cam break in question

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moparker

moparker

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Installed a Lunati cam in my 340. Lunati recommends breaking it in with single valve springs then adding the centers after. I've never heard of doing this way. Also most guys of talked to break them in with the doubles. Any opinions or advice is greatly appreciated.
 
So personally I didnt touch my heads when I broke my cam in. But the book does say single spring. Maybe it matters more if youre using solid tappets?
 
So yours was broke in with the doubles?
 
the person who MAKES the cam tells you how to break it in, why are you asking us ?


not to sound rash, but they have a reason they tell you to only use a singe spring
it doesn't matter what we say, the person who made it is the authority in this case


now, if you want to risk blowing a 200 dollar cam and another 100 dollars in parts because you don't want to go through the trouble of removing a spring, be my guest...but it will be a whole lot more trouble if you wipe a lobe


oh, and don't worry about using break in lube, I know a guy who never uses it ;)
 
diymirage said:
the person who MAKES the cam tells you how to break it in, why are you asking us ?


not to sound rash,
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^^THIS^^ Even if you were an expert engineer (I ain't) and you KNEW that part of the manufacturer's required procedure was unnecessary, you MUST follow the manufacturer's destructions FOR ONE SIMPLE REASON

and that reason is, that any warrantee on the item WILL be void if you admit, or they can prove, that you did not follow their requirements.
 
Most double springs require the inner spring be removed for break in. This is nothing new and it's not a secret. Been that way 50 years.
 
I`m the type that would follow instructions.
I know it will be a PIA to install the inners but how would you feel if it fails?
I`m not taking the chances. To each their own..
 
RustyRatRod said:
Most double springs require the inner spring be removed for break in. This is nothing new and it's not a secret. Been that way 50 years.
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Guess Im too lazy... Always left em in. But... ther's always first time
 
Most cam manufacturers say to remove the inner springs during break-in. Never heard of one that didn't. If the cam maker says to remove them, I would remove them.
 
moparker said:
Any opinions or advice is greatly appreciated.
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moparker said:
Sorry I asked. Have a great day.
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which one is it?


there is nothing wrong with asking, but when you quote the authority on something and then ask advice it kinda defeats the purpose no?

almost like a Christian who has the Holy Spirit living inside of him asking for a guardian angel, you moving down the chain of command, not up :D
 
Higher spring pressure= Less lube, higher temp, more friction at the lobe. Dont need stiff springs for a 2700 rpm romp in the woods.
 
The big question is whats the seat pressure on the springs? Next are they double or single with damper . Never had a problem with 100 to 120 seat pressure no need to remove inners just start it up and immediately run at 2000+ varying rpm for 20-30 min.
 
I'm gonna remove the inners. That's what I gonna do anyway but, thought I would ask people with more experience then me. Didn't expect the "rash" coments. Thanks.
 
Rash? Not a single one was rash. Do you cower under a table when a bird lights on the window sill? My God man, all we did was answer your question.
 
depends on spring load , and better safe than sorry. and here is a tip - when getting heads done at a shop and breaking in a new cam-ask for the heads to be assembled with only the outers
 
Thanks to all the helpful comments. Goin back under my table now.
 
moparker said:
Thanks to all the helpful comments. Goin back under my table now.
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lol Take it easy man, it was all in good fun. I don't think anybody here meant anything the way you took it. Good luck and keep us posted. But you have to come out from under the table for that. lol
 
RustyRatRod said:
lol Take it easy man, it was all in good fun. I don't think anybody here meant anything the way you took it. Good luck and keep us posted. But you have to come out from under the table for that. lol
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Unless he's got a laptop under there.

Some of the fellas on this board may come across.... hard. But I think that's just typical of our type of guys. We're that old school, give **** and take **** type. The same ones that still bug our buddies about something stupid they did 20 years ago. That drink beers and give each other the gears while working on **** together. Can't take it all personal.
 
I've run as much as 180 on the seat with SFT cams and NEVER EVER have I removed the inner. If you can start an engine and make it run then you can do it without pulling the inner or using low ratio rockers.

What kills the cams on start up is cranking on the starter and not making it run.

The single biggest pile of crap for cam oiling is the big block Chevy. I've done dozens of them with SFT and I didn't pull any inner son those.

If you are not confident in your ability to get an engine up and running then pull the infers. I just don't want to do the work.
 
I kinda decided that the single spring thing has to do with the seat pressure on the springs; if it will stay under 300# on the seat when wide open, then I am not inclined to do anything special. We recently broke in my son's 340 with a new Crane cam, where the seat pressures reached almost 300 # open, and we did it with both springs in place. No problems. And I have done plenty of cams with dual springs in place, all in that range of open spring pressure, with perfect results and loooong cam life. (longer than the pistons and rings!)

One thing I recall on the manufacturer's instructions is that they make not distinction on cams or spring pressures. So I tend to think that they are making a wide statement that covers all their cams and all spring pressures. And, you never saw these instructions 'back in the day', at least that I can recall.

Disclaimer: Follow my method and philosophy at your own risk ......
 
If you all are talking about the damper springs " the Flat springs" on the inside of the main spring they can stay in place.

Most look to have two springs but the are dampers. They can be left in place as stated .

It is if you have outer spring and inner spring Both round coils is when you need to remove the inner. Not if you have performance springs with only surge dampers. as most performance springs.
 
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