Breaking in a motor

[gjohnson]

I have always had my engines broke in and run on a dyno. This year I am taking a do it yourself approach to refreshing my motor. How do you go about breaking it in? I live in a rural area so I can start it up without ticking off anybody but I figure running it in the garage and driveway won't do much to seat the rings. How long do I need to run it and what rpm do I need to see? Roller cam so I'm not worried about the cam going flat. Thanks.

[Mosidebite]

Always used a non detergent cheaper oil. Primed up good before starting. Up to 2500 rpm on the carb screw, get timing close. Cover radiator to get temp up to normal operating temps as quickly as possible, can start without water and let it run for a minute to get some quick heat in it and then Add water if you choose. Let run for 30 minutes or so, keep temps up. Crack throttle every 2-3 minutes.
That's how I have been instructed to do it and has worked for me for years.
Drain oil, check filter then replace with quality oil then Run it like you stole her.

[Lizardracing]

I like to idle it around 1500 to get the temps up and timing set. Then I check the valve lash and change the oil and filter.
Then I take it too the track and whatever happens is going to happen regardless. I've never seen or heard of any evidence that doing or not doing something had any effect baring FT cam procedures. After the first night I do a leak down to get a baseline for future use.

[Brian Gray]

I'll give you my process. This is key to nuetral wear.

1 oil. Should be conventional with moderate hddp I don't recommend an adative if the oil has a hddp increase

Old school vr1. Will do the job and its cheap.

30 min at idle 2000 rpm . with 15 to 20 deg of timing. Temp stay below 180 deg.

Shut down 30 min cool down. Change oil.

Repeat . 30 min at 2000. 30 min off change to the oil your going to race. Run 30 more min.

Run your hot lap session or first practice about 10 laps under 5000 rpm . change oil. Go race.

I know it sounds like over kill but it works for me.

Remember the money you spent on that engine if you can do anything To make it last a little longer wouldn't it be worth it?

Some builders say break it in how your gonna race it. I don't believe that at all.

Control of the initial wear is key to long lasting performance.

[dereksehi]

I usually break them in with non-detergent sae 30 you can purchase this at any napa store, along with a zinc additive made by engine pro and use a good filter like a napa gold or wix dont use a racing filter as a good filter will catch most of the debris from the break in process and prevent it from going through your bearings. I usually run the for 20-30 minutes between 1500-2500 rpm varying it slightly every couple of minutes to get oil to splash in different locations. After the initial break in I will change the valve springs or put the inner springs back in and change the oil to VR1 conventional racing oil and change the filter. Then run it for another 10 mins at 1500-2500 rpm after this final process I let the engine completely cool down and check the valve lash. The engine is now ready to race after practice or the first night of racing change the oil and go to synthetic if thats what you choose to run.

[Lizardracing]

With FT cams I'd follow the cam recommendations so they are more likely to support you if it went badly but with roller cams the issue isn't the cam it's the rings. Rings need a load to seat properly and the dyno is awesome for this because you can set the brake and RPM or vary the load and RPM as desired. Idling in the driveway isn't doing much but making noise and wasting fuel. The track is probably a distant second to being able to load the engine. As far as helping the engine last longer I agree. The problem is there isn't any quantifiable evidence to support the claim because it's very very hard to take all the variables and make sense of everything in such a way to make constants for results.