mother$hip89

I want to make sure I have everything straight for breaking in an engine. I use break in oil, prime the oil system, and run the car for 20 minutes at 2000-3000 rpm, varying the speed. I then drive 30-50 miles doing vacuum pulls. The oil is then changed. I then go until I hit 500 miles. The oil is changed again and the car is driven normally until 1500 miles when the oil is changed again. Does this sound correct? Also, can I start using regular oil at 50 miles or do I still need break in oil until 500 miles? Thanks.

joe_padavano

I hold the RPMs constant at 2200-2500 RPMs for the first 20 minutes. Other than that, your process matches mine. I only use break in oil for the first 20 minute cam break in period.

442Harv

Couple other things I do is, I use just water, no anti freeze, so if I have a problem or leak, I don't have anti freeze all over and waste it. I also have a large box fan, in case the engine runs hot, also fire extinguisher, also I like some one to help me so they can watch the gauges, and the I can also check, and change the timing if needed.

mother$hip89

What's a good initial timing for a 350? I was gonna go 15* advance

oldcutlass

It depends on what distributor your using

mother$hip89

Oh right, it's HEI.

oldcutlass

15/16* will work fine for break in.

cutlassefi

Si agree except for one thing, leave the break in oil in for more than 20min. The zinc in the oil also helps break in the rings consequently potentially improving ring seal as well. Driven recommends 400 miles before a change.