I am not far from breaking in my new 383 and wanted some advise from you guys. Engine has a COMP Roller cam. Questions ?

With a H. roller cam do I still need to break the engine in like it was not a roller. ie 20 minutes 2000 rpms ?

Should I keep the motor below a certain RPM for so many miles ?

What engine oil would you recommend for break in ?

How long before I should switch to synthetic ?

Motor Specs are on my website for review.

Any other tips would be appreciated. Builder gave some good advise but I wanted to hear from you guys with more experience at this than I have.

Thanks in Advance.

:seeya

 

Roller cams do not need to be broken in like flat tappet cam did.
Some will say break it in race and it will be fast but thats is against all sound reasoning. All breaking an engine in consists of is wearing away metal of parts that fit tight. Today that is not the problem that it was years ago. Today parts are made with much more precision but running it real hard can do nothing other than risk gallding the pistons. For the first 500 miles I would not rev it beyond 3000rpm do not run at sustained high speed. Most things that I have read say use dino jucie for 10,000 miles but I switched mine to synthetic at 2500 with no problems. After you get about 100 miles on it accelerate hard with it in high gear after you get up to like 80 then slow and allow time for parts to cool and do it again after a few times this will have sealed the rings. Good luck with your new engine and enjoy it.

 

You will still want to do a cam break-in type of cycle to get the assembly lube out of the motor regardless if you are running a roller or not. My new engine has a LOT of assembly lube in it and I do not plan on running it for long. 10-15 minutes after it is warmed up just to get the oil warm and the assembly lube suspended in it. There are a couple other posts from the past week that deal with break-in procedures and they answer many of you other questions as well.

 

Here is the URL...
http://forums.corvetteforum.com/zerothread?id=199439

 

As already mentioned, roller cams don't require any break in, certainly not the 2000+rpm for 20 minutes thing. I would recommend applying some moly break in lube to the cam and distributor gear though - especially if you're using a bronze distributor gear.

If you used moly rings the engine will break in almost immediately. You should just drive it normally. I would recommend a few 3/4 throttle acceleration runs fo a few hundred yards, and then fully close the throttle. This will help seat the rings faster.

I usually dyno test my motors after building them, starting them for the first time on the dyno. We start the engine and let it fast idle, checking for good oil pressure, unusual sounds and any leaks. If everything appears noraml, we let it reach normal operating temp. Once it's gotten to normal tmep, we shut if off and check the valve lash. With that set we start tuning it at idle, and then at part throttle acceleration. After getting those areas dialed in, we shut it off, and check the plugs and valve lash again. If everything is still good, we start dyno testing and tuning for maximum torque and power, including WOT. Before the day is done, the motor has usually done 20 or WOT throttle dyno pulls, with several to redline.

I would rather find that something was assembled incorrectly or that there is a problem on the dyno rather than a week later when the engine is in the car and I'm driving down the road.

As for what oil to use - I always use a high quality, mineral oil, I like Valvoline VR1 Racing oil the best for this. I would run that for 500 miles, then do a filter and oil change. fun a good mineral oil for another 500 miles and do another filter and oil change. Then with about 1000 miles or so, you can switch to synthetic and follow a normal oil change cycle. The main reason I don't like to run synthetic sooner is that is's kinda a waste of money to only run it for a few hundred miles and then drain it out.

 

yes, go to that thread.. good info there..