Some Break-in Ifo from Crane

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nm9stheham

nm9stheham

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This is for the FWIW department.... just passing along info. (Disclaimer: I offer no guarantees of this being info that will work for you, so use it at your own risk.)

I have read where Crane Cams has stated you should have no more than 'so many' lbs lifter pressure on the cam lobe at max lift (over-the-nose) for flat tappet cams . So I called to ask what would be the safe level of lifter pressure on the cam for break-in, and the tech guy said to keep it under 250 lbs lifter pressure over-the-nose. I was considering getting some lighter valve springs for break-in, but this no longer looks necessary; our springs will exert 180 lbs of lifter pressure over-the-nose. (If you want to know your lifter pressure, just divide the actual spring pressure by the rocker ratio. Edit to correct: MULTIPLY)

He added that they now recommend just straight break-in oils only, rather than the break-in additives. If I understood what I was told correctly, it has been found in some testing that the additives need to blend into the oil at a certain temperature range and over some time, and this does not always happen. He even recommended the straight break-in oil over their own brand of break-in additive. Break-in oils mentioned were Brad Penn, Joe Gibbs, and... darned if I can remember now! (It was a common one...Edit to add: It was their own brand.)

Again... FWIW. Just passing the info along for anyone to consider who is so inclined. Hope it helps.
 
Sounds about right to me. This is why I never recommend the additive, but rather the oil with the additives already mixed in.
 
Pretty much any single spring with a dampener is fine for break in and yes, additives are not evenly dispersed until it's been run a bit so break in oils are best. You just can't install the inner one if your cam runs a dual spring assembly. I'll add - I use the Crane cam lube specifically because it's a paste & doesn;t run off. You also should verify lifter rotation during assembly, and once the valvetrain is assembled - the fewer rotations the better before you start it so the lube stays put.
 
Might be a dumb question but just visualizing in my head wouldn't the lifter pressure be the spring pressure times the rocker ratio? I'm confused how that works...
 
If you want to know about Crane Cams : call and ask for Chase Knight period....if he has not retired. He will set the record straight. Chase was the Cam expert at Crane.
I have talked to him many times and my partner I work with worked with him at Crane for too many years to count. And...... he knows Mopars.
Jus sayin....
 
I just asked in another post about breaking in my cam with the doubles verses what Lunati said break in with the single. So it sounds like break in should be done with the singles.
 
Ya know.... you made me stop and think.... and I think you are 100% correct. Seems like it WOULD be the rocker ratio times the valve spring pressure. It should work as you say for any simple lever system. Yep, the sum of the moments has to be 0 and the shorter moment arm has to have the higher force. THANKS FOR THE CORRECTION, MOPEkidD-3.

Now I gotta go back and rework my lifter pressure...... looks like it will be well ABOVE 250 lbs over-the-nose. (Out-of-the-box Edelbrock springs on their Performer RPM AL heads.)

This all started because I was gonna just pull the damper out but measured the damper and found that it only reduced the valve spring pressure at full lift from 285 to 270 lbs. I found some lighter springs (Melling 466114) but did not want to 'spring' $80 for just breaking in the new cam. Might just have to do that though.

And Moper, I have paid attention to your comments on lifter rotation at start up and even in build testing. Seems pretty wise.

Looks like most all standard performance valve setups are violating the 300 lbs over-the nose pressure for normal running including the Crane parts, so that number will be struck from my original post, unless I can find better info the back that up. I do know that I broke in a new Crane cam many moons in the past with springs that would have put well above 250 lbs on the lifter, and that cam was good for about 100k miles.......sooo, take that 250 number FWIW....
 
put the additive in the new oil 5 qt jug of oil......dump into engine....additive not mixed...LOL
 
moper said:
Pretty much any single spring with a dampener is fine for break in and yes, additives are not evenly dispersed until it's been run a bit so break in oils are best. You just can't install the inner one if your cam runs a dual spring assembly. I'll add - I use the Crane cam lube specifically because it's a paste & doesn;t run off. You also should verify lifter rotation during assembly, and once the valvetrain is assembled - the fewer rotations the better before you start it so the lube stays put.
Click to expand...
I was worried about the same problem with turning to many times (like adjusting rockers) and ken at oregon cam said cam lube is specifically designed to impregnate the surfaces? Disclosure: I absolutely do not know as much about any of this stuff as moper. This is just put out there for discussion sake - no one arguing.
 
none of the this imformation is new, a good refresher for some and an education for some.
thank you guys.
 
After changing the cam..adjust the rockers with the intake manifold off the engine....I use those acid brushes to make sure the cam stays covered with break in paste.....then engine is set a TDC no. 1 firing...intake installed...drop in distributor...fire engine..

this **** is not rocket science.......
 
70aarcuda said:
put the additive in the new oil 5 qt jug of oil......dump into engine....additive not mixed...LOL
Click to expand...
There is a product called AvBlend used in small aircraft engines used mainly to help valve stem lubrication and prevent valve sticking. It doesn't work to just dump it in the crankcase; it has to be run and brought up to moderate temp to get the ingredients to stay in the oil. Otherwise it will just evaporate off. The point being that ....pouring in at room temp is not always blending. That may be the case with the ZDDP additives; without knowing the supposed tests done, it is hard to say.
 
How good is straight STP as an assembly lube then?
 
Lol no prob 'nm9' just more thinking out loud. I find that lifter pressure number a bit strange though because even the pamphlet released by Crane says 300 lbs. or less seat pressure is fine for break in which translates to 450 lbs at the lifter. And 250 lb lifter pressure is like a stock factory spring.
 
Yes, been thinking the same. I may call the tech guy back and ask again if he really meant LIFTER pressure..... I asked it specifically 2x. Is that pamphlet on their website?
 
The pamphlet I found that specifically mentions spring pressures is from their Australian website oddly enough... The one from their American site only gives a vague reference to "race cams requiring high(??) spring pressures with dual springs"

[ame="http://cranecams.com.au/pdfs/Flat%20Tappet%20Camshaft%20Break-In%20Procedure.pdf"]http://cranecams.com.au/pdfs/Flat%20Tappet%20Camshaft%20Break-In%20Procedure.pdf[/ame]
 
MOPEkidD-3 said:
The pamphlet I found that specifically mentions spring pressures is from their Australian website oddly enough... The one from their American site only gives a vague reference
Click to expand...
I can see the problem in this already. Is it obvious? Australia is upside down damn near when you look at it on a handheld globe so the lifters are actually droppers and thus needing less pressure over the nose! Problem solved.:D
 
RustyRatRod said:
Sounds about right to me. This is why I never recommend the additive, but rather the oil with the additives already mixed in.
Click to expand...

Not to drop a 'lump of coal' in Your Co-Co-Puffs RRR (with consummate respects) :D

Zinc %'s come and go with the bean counter engineering constraints. (yes even the aftermarket)

---I remember to this day a pressure cooker loaded up with 2 pints of Moly bearing lube.---& 16 'lifters' ---
 
If you want to calculate actual OPEN spring pressure, the rocker arm has little to do with it.

To do the math, you need to know several things.

1. Seat pressure at your installed height.
2. Spring rate (given in pounds per inch)
3. ACTUAL lift.

Then do the math.

If you have 100 lbs at 1.700, and an actual lift of .500, with a spring rate of 300 lbs/inch it works out to:

100 plus (spring rate times lift) or using the above numbers .500 times 300, which equals 150.

Now add the 100 (from seat pressure) to the 150 from lift time spring rate and you get 250 over the nose.

The EXACT same spring with .600 lift would be 280 OVER THE NOSE with the same seat pressure.

It's all simple math but you need all the variables to do the math.
 
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