I'll need to re-break-in my new engine, any suggestions?

nondual

Member
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2007 Mazdaspeed3
I've heard so much conflicting info about this that it's maddening.

The first time, I drove it like I'd stolen it, so to speak. I never red-lined it (ok, accidentally a few times), but I definitely came at it hard. I've been told you need to do that to get maximum power out of the engine.

Others say you need to baby it.

Suggestions?
 
drive it notmally, give it some load from time to time and shift often

This is my personal suggestion and i don't know how it will work out, but i'm at 50k with a strong running engine
 
read the manual, do what it says. they didn't put that stuff in there because it's fun to write extra pages
 
jred321 said:
read the manual, do what it says. they didn't put that stuff in there because it's fun to write extra pages
I've been told that they suggest going easy because it's the most conservative policy and best affects durability, therefore reducing warranty repairs. That doesn't mean it's in the best interest of your overall power AND durability. I mean, isn't that why the thing also runs so rich? Durability over power?
 
JCell said:
drive it notmally, give it some load from time to time and shift often

This is my personal suggestion and i don't know how it will work out, but i'm at 50k with a strong running engine

I'll be driving it in LA this time, so yeah, lots of shifting and different rev ranges.
 
nondual said:
I've been told that they suggest going easy because it's the most conservative policy and best affects durability, therefore reducing warranty repairs. That doesn't mean it's in the best interest of your overall power AND durability. I mean, isn't that why the thing also runs so rich? Durability over power?

i would think the ECU has more to do with power than how you break in your engine. when you break in your engine you want everything to seat properly, bed properly, all that fun stuff. if it would make you feel better you could reset your ecu after breakin period so it relearns. i've had luck just driving normally during break in and following the manual's instructions. if you blew your engine in a few months though i would think maybe your break in approach the first time wasn't the best, unless it was a different reason that you blew your engine (like upping boost or playing with other things)
 
jred321 said:
i would think the ECU has more to do with power than how you break in your engine. when you break in your engine you want everything to seat properly, bed properly, all that fun stuff. if it would make you feel better you could reset your ecu after breakin period so it relearns. i've had luck just driving normally during break in and following the manual's instructions. if you blew your engine in a few months though i would think maybe your break in approach the first time wasn't the best, unless it was a different reason that you blew your engine (like upping boost or playing with other things)
Read carefully: I didn't 'blow my engine' - the tranny/motor mount broke. The engine's fine, except that I had to get the manifold switch replaced just like everyone else (P2006 error). I also switched to Mobil 1 after 1300 miles (when I first got the CEL and had to bring it in anyway).
 
jred321 said:
i'm confused then. do you still have the same engine you always did?
They're replacing it even though they don't technically need to. I think it's a 'good-faith' gesture. The engine was still running last time I saw it, and the tech confirmed that it still runs. I think they're extremely embarrassed that it happened and are saving face by doing a complete replacement of the drivetrain.
 
ah that clears things up. i still vote for drive according to the manual. any gains you could possibly see by getting the engine to break-in in a more performance oriented way (the only real benefit i can see would be a slight bump in static compression if things sealed better) would be minimal and easily outweighed by a change in boost or air/fuel. what you want from a break in is for the piston rings to seal. they will seal well using the manual method, might take longer than the drive it hard early method some people suggest but it's safer
 
jred321 said:
ah that clears things up. i still vote for drive according to the manual. any gains you could possibly see by getting the engine to break-in in a more performance oriented way (the only real benefit i can see would be a slight bump in static compression if things sealed better) would be minimal and easily outweighed by a change in boost or air/fuel. what you want from a break in is for the piston rings to seal. they will seal well using the manual method, might take longer than the drive it hard early method some people suggest but it's safer
The other thing is that it really seemed that my power dropped as time went on. Maybe it's due to the way I drove it, or it could have been the tranny working loose (parasitic power loss?), or the fact that it had the CEL light on for at least 5k of the 7k miles I put on the thing.
 
Nondual - can you please enlighten us as to what the actual failure was? Did the famous bolt back out, or did a component actually break? If so, what part broke? Pictures of the failed part would be extremely valuable. Hopefully your dealer will show you the broken part if you ask nicely.
 
Rotus8 said:
Nondual - can you please enlighten us as to what the actual failure was? Did the famous bolt back out, or did a component actually break? If so, what part broke? Pictures of the failed part would be extremely valuable. Hopefully your dealer will show you the broken part if you ask nicely.
The dealer tech told me it wasn't a bolt backout, but I'm skeptical. He said the thing just flat out broke. If it did, maybe the loose bolt caused the stress that broke it and that would be difficult to differentiate.

I plan on asking the service tech flat out how to prevent this in the future, and I'll probably upgrade the mounts as my very first upgrade post-warranty (maybe even while within warranty).
 
nondual said:
The other thing is that it really seemed that my power dropped as time went on. Maybe it's due to the way I drove it, or it could have been the tranny working loose (parasitic power loss?), or the fact that it had the CEL light on for at least 5k of the 7k miles I put on the thing.

there's also the fact that the more you drive it the more you get used to the power. when i first got my car it seemed really fast at first, then after a month or two it was like meh. then when i did exhaust and then again with the reflash it was like whoa it's fast again. now it's back to meh. then next set of mods it will be fast again for a few months and then back to meh. without something measurable to say that it was definitely slower it's tough to say that it actually was slower and not that it just felt slower
 
Unreliable butt dyno?

Do you reflash everytime you mod? What's the process again? Disconnect battery and press brake to the floor?
 
nondual said:
The dealer tech told me it wasn't a bolt backout, but I'm skeptical. He said the thing just flat out broke. If it did, maybe the loose bolt caused the stress that broke it and that would be difficult to differentiate.

I plan on asking the service tech flat out how to prevent this in the future, and I'll probably upgrade the mounts as my very first upgrade post-warranty (maybe even while within warranty).
The reason to see what specifically broke is to know what to upgrade. The "mount" consists of a compliant piece (rubber, urethane, etc.) and then the surrounding brackets, bushings, and bolts. "Upgrading" the mount might not replace the part that broke. Also, looking at the broken piece could help determine if this is an isolated manufacturing defect, assembly error, or design problem. Information for the community is invaluable.
 
jred321 said:
there's also the fact that the more you drive it the more you get used to the power. when i first got my car it seemed really fast at first, then after a month or two it was like meh. then when i did exhaust and then again with the reflash it was like whoa it's fast again. now it's back to meh. then next set of mods it will be fast again for a few months and then back to meh. without something measurable to say that it was definitely slower it's tough to say that it actually was slower and not that it just felt slower

I totally agree..(friday)
 
nondual said:
Unreliable butt dyno?

Do you reflash everytime you mod? What's the process again? Disconnect battery and press brake to the floor?

yep, the good ol butt dyno and it's lying ass. reflash for me means redoing the air/fuel map, or in my case having someone who knows what they're doing do it. ideally you should have it done after every mod but small things the computer is smart enough to figure out on its own. not sure if they have that for the MS3 yet though.

to reset the ecu you disconnect the negative terminal for a few minutes and pump the brake a few times
 
They replaced your entire motor due to a manifold switch problem? That doesn't make sense. But if its fresh motor, meaning its never been fired up or driven less than a few miles, you need to break it in like you want it to respond to your foot in the future. By that I do not mean redline visits or needless idling. Your goal is enough load to seat the rings.

The manual will of course tell you not to for like 1,000 miles, but the rings are not seated properly before that mark or whatever it says, they never will be.

I've purchased three new cars so far and broke them in as stated above. Two of those engines were completely rebuilt after 200,000 + miles of trouble free service. No obvious signs of damage to the bottom end at teardown, just normal expected wear for that amount of mileage.
 
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DAWIV said:
They replaced your entire motor due to a manifold switch problem? That doesn't make sense. But if its fresh motor, meaning its never been fired up or driven less than a few miles, you need to break it in like you want it to respond to your foot in the future. By that I do not mean redline visits or needless idling. Your goal is enough load to seat the rings.

The manual will of course tell you not to for like 1,000 miles, but the rings are not seated properly before that mark or whatever it says, they never will be.

I've purchased three new cars so far and broke them in as stated above. Two of those engines were completely rebuilt after 200,000 + miles of trouble free service. No obvious signs of damage to the bottom end at teardown, just normal expected wear for that amount of mileage.
No, no, no. They replaced the engine after it broke free from the tranny/motor mount. Previously they replaced the defective switch.

Will synthetic oil after the break-in period also help? That's what I've been doing.

Edited to add: The car is currently at the dealer and will have the drivetrain replaced before I get it back. Hence, I'll have to break-in again.
 
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