Any chance of breaking in new cam with out changing springs.Very hard in my FED to without removing engine.Useing cam with over .570 gross valve lift.Solid flat tappet oils like gibbs will be installed.

I'm confused, you have to pull the engine to get the valve covers off in a front engine dragster.? Anyway I have broken in several flat tappet cams without changing springs. All of my cams were in the .570 lift range. I know it's recommended to use light springs but I never had a problem wearing out cams or lifters.

Rent a set of low ratio break-in rockers from Straub Technologies.... a lot easier than pulling springs to remove and replace inners.

IMO, unacceptable risk to try to break-in flat tappets with full spring rate on them. It's only got to hurt one to ruin the whole deal.

assuming you installed the cam correctly and that is installed with black moly paste on the cam lobes, lifters, pushrod ends and rocker arm pushrod cups and you poured a bottle of GM EOS over the cam lobes, then before you start the engine...

1. make sure it is primed correctly and that oil is dripping from every rocker.

2. Make sure the timing is set correctly so that it fires immediately.

3. once started, hold at least 2500 RPM for 5 minutes then vary the rpm for another 5 minutes and do not overheat.

Take the inner spring out of the springs on the engine, that's your lighter spring, outer spring only for cam break in. No need to pull the engine.

There's no reason to risk the cam going flat any other way.

Move the idle rpm around between 1600- 2000rpm for 20 - 30 minutes.

That has to be tuff operation a race car in which you have to pull the engine to take the valve covers off. I’d spend some bucks to remedy that first.

I personally know 3 people that have wiped out flat tappet cams in the last year alone and all are mechanically savvy not idiots.
I'm putting together a 454 for my street car and was planning on running a Comp cams 280 hydraulic and I'm seriously thinking of going roller, I just don't have time for problems ..............

I can get valve covers off.Spark plug #7 and #8 are down at tubing,have to lift motor about 1 inch to remove plug! Pain in the butt.That just the way it is.Last cam 7 years ago break in with springs installed and all went well.Just worred about new cam.

take it to a dyno and break it in there

Joe

I see you're in Maryland, not sure how far in you are but I'm central NJ and have a run stand if you want to borrow it. Currently being used but should be free in a week or so ...........

Low rocker ratio, like 1.2 is the easiest way to do it, period. Following normal flat tappet cam break in procedures work for typical flat tappet cams but once you move away from these lobes and the valve spring pressure go up due to the lobe design, either use break in springs, remove the inner spring, or low ratio rockers or roll the dice.

Pick your poison.

quote:

Originally posted by HS professor:
I personally know 3 people that have wiped out flat tappet cams in the last year alone and all are mechanically savvy not idiots.
I'm putting together a 454 for my street car and was planning on running a Comp cams 280 hydraulic and I'm seriously thinking of going roller, I just don't have time for problems ..............

Great idea! I finished an EFI 432bbc for a friend. Makes 550 easily with a Comp retro roller cam hydraulic. Very impressed. He has 8k miles already no issues. Bracket races it, street too!