores to make sure the lifters are
spinning.

While poking around the Comp Cams website I stumbled on to this page; LOTS of good info here!

http://www.cpgnation.com/forum/comp-cams-product-tech.html

If I've missed anything or if you wish to comment or criticize PLEASE do so!

Regards,
Rob M.
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426


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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
 
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