breaking in new cams and top end

[rtrocket59]

I plan on rebuilding my top end when I do my turbo build. I was going to get HKS272 cams, HKS cam gears, Crower springs/ valves, weisco 8:1 pistons, and eagle rods. I have read so many contradictory opinions on breaking in motors that im confused now! haha but I heard when breaking in cams to keep the rpms low and when breaking in top ends, to vary rpms (up to 6000). Should I have them installed at different times or is there another method to use?

 

[dino4g63]

I say break it in all together. I just completed an 2.3 stroker build with 272 cams. I used crane cams break in oil. I took it easy on the first run. Varying RPM, engine braking, and taking it easy for about 20 minutes. I changed oil and checked coolant. The oil will look nasty from assembly lube coming out. I took the car back out for run 2. I used light to medium throttle with engine braking for about 15 minutes. Checked oil and coolant again. 3rd run I varyed throttle giving it medium to heavy loads with engine breaking. After the 3rd run with heavy loads. Change oil, check coolant, retorque head studs. After that I changed oil every 1000 miles to 5000 miles. Do not use syn oil till after 5000 miles at least. You may want to hold off even longer.

 

[Heartless]

If you've ready the forums and it sounds like you have you will have to realize this thread will be the same as the rest. Everyone has their own way of breaking it in. Some will baby it, others run it like they stole it. From research I've done, you only have the first 20miles to seat your rings. I get the car running and set the timing as she warms up. Make sure no leaks are found (if they are shut off, fix, and start again). And let her heat cycle (fans kick on) while varying the rpm's between 1500-3500, check every now and again to make sure she'll idle ok. Once shes warmed up, shut her down, leave, and let it cool complety down (depending on your headgasket, some require a retorque after completely cooling down, others don't). Once she cooled all the way down you an make a small trip. I usually do 10 pulls in 3rd (50% - 80% throttle during different pulls) don't get the rpms too high just yet. But make pulls between 25mph and 45mph and let off while in gear and coast down to 25mph and let the engine vacuum try to help seat the rings. Return home, let the engine cool off. Change the oil and filter and then again at 300miles, 600 miles, 1000 miles, and then at 3000 miles start regular intervals. Remember to use regular oil and not synthetic til at least 3000 miles if you wish to do so. This is how I personally have done every engine I've put together 4g63, SBC, SBF, BBC, BBF, BBC, ect. Again different people will tell you different things.

 

[dino4g63]

I think I may have been more aggressive than Heartless, but I think his method is also effective. Remember vary RPM, check fluids, and complete cool downs. Thanks Heartless, I forgot to mention the cool down part.

 

[Heartless]

No problem Dino's method will work just fine as well. Its all about the initial fire up and getting those rings to seat within the small window. And just remember there may be problems along the way, don't get discouraged, it will be well worth it in the end!
Also on a side note some people say to stay away from the BC springs, someone had them break (granted they were running Kelford 272's which have more lift than the usual 272). I'm running them without issue but they are properly setup as well and I'm only reving to 8k (not much reason to go past there as most builds peak by then if not before).

 

[Colt4G63 also]

The lifters are roller style, not flat tappet, so you really don't have to worry about breaking the cams in.

Break in your rings in whichever way you decide is best, and as long as the valvetrain is assembled and prelubed properly, you don't have to give it a second thought.

 

[xyexz]

I did Heartless' way and couldn't be happier, great compression across the board and strong.

Now if I could just get stupid small oil leaks stopped I'll be all good.

 

[Heartless]

Lol! Xyexz I'm sure theres a sealant or crush-washer for that

 

[rtrocket59]

thanks for the feedback guys!