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Break In Procedure

I am breaking in my Boss with conventional oil. Changed out the synthetic factory fill at 100 miles. Replaced with 8 qts. Valvoline 10W-40. Will run to 1000 miles and change again with the same Valvoline 10W-40. AT 3000 miles I will go back to synthetic. I am driving the car hard from the get go. Not shy about tach-ing it to redline. Trying to vary the rpms constantly. What do you guys do for break in?
 
Yikes!!! I am not sure that you should have changed to 10W-40, do you know what your oil pressure is? I have read the stuff about conventional vs synthetic during break in, but I figure the Ford engineers knew a little when they spec'd out this oil. Unconfirmed rumor is Ford put some sort of break-in enhancer in the original oil - I do not know if this is true and/or what it is. Can anyone confirm yes or no on this?

I only have 600 on mine, still has the original 5W-50 in it. I was going to change at 1000 but may do 2000 and I wil use the Ford 5W-50. I kept it below 6K until 100 miles (but avoided lugging it). From there I had/have no issue with running it to redline but I don't do it constantly while driving, same vary the rpm and run up/down through the gears. If I run it up to redline through the gears (or do a high speed run), I follow that with a couple minute cruise to cool it back down, my average crusing rpm is 3500-4000 - I still avoid lugging it. Trying to do the whole high cylinder pressures to increase the pressure behind the rings to help them seat, blah blah. When I get it home in the garage, I pop the hood and turn on a fan (directed at the engine compartment).
 

BLAZN BOSS

I dont think you would get the OK from Ford for what your doing. Conventional oil is on the way out, To give you the best example of the properties of synthetic oil is imagine you have a bag of marbles, all different sizes, thats what the molecules of conventional oil looks like.......where as the sythentic is all the same size........better distribution, better dissapation of accepting loads since the molecules are the same size. Sythentic doesn't burn like carbon oil does, doesn't even begin to sludge. I'm currious what advantage you feel that you gained by doing this? I'm going to use exactly what the fill cap says and at the intervals the manual says. These motors are built with race spec parts and with forged pistons etc tolerance are much better than the regular coyote engines. On the other hand, it's your car, you paid for it and if you feel thats what you want to do you have earned the right!
 
He isn't going to hurt anything. I heard the dyno oil seats the rings faster. You guys remind me of that commercial were the guy has special eyes, but with a special motor. Rev, rev with your special motor.
 

BLAZN BOSS

Well I have owned my own automotive machine shop and spent hours at the dyno............its a wives tale that ANY oil breaking in parts better than others..........The BIG difference is by products, protection and longevity........fosil oil loses.....PERIOD.
 
itrack said:
He isn't going to hurt anything. I heard the dyno oil seats the rings faster. You guys remind me of that commercial were the guy has special eyes, but with a special motor. Rev, rev with your special motor.

Come on is that the best that you can add? Tell us how you broke in yours, what oil do you use, first change, how frequent do you change it, how does tracking it change how you maintain it, do you change it every weekend you track, if you changed oil weight how did that affect your oil pressure? Give us some data.

I too have read the conventional vs synthetic arguments, just not sure I want to experiment on my Boss engine, thus I am deferring to the Ford engineers on this one until some engines get torn apart and wear established.
 
I guess I disagree with most of you guys. I have built plenty of engines over the years and the one thing they always say about break-in is DONT USE SYNTHETIC during break in. Synthetic does not allow the rings to seat properly. Even AMSOIL and Royal Puple make special oils (non synthetic) for break in. My DART block that I am currently building has the following break in instructions:

All short blocks must be broke in with Royal Purple 10W30 break in oil, engine must be primed before starting.

Start engine, run for 25-30 minutes at 2000-2500 RPM, let engine cool. Change filter, cut open filter and examine. If filter looks good, repeat engine break in with 2 more warm up cycles for 15-20 minutes at 200-2500 RPM. Check for leaks and adjust ignition timing as necessary. Change oil and filter. Drive car varying RPMs frequently over next 1000 miles of driving.

Also I picked 10W40 because I couldn't find 5W-50 in conventional oil. 10W40 seems like a nice compromise because the viscosity range is right in the middle of what Ford has specified. The other option was 20W50 which would have been a little too heavy for break in in my opinion. I know that might scare some of you guys, but it really shouldn't. I ran 5W-30 in my Lightning for years, because Mobile1 and the other Synthetic brands did not make 5W-20 at the time I bought the truck, and for a few years after. It is still humming along just fine after 10 years.

Here is an interesting link on break in procedures:

http://www.mototuneusa.com/break_in_secrets.htm
 
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GA
Here is an old thread with interesting info on break-in:

https://trackmustangsonline.com/boss-302-technical-forum/how-are-you-going-to-break-in-your-boss/


*This is regarding the same link as above. I guess we posted about the same time. It says it must happen within the first 20 miles, so I lost that opportunity since someone drove my car down from a dealership about 70 miles away.
 
Here are some interesting posts from new Mustang Coyote owners involving excessive oil consumption. I expect this is related to improper break-in, but I leave it to you to decide.

http://www.allfordmustangs.com/forums/2011-mustang-gt-tech/282088-how-much-oil-consumption-during-break-normal.html
 
All good links and info. Pretty much agree with the run it hard and vary the rpm's with limited extended redline. Have read the mototuneusa info and utilized that for lots of mx race engines (at the pro level), but those are engines that would be rebuilt long before there would be any wear or oil releated failures - not trying to get 50K miles out of them. So in this case I want the best of both worlds, most hp so am revving it and want it to last +50K miles so am deferring to Fords 5W-50 until proven otherwise. Their resources for chosing this specific oil for this specific engine exceeds mine.

I suspect the track guys (road or drag) will be the first to rebuild theirs due to running hard and needing maintenance, (this discludes somebody blowing up their engine) so maybe we will get some info out of them next year. Us street guys just need to change our oil and filters and kinda treat them like we are the ones that paid for them.
 
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Each to their own. It's your car and you have the option to break it in the way you think best. I go with the factory recommendations more often than not cause those engineers and techs are way smarter than I am and get well paid to be sure what they promote is correct.

Only deviation I did was I changed the break-in oil at around 2K just cause I think it makes sense to get rid of whatever debris may be sloshing around in there after the official break in period of 1K miles. Since I don't track mine and since the Boss capacity is 8.5 quarts, I felt perfectly comfortable running the original oil another 1K after the break in. I suspected (but have never confirmed) that the factory fill had some break in conditioners or additives and wanted to give them some time to be effective if they were in there. Since there is no real cost differential, I plan to continue to use MotorCraft 5W-50 synth going forward.
 

BLAZN BOSS

Oil doesnt alow rings to break in, the only oil near the first and second compression ring is there during the initial start up from the assembly of the motor. The bottom rings (the oil controll rings) dont allow oil up there, its their job, if it was allowed it would burn instantly during ignition fire and you would eventually have that gret big blue cloud following you. Break in of compression rings occur because of the crosshatch left by finish honing of the cylinder to get rind of the "crush" left behind by the boring bar . Ford, GM, Chrysler, BMW etc , mutlibillion dollar companies are slowly switching their cars to synthetic, corvettes, and other high high high dollar cars all sythentic. Grandmas oil will work yes, but the engineers that are paid to study, examine, teardown , research these oils have obviosly figured out that the best protection for their company and your car is now sythetic. If you really want to monitor whats going on replace your stock drain plug with a magnetic one.........look for the problems there. I know this debate could go on till we have no oil left on earth.
 
Wow. The engines are broken in from the factory so run them hard and vary your speed. Swapping oil in either direction is a waste of money. Of course I dropped mine after a thousand miles due to an old habit but I admit it was a waste of money. :)
 
MNG_BOSS302 said:
All good links and info. Pretty much agree with the run it hard and vary the rpm's with limited extended redline. Have read the mototuneusa info and utilized that for lots of mx race engines (at the pro level), but those are engines that would be rebuilt long before there would be any wear or oil releated failures - not trying to get 50K miles out of them. So in this case I want the best of both worlds, most hp so am revving it and want it to last +50K miles so am deferring to Fords 5W-50 until proven otherwise. Their resources for chosing this specific oil for this specific engine exceeds mine.

I suspect the track guys (road or drag) will be the first to rebuild theirs due to running hard and needing maintenance, (this discludes somebody blowing up their engine) so maybe we will get some info out of them next year. Us street guys just need to change our oil and filters and kinda treat them like we are the ones that paid for them.

Yes really, thats what I had to add. Ford built this car to rip ass at the track. The motor was tested all of the 2010 race season. I doubt very likely that we are going to see any motors blow in the near future that aren't user error. Sorry but I'm not going to sugar coat my posts to make guys who want to treat this car like a show queen sleep better at night. It is what it is but if your Boss isn't seeing track time your wasting the car.
 
itrack said:
Yes really, thats what I had to add. Ford built this car to rip ass at the track. The motor was tested all of the 2010 race season. I doubt very likely that we are going to see any motors blow in the near future that aren't user error. Sorry but I'm not going to sugar coat my posts to make guys who want to treat this car like a show queen sleep better at night. It is what it is but if your Boss isn't seeing track time your wasting the car.

Your non-sugar coated post is not an issue, it was just devoid of any good info. Answering the questions - what did you do for break in, what oil do you use, how frequent do you change it due to tracking, if you changed to a different weight did that affect your oil pressure or temp - would have provided good information.

I don't think us guys that are not tracking them are "wasting" the car - we may not be using it's full capabilities. But seeing that Ford estimated that less the 10% of them will ever see the track, would you prefer nobody bought them if they aren't going to track them - leaves alot of cars sitting in the show room (being wasted for sure).
 
Mike, oil is like religion/politics, everyone has there opinion and preference. Telling someone they are going to blow thier motor up sooner due to how they broke it in or if the car see's track time is akin to telling someone they are going to hell. Its just poor taste. I am running Rotella T6 5-40 in all of my cars. I change my oil in the cars that see track time every 7k or 2 track weekends which ever comes first. I'm changing my Factory oil this week with 6700 miles in preperation for a track day. I was told to leave it in by a Ford tech that stated the oil had break in additives from the factory. Just an FYI but a 5-40 will flow more oil than a 5-50 once the motor is warmed up. If you did any research on the Motorcraft 5w50, it sheers very quickly to a low 40 high 30 weight with very small usage. Running a proven 5w40 that doesn't sheer so quickly makes a moot point. Please refrain from commenting on track reliablity until you see some track time bud.
 
Intersting post for an engine already broke in hum let me just add this I have built engines all my life you first start it with a high idle 15 min is the breakin time you will hear the rings seat completely then you change the oil add new and you are ready to go thats as simple as it is these are all put on a run in so really is no worries at all and with the billet parts inside them just flat out drive the car your fine there is no trick to these engines at all. If you dont believe me on this then build a motor and fire it up with a high idle and listen right at 15 min idle will change and sound completely different then shut it down change oil allow to cool and go.
 

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