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Is there a break in period for the Camshafts when I install them? I just got done installing them and drove around a bit. Plan on changing the oil later tomorrow since I was due anyways. There will probably be around 30 miles on them by then. Anything I should do differently this change? Any additives or anything?


Most importantly, when can I gun it.:funny:
 

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To properly break in a new cam you should make sure that the motor is 100% ready to fire and run. Once you start it bring the rpms up to about 2200 rpms for a few minutes, after that drop down to about 1500 rpms for a few minutes then back up to 2200 rpms. Do this for about 15-20 minutes. After the run period let the engien cool completely, change the oil and then give er hell. This is the only way to properly break a cam in, if you have already started it...you have...and then just let it idle and drive around a bit then it is too late for a proper break in. You may or may not have issues, most cams that aren't properly broken in that fail do so fairly quick, babying them doesn't do anything. So just go out run it like you want to.
 

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To properly break in a new cam you should make sure that the motor is 100% ready to fire and run. Once you start it bring the rpms up to about 2200 rpms for a few minutes, after that drop down to about 1500 rpms for a few minutes then back up to 2200 rpms. Do this for about 15-20 minutes. After the run period let the engien cool completely, change the oil and then give er hell. This is the only way to properly break a cam in, if you have already started it...you have...and then just let it idle and drive around a bit then it is too late for a proper break in. You may or may not have issues, most cams that aren't properly broken in that fail do so fairly quick, babying them doesn't do anything. So just go out run it like you want to.
well said, you beat me too it. this is how i did mine when i put the HO's in and no problems so far.
 

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that's the old school way to break in flat tappet cams. today's modern roller cams have almost no break in period, because they don't "marry" themselves together (the lifters to the lobes) like on a flat tappet. so on the 5.2s and 5.9s you can do a cam swap, fire it up, and go! no need to do the 20 minutes at 2500 rpm thing.

on the 4.7, I don't know though. with the overhead cam design on those motors, is there any kind of a "roller lifter" or does the cam lobe push directly on the valve stem? if it's simply a lifter pushing on a valve stem, then yea, I'd probably wanna do the old school break in, but I don't think that's how these are set up...cause there'd be no adjustment for valve lash that way, so there's got to be some type of lifter, rocker combination.
 

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that's the old school way to break in flat tappet cams. today's modern roller cams have almost no break in period, because they don't "marry" themselves together (the lifters to the lobes) like on a flat tappet. so on the 5.2s and 5.9s you can do a cam swap, fire it up, and go! no need to do the 20 minutes at 2500 rpm thing.

on the 4.7, I don't know though. with the overhead cam design on those motors, is there any kind of a "roller lifter" or does the cam lobe push directly on the valve stem? if it's simply a lifter pushing on a valve stem, then yea, I'd probably wanna do the old school break in, but I don't think that's how these are set up...cause there'd be no adjustment for valve lash that way, so there's got to be some type of lifter, rocker combination.

on the 4.7's there are no push rods...... you have a lifter "lash adjuster" that sits on one side the cam in the center then the valve stem on the other side.... the roller rocker sits on-top of the "lash adjuster" runs under the cam then presses on the valve stem when the lobe comes around. the only pivot point is what little bit you get ontop of the lash adjuster and the roller on the rocker when the cam comes around...


i as well would like to know the proper brake in on these motors as im putting in H.O. cams here in the next few weekends :huh:
 

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It's all rollers...nothing needs 'broken in' or 'married'. There better be no wear seeing as how the cam rides in aluminum...there are no bearings in the head or cap.

I'd give it a couple heat cycles, then go play.
 

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It's all rollers...nothing needs 'broken in' or 'married'. There better be no wear seeing as how the cam rides in aluminum...there are no bearings in the head or cap.

I'd give it a couple heat cycles, then go play.


it's not the bearings that need broke in on a motor--rings and cams is it.

the piston rings need to cut down the hone on the cylinder walls and marry themsleves to the cylinder walls for good sealing, and the cams for the reasons above--flat tappets marrying themselves to the lobes.

I know that a 4.7 has no pushrods, it's an OHC motor! on that rocker with lash caps though that you mentioned...do those have a needle bearing on them? or is it just a flat/rounded point contacting the cam lobe? if it's got a needle bearing, then I'd say it's no different than a roller cam...fire it up and go.
 

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it's not the bearings that need broke in on a motor--rings and cams is it.

the piston rings need to cut down the hone on the cylinder walls and marry themsleves to the cylinder walls for good sealing, and the cams for the reasons above--flat tappets marrying themselves to the lobes.

I know that a 4.7 has no pushrods, it's an OHC motor! on that rocker with lash caps though that you mentioned...do those have a needle bearing on them? or is it just a flat/rounded point contacting the cam lobe? if it's got a needle bearing, then I'd say it's no different than a roller cam...fire it up and go.
I know about breaking in cylinders/rings and flat tappet cams, but this is purely 4.7 cam related so that's what I was talking about.

The 4.7's cam followers have a bearing that runs on the cam. So, like we both said, fire it up and go.

I think maybe you meant to quote 'wah'
 

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Roller cams are alot more foregiving than non roller cams when it comes to break in but the same procedures should be applied like I stated above. If you follow that procedure, no matter what type of cam you have, you stand the best chance of not having a cam failure due to a flat lobe.....and yes it does happen on roller cams also.

Another huge thing to keep in mind during cam break in...make sure that you use oil additive. All gasoline engine oils made for street use do not have the additive that is required for good cam break in(I forget what it is...zinc or something)you can get the additive from any of the name brand cam mfgs. Some of the diesel oils used to be ok to use but they have been changing their additives also to comply with the EPA.
 

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Well, I've had my HO cams in for nearly 5 years and a good 60k miles...no issues.

I started it, let it idle a few minutes to check for leaks then drove it somewhat gently to warm. Parked it and repeated the next day. Third day, drove it to my liking.
 

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Discussion Starter #13
Well thanks for the info guys but like was said before what is done is done at this point nothing I can really do about it. Just hope for the best and enjoy my cams. Just changed my oil today and I'm hopefully gonna be enjoying the hell out of these cams in the next few days, lol.
 

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Another huge thing to keep in mind during cam break in...make sure that you use oil additive. All gasoline engine oils made for street use do not have the additive that is required for good cam break in(I forget what it is...zinc or something)you can get the additive from any of the name brand cam mfgs. Some of the diesel oils used to be ok to use but they have been changing their additives also to comply with the EPA.

do you really need the additive, or just use a good amount of moly assembly lube on the lobes during install? that's all i did.
 

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do you really need the additive, or just use a good amount of moly assembly lube on the lobes during install? that's all i did.
The additive (ZDDP) is a good thing to use in your oil all the time with a flat tappet cam, especially if you run alot of spring pressure.

We don't need it in the 4.7, ever.
 

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Discussion Starter #16
Ok so I at least used assembly lube, lol.



And I like the cams.:D
 
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