cam break in

[grumpyvette]

Proper cam break in is really all about getting enough constant oil flow between the lifters and lobe surfaces, The cam and lifters should be coated with moly cam lube before being installed and a can of G.M. E.O.S or MOLY ADDITIVE added to the oil, Break-in sould be done by running the engine in the 2000+to 4000rpm range for about 20 min MINIMUM to get the oil to the cam and keep it there, in significant volume. This can be difficult, because you need to set the timming, etc. and keep the engine cool. Dry cranking the engine hurts it because it can wipe off the cam lube. YOU NEED THE MOLY LUBE AND ADDITIVES,YOU NEED TO KEEP THE RPMS ABOVE about 2000rpm

for a flat tappet cam to break in correctly you must keep the rpms high enought that both the spinning crank assembly is throwinhg a constant oil spray and the lifters are constantly supported on a film of oil spraying from the area around the lifter bores, plus the cam lobes contact must not drag across the lifter base for a long enought time to squeeze out that oil film between them, untill the lifter base wears to exactly mate with the cam lobe. the contact time and oil volume flowing across the contact area are both dependent on the engines rpm range. it takes a minimum of about 1500rpm before your getting into the safe oil volume and time area with new parts

 

read this

http://www.cranecams.com/?show=camLiftWear

 

http://www.cranecams.com/?show=adjustingValveTrain

 

http://www.mrmoly.com/break-in.html

 

http://www.holley.com/HiOctn/TechServ/TechInfo/IECCTech1.html

 

http://www.holley.com/HiOctn/TechServ/TechInfo/IECCTech2.html

http://www.holley.com/HiOctn/TechServ/TechInfo/IECCTech3.html

http://www.holley.com/HiOctn/TechServ/TechInfo/IECCTech4.html

http://www.holley.com/HiOctn/TechServ/TechInfo/IECCTech5.html

 

http://www.engineparts.com/Motorhead/techstuff/caminstall.html

 

http://www.2quicknovas.com/happycams.html

 

http://www.iskycams.com/techinfo_index.html

 

you should use mineral base oil as its cheaper,it allows the parts to mate faster and your going to throw it out in less than 3 hours with the partly clogged filter after cam break-in, you need to change the oil filter and additives to remove them and any metallic dust from the engine break-in to prevent that crud from clogging the filter, after that its your choice as to the oil used ,but I normally use mobile 1 synthetic and add a pint of marvel mystery oil for added corrosion protection

 

AND YES THE FILTER YOU USE MATTERS

READ THIS

 

http://www.scuderiaciriani.com/rx7/oil_filter_study/

[Michael]

Grumpy,

 

Could you include a few words on how the break-in procedure differs for roller cams, especially mechanical rollers? By the way, for moderately aggressive lobes (say, 0.630" lift in a big block, 240 @ 0.050" duration) in engines that are serviced often but rarely street-driven (a few hundred miles per year, maybe 1000 miles/year max), what is the basis of the often-claimed advantage of hydraulic roller over mechanical roller?