Camshaft break-in

I m going to have a pair of HKS 264 In/Ex cams fitted to my T61 supra. What lubricant should I use for the installations and break-in process of the cams???

CHeers

adi

Hi Adi, just your normal oil in the engine, but when you fit the cams, the normal procedure for other cams i have used, (don't know about HKS) but i can't see it being any different, is to coat the friction surfaces in cam lube, which is a special and very viscus oil designed for start up and break in of cams.

Then start the engine and hold at about 2-3,000 RPM for around 15-20 minutes, i know it sounds harsh, but in reality the cam friction surfaces are much less loaded at this RPM than at idle speeds.

Hi Adi, just your normal oil in the engine, but when you fit the cams, the normal procedure for other cams i have used, (don't know about HKS) but i can't see it being any different, is to coat the friction surfaces in cam lube, which is a special and very viscus oil designed for start up and break in of cams.

Then start the engine and hold at about 2-3,000 RPM for around 15-20 minutes, i know it sounds harsh, but in reality the cam friction surfaces are much less loaded at this RPM than at idle speeds.

Hi Dick! thanks! What is this special cam lube and where can I get it from???

Now the thing is that I m getting a brand new shortblock, head and valvetrain installed in my car so should I follow the same start up procedure as you mentioned.

The cam lube should be available from most aftermarket/tuning parts factors, don't know how thin on the ground they are in your location? failing that, an on line shop i guess.

As for using the same procedure with a fully rebuilt engine, TBH I'm not quite sure, can't see holding 2K RPM for a while being a problem, unless the temps get to high, might be an idea to email Chris Wilson for an experts opinion;)

Is this build going to be for strip & street?

Its just for street. Everything is stock (blueprinted shortblock), I m just refurbishing my car so I dont have to worry about it for quite some time to come. I m going in for a new engine, gearbox, diff, suspension, brakes and radiator. I ve not managed to get the car running well with the EMU so decided to get a professional install the Autronic SM4 standalone!!!

How is your car doing mate? the T67 must be insanely fast!

The whole hold it at 2000rpm thing was for old school pushrod engines. It's not needed for modern overhead cams. Just fit them and don't worry about it. Normal engine oil would be fine, or assembly lube if it's going to be a while before you start it after fitting.

The whole hold it at 2000rpm thing was for old school pushrod engines. It's not needed for modern overhead cams. Just fit them and don't worry about it. Normal engine oil would be fine, or assembly lube if it's going to be a while before you start it after fitting.

I think Kent Cams, Piper and other manufactures would disagree,

its not for just push rod engines,these suffer the same sort of loading as OHC, i suspect a lot of Japanese cam manufactures don't bother with break in/initial work hardening process, but it does make a big difference to the cams lifespan.

The loading on a camshaft, whether OHC or push rod is one of if not the highest of all the engine parts!

Can you imagine what leaving a new cam on idle for any period, that has no thermal or work hardening/break in will do.

Its just for street. Everything is stock (blueprinted shortblock), I m just refurbishing my car so I dont have to worry about it for quite some time to come. I m going in for a new engine, gearbox, diff, suspension, brakes and radiator. I ve not managed to get the car running well with the EMU so decided to get a professional install the Autronic SM4 standalone!!!

 

How is your car doing mate? the T67 must be insanely fast!

My Supra if pretty good thanks, its a GT4088 though:) and i think its quick, i soon get used to upgrades.

The whole hold it at 2000rpm thing was for old school pushrod engines. It's not needed for modern overhead cams. Just fit them and don't worry about it. Normal engine oil would be fine, or assembly lube if it's going to be a while before you start it after fitting.

I would agree, on any profile cam and spring combination you'll run in a road direct acting OHC engine the loadings are insignificant. Just fire it up and drive as normal. Pushrod V8's with huge valves, huge lifts and high RPM limits, or things like my Atlantic 4A-GE race engine with near 11,000 RPM limit and a LOT of lift are different matters, as the valve sping loadings, and thus cam follower to cam loadings are huge.

I would agree, on any profile cam and spring combination you'll run in a road direct acting OHC engine the loadings are insignificant. Just fire it up and drive as normal. Pushrod V8's with huge valves, huge lifts and high RPM limits, or things like my Atlantic 4A-GE race engine with near 11,000 RPM limit and a LOT of lift are different matters, as the valve sping loadings, and thus cam follower to cam loadings are huge.

If this is the case why did Kent cams advise this procedure when a bought a higher lift cam for a VW OHC engine? i collected the cam in person and spoke directly to one of their designers/engineers.

So you disagree that the valve train on any engine is one of the most highly stressed components?

The whole hold it at 2000rpm thing was for old school pushrod engines. It's not needed for modern overhead cams. Just fit them and don't worry about it. Normal engine oil would be fine, or assembly lube if it's going to be a while before you start it after fitting.

Hmmm, I think old school methods are done these days purely as a CYA thing. Can understand that materials and coatings are different these days and might not be required. I still do it on the old A series engines

Mind you, it is like the bike engine running in procedure of going flat out

Ok so with the mixed views on the camshaft break-in. Should I use a molybdenum lube on the cam lobes for the initial start-up of the engine or will engine oil do???