Hey guys, I rebuilt my 305 and my 700r and put them back in the car. One of the new parts was the cam, an edelbrock 2102. The instructions say that I need to "break in" the cam by letting it rev at 2000 rpms for 20 min as soon as I start it. I started it the other night but needed to set the timing, hook up a manual oil pressure guage, and check the cooling system. I did not run the engine for more than 3-5 min. at a time. Should I still do the break in routine? I noticed alot of vibration coming from the crank area. The crank was not new but was turned .10 by a local speed shop. Will this go away or should I start pulling the engine out now? Thanks for being here for guys like me.

 

rgtrough,

When you restart, finish the cam break-in proceedure. After the required time to polish the lobes and lifters, let it idle down, and then diagnose the "vibration". As long as you have oil pressure and nothing is falling apart, you should try to polish the cam as best you can by maintaining RPMs. Remember that 2,000 RPM at the crank is only 1,000 RPM at the cam, and that isn't a lot of speed for polishing a rough cast lobe with a flat metal disc (lifter).

Don't be surprised if the engine gets very hot during the break-in. It happens to me every time. Just keep a close eye on the oil pressure and listen for any unusual noises. Placing an electric fan in front of the radiator can help, but I have "cheated" by running a garden hose with cold (55°F) tap water into the radiator and allowing the heater return hose to drain onto the pavement while breaking in. The garden hose maintains water level so the pump doesn't run dry, and the water/head/case/oil temperature doesn't get out of control. It also flushes all the loose items from the cooling system after the build, so a fresh fill of antifreeze mix can be added right away after break-in.

After several of these, you'll really appreciate roller cams even more - no break-in, and the potential for a lot more ramp.

Good luck. Let us know how it goes.

 

Hey Vader, thanks for the reply. I restarted tonight and took your advice about polishing the cam. Guess what? The bad vibes went away. I have a slight of vibration at idle but I figure that is due to the cam and I still have to tune the carb and set the final timing.
:hail: The guys at this forum are fantastic!!! With you guys' knowledge and experience, I have pulled and rebuilt an engine and trans, taken off all of the emissions, and eliminated the computer, without ever having done this before. Not once did anyone make me feel stupid or less than, when I asked a question. In fact you all encouraged me to ask them. If there is some way you can post this in the other threads please do. I have said this many times before "THANKS FOR BEING HERE FOR GUYS LIKE ME."

 

I'm not sure what the 2102 cam is specified at, but any cam profile that provides more than 200° of overlap (@ 0.050") will generally cause a little lope at idle. It's just part of the game. Glad it worked out for you. Remember to change the break-in oil soon, so that moly used to break in the cam doesn't get lodged in places that you don't want it.