I have read about removing the inner spring on valve springs for the 20 min. cam break-in period. Is this what should always be done or is it just a preference by a few ? These posts about wiping cams have me nervous about cranking up my 454. :confused: My intent is to install a Lunati 288/296 adv.dur., .550/.575 lift and 110 deg LS or a Comp Cams XE284H 284/296 adv. dur., 574/578 lift and 110 deg LS. Which cam should I get and what should be my break-in procedure ? I will be running my 454 75% street/ 25% strip, 500+ hp, "781" heads with 2.19/1.88 valves, performer RPM, Edelbrock 800CFM carb, M-21 and 3.73 gear and headers.
I know we have been here before, but I have narrowed it down to these 2 cams and need help with the final decision. The Lunati described above was recommended by Harold for my setup.
Thanks for all advice ;)

Well whatever cam you get, remove the inner springs for the break in. I did it and put my inner springs in and reset my valves in i think around 2 hours taking my time. Its not a big proceedure if you have the air compressor, air hose attachment and the "bar style" valve spring compressor.

Go to goodwrench.com, click on Performance Parts, get a copy of the engine break-in proceedure.

It's not the cam that will wipe out the cam, it's the springs. If you are concerned, you may want to break the cam in on light valve springs. But, you'll probably be OK if you follow the GM published proceedure. If you're real nervous, break the cam in on light (used?) valve springs. That's how I do race engines with big cams and springs.

Gary

Taking the inner valve springs out is good practice. However I didn't do that whenever I broke in my Comp 294S cam and all is well. It's especially important to remove the inner springs with cams using valve springs with a lot of spring pressure. The idea is to lessen the chances of a lobe failure.

As for the actual cam break-in it's pretty simple. I usually tach the motor up to 2000RPMs (and not let the RPMs fall below that). I'll then vary the RPMs from 2000-3000RPMs for about 20-30 minutes.

Good luck.

Just follow the directions. Exactly.

I'd go with the Lunati 288/296 for your combo and you won't be needing to remove inner springs for break in either.Use Crane spring/retainer kit part # CRN-13308-1 with that cam.

While I realize there are folks on here who have broken in cams without light springs or breakin rockers my choice would be to go with the majority of recommendations on this board as well as almost any cam designer or manufacturer out there & use light springs, or use breakin rockers or at the least remove the inner springs on any flat tappet performance cam.
I have been doing this stuff a long time & I would never run in a performance cam with out doing this.
My preference is to use breakin rockers if available as it is a bit eaiser & I am kinda lazy :D
But, they are kinda pricy unless you do this for a living.

BTW, 460 ford springs make an excellent cheap breakin spring for a Rat ;)
Don't remember the number but I'll find it if anyone wants it.

How many miles or hours are recommended to be run on light springs (inners removed in this case)before adding the inners?

The cam should be well broken in within a half hour or so with the engine rpm varied between 2000-3000 rpm.
It's probably pretty well broken in in the first 10 or 15 minutes but I feel 30 minutes is a safe number. You can do it in your driveway while you are making sure everything is dry & happy.
You could drive the car a short distance & accomplish the same thing but it doesn't afford you the same chance to keep track of everything else you should be watching with a new engine & unless you live next to a freeway it is kinda hard to keep the rpm up without people lookin at you a little funny. :eek:
Of course the ultimate way is an engine dyno or run in stand but not everyone has one in their backyard :D

That's a good idea for Proform. Cheap break-in rockers!

Mike, how much do they cost for the real macoy?

John

Crower gets about $300 a set.
Comp has them a little cheaper but they only have them for small blocks I believe.