A question for PROFESSIONAL engine builders

[rustbucket79]

Oh, I was quite surprised how quickly some of you start making pulls. Am I in the minority of Dyno operators that don’t start pulling a fresh engine right away?

[David Redszus]

I can't locate the GM Motorsports Tech Bulletin; it's been many years ago. Here is what I do remember.

The break-in procedure consists of several stages with increasing speed, load and temperature with a
cool down period between each stage.

Stage one is to let it idle for 15 minutes, shut it off and let it cool for 30 minutes.

Stage two is to run at 25% load and 25% speed for 20 minutes. Let it cool for 45 minutes.

Stage three is to run at 50% load and 50% speed for 20 minutes. Let it cool down for 45 minutes.

Stage four is to run at 75% load and 75% speed for 20 minutes. Let it cool down for 45 minutes.

And finally, run at 100% load and 100% speed for as long as you dare. GM has more guts than I do
and a lot more money as well. Porsche and Mercedes will often run the engine at full load for a few
hours, then take it apart and examine each moving part for clearance and wear.

Never use synthetic motor oil for break-in. It's not the base oil that matters; it's the anti-wear
additive package. A premium oil contains a better anti-wear package which prevents break-in.
Break-in is, after all, merely controlled wear.

In addition to metal surfaces in contact and wearing to fit, thermal expansion and contraction is
important for a properly broken-in engine.

[Warp Speed]

I can't locate the GM Motorsports Tech Bulletin; it's been many years ago. Here is what I do remember.

The break-in procedure consists of several stages with increasing speed, load and temperature with a
cool down period between each stage.

Stage one is to let it idle for 15 minutes, shut it off and let it cool for 30 minutes.

Stage two is to run at 25% load and 25% speed for 20 minutes. Let it cool for 45 minutes.

Stage three is to run at 50% load and 50% speed for 20 minutes. Let it cool down for 45 minutes.

Stage four is to run at 75% load and 75% speed for 20 minutes. Let it cool down for 45 minutes.

And finally, run at 100% load and 100% speed for as long as you dare. GM has more guts than I do
and a lot more money as well. Porsche and Mercedes will often run the engine at full load for a few
hours, then take it apart and examine each moving part for clearance and wear.

Never use synthetic motor oil for break-in. It's not the base oil that matters; it's the anti-wear
additive package. A premium oil contains a better anti-wear package which prevents break-in.
Break-in is, after all, merely controlled wear.

In addition to metal surfaces in contact and wearing to fit, thermal expansion and contraction is
important for a properly broken-in engine.

I break about every rule stated in that procedure! LOL
If we had to follow that, we would never get anything done! Hahaha

I start the engine, check for oil pressure and water flow. Go in and check base timing, then raise the rpm (to 3-4k depending on engine) with 75-100lbft of load until temps come up to minimum for the combo. Start making pulls to 500-1000 from max revs until temps are at desired, the last one being a full pull. Adjust the valves, change the filter and flog it!

[Truckedup]

I can't locate the GM Motorsports Tech Bulletin; it's been many years ago. Here is what I do remember.

The break-in procedure consists of several stages with increasing speed, load and temperature with a
cool down period between each stage.

Stage one is to let it idle for 15 minutes, shut it off and let it cool for 30 minutes.

Stage two is to run at 25% load and 25% speed for 20 minutes. Let it cool for 45 minutes.

Stage three is to run at 50% load and 50% speed for 20 minutes. Let it cool down for 45 minutes.

Stage four is to run at 75% load and 75% speed for 20 minutes. Let it cool down for 45 minutes.

And finally, run at 100% load and 100% speed for as long as you dare. GM has more guts than I do
and a lot more money as well. Porsche and Mercedes will often run the engine at full load for a few
hours, then take it apart and examine each moving part for clearance and wear.

Never use synthetic motor oil for break-in. It's not the base oil that matters; it's the anti-wear
additive package. A premium oil contains a better anti-wear package which prevents break-in.
Break-in is, after all, merely controlled wear.

In addition to metal surfaces in contact and wearing to fit, thermal expansion and contraction is
important for a properly broken-in engine.

Metal surfaces in contact???? You mean galling?.........

[blykins]

When breaking a flat tappet engine in on the dyno, the engine will change tone as the rings seal up.

Yep.

[blykins]

Note to the OP ... The ONLY difference between a PROFESSIONAL and a gifted AMATEUR has nothing to do with talent but, simply that the professional gets paid and possibly does it for a living.

.....and the experience level, based on how many times we've done it.

[Walter R. Malik]

Note to the OP ... The ONLY difference between a PROFESSIONAL and a gifted AMATEUR has nothing to do with talent but, simply that the professional gets paid and possibly does it for a living.

.....and the experience level, based on how many times we've done it.

I am good friends with a guy who has built 6 or 7 engines a year for the past 20 years ... he is an electrician by trade.

BUT, he does get paid for them.

[turbo2256b]

Ford came up with about an 8 hour break in procedure as they lost to many engines down the line on testing to be done after the break ins.
These break in runs were similar to one a guy that worked for moroso explained to me back around 66/ 67 to do on the street

[redliner]

Note to the OP ... The ONLY difference between a PROFESSIONAL and a gifted AMATEUR has nothing to do with talent but, simply that the professional gets paid and possibly does it for a living.

Guess I can't post my opinion since I am just a hobbyist.

LOL

Randy

BWAAHAAHAA!

[bentvalves]

Ford came up with about an 8 hour break in procedure. These break in runs were similar to one a guy that worked for moroso explained to me back around 66/ 67 to do on the street

so spill the beans.

[ProPower engines]

I will get everything ready and as closely timed as possible oil primed and everything else that needs doing ready to fire.
Fire up bring RPM up to 2000 and hold till it gets temp while setting the timing close enough to break in.
A series of light load pulls while watching the blow by meter till it gets to below 2 inches.
Reset total timing depending on its requirements then shut down and check everything like valve lash head bolts/studs etc etc while hot.
Now run again and after a series of light loads watching the blow by meter get to 0 then shut down.
Make sure everything is good for the 1st pull then hit it.

[jake197000]

dont have a dyno but prelube it,start it run it at 1800 or so set timing go drive it fairly hard with long decels.stop recheck things and run it .if its built right its pretty much broken in shortly after starting it.millions of new cars are sold every year,including high performance ones.you buy em and drive em no problems.oh ya change the oil after the so called break in.just dont get it hot.

[GRTfast]

http://www.mototuneusa.com/break_in_secrets.htm

This guy has put a lot of time and testing into his method. A few AMA supersport and superbike engine builders I knew back in the day used it with success. The main idea is to build a lot of cylinder pressure as soon as possible.

[BobbyB]

What about flat tappet and no dyno? What is the best way to seat new ring in the car after breaking in the cam?

[ProPower engines]

What about flat tappet and no dyno? What is the best way to seat new ring in the car after breaking in the cam?

Drive it like you stole it
The dyno simulates higher loads on the engine like its in the car just without everybody watching you drive the car.
Guys seem to think after the 1st fast idle time its all good but them rings need to be under load to bite into the cyl.'s and seat correctly. Moderate throttle in higher gears will do the same thing but for FT stuff that extended idling of a fresh engine can ruin a can in a hurry from lack of lube and that slow drag over the nose.