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So how long is the break in period for this car? Just wondering for when I get one so that I don't go too hard on it too early and wreck something.
 

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There are many opinions on this. I to wondered. The owners manual if I remember correctly says 2000 miles. However, on this forum you will probably find more people in the camp of no break in period. Personally I didn't drag race it out of the box but I certainly didn't baby it either, just too hard to not have fun with it. As many have said here, I wouldn't recommend babying it.
 

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You HAVE to get on it at least a fair amount to seat the rings. Many people including myself are in the camp of, "don't be afraid to get on it, but no prolonged hard driving." From what I can see, most sports car break-ins tell you to use varying degrees of throttle up to 50% and up to 4k rpm. The reason they say to stay below 50% AND 4k is because IF there are manufacturing defects, those defects can cause hot spots if not smoothed out gradually. However, if you are TOO gentle, the cylinders will glaze before the rings are properly seated.

If you are the cautious type, then I'd recommend following the 50% throttle/4k rpm for 500-1000 miles. DO NOT let the engine run at a constant RPM for a long period, ie cruising on the highway. Let it buck, but don't romp on it. It NEEDS high cylinder pressure to seat the rings.

If you are a bit braver and want to make sure the rings get good and seated, be semi gentle for a few dozen miles to knock down any possible defects, then give it to her for short bursts. Just don't tow anything or try to find the top speed for the first 1k miles or so. Short runs to 60 are ok (imo), and as the miles rack up, so can the speed.

So to reiterate, don't be gentle, but don't be TOO hard for the first 1k miles. Too gentle is just as bad as too aggressive.
 

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At 750 miles and my average mpg is 16.3. It has seen redline more times than not.
 

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Im at 1200 miles Highest rpm reached is 3500 and have not used sport mode yet.. i will baby it instill after first oil change at 4000 k
Babying it is just as bad if not worse than abusing it.
 

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Im at 1200 miles Highest rpm reached is 3500 and have not used sport mode yet.. i will baby it instill after first oil change at 4000 k
Your piston rings have already glazed the cylinder walls. I am willing to bet money that if you compared a properly broken in 2.7L engines compression to yours, you would be down about 20-40 PSI. This is exactly why I would never buy a performance car used, people dont know how to properly break in motors. No one can ever give any solid reason as to why you should baby a motor while breaking it in, ive never once heard a good logical or mechanical reason to do so.
 

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You HAVE to get on it at least a fair amount to seat the rings. Many people including myself are in the camp of, "don't be afraid to get on it, but no prolonged hard driving." From what I can see, most sports car break-ins tell you to use varying degrees of throttle up to 50% and up to 4k rpm. The reason they say to stay below 50% AND 4k is because IF there are manufacturing defects, those defects can cause hot spots if not smoothed out gradually. However, if you are TOO gentle, the cylinders will glaze before the rings are properly seated.

If you are the cautious type, then I'd recommend following the 50% throttle/4k rpm for 500-1000 miles. DO NOT let the engine run at a constant RPM for a long period, ie cruising on the highway. Let it buck, but don't romp on it. It NEEDS high cylinder pressure to seat the rings.

If you are a bit braver and want to make sure the rings get good and seated, be semi gentle for a few dozen miles to knock down any possible defects, then give it to her for short bursts. Just don't tow anything or try to find the top speed for the first 1k miles or so. Short runs to 60 are ok (imo), and as the miles rack up, so can the speed.

So to reiterate, don't be gentle, but don't be TOO hard for the first 1k miles. Too gentle is just as bad as too aggressive.
What exactly is a hot spot and why is a gentle break in better than a hard break in in regards to hotspots? Honestly im just curious because I dont know of any good reason to break an engine in lightly and Id really like to understand the philosophy behind it. I definitely understand prolonged high RPMS, but I cant think of a single reason not to redline a new motor besides the old philosophy of my father telling me to break the motor in gently.
 

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What exactly is a hot spot and why is a gentle break in better than a hard break in in regards to hotspots? Honestly im just curious because I dont know of any good reason to break an engine in lightly and Id really like to understand the philosophy behind it. I definitely understand prolonged high RPMS, but I cant think of a single reason not to redline a new motor besides the old philosophy of my father telling me to break the motor in gently.
By gentle, I don't mean babying. I also dont follow the gentle proceedure, as I said. However, in the event that there is an area of your cylinder wall or a bearing surface that is rougher that other areas from the maufaturing, the added friction of a hard break-in on that extra rough spot could cause the metal in that area to heat to a point of causing a metallurgical change. IMO, its a long shot in modern engines which is why i follow the hard break-in.

The chance of ot happening is still there, especially in the first few miles, though. I imaging that's why they don't tell you to abuse it.
 
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Discussion Starter · #14 ·
You HAVE to get on it at least a fair amount to seat the rings. Many people including myself are in the camp of, "don't be afraid to get on it, but no prolonged hard driving." From what I can see, most sports car break-ins tell you to use varying degrees of throttle up to 50% and up to 4k rpm. The reason they say to stay below 50% AND 4k is because IF there are manufacturing defects, those defects can cause hot spots if not smoothed out gradually. However, if you are TOO gentle, the cylinders will glaze before the rings are properly seated.

If you are the cautious type, then I'd recommend following the 50% throttle/4k rpm for 500-1000 miles. DO NOT let the engine run at a constant RPM for a long period, ie cruising on the highway. Let it buck, but don't romp on it. It NEEDS high cylinder pressure to seat the rings.

If you are a bit braver and want to make sure the rings get good and seated, be semi gentle for a few dozen miles to knock down any possible defects, then give it to her for short bursts. Just don't tow anything or try to find the top speed for the first 1k miles or so. Short runs to 60 are ok (imo), and as the miles rack up, so can the speed.

So to reiterate, don't be gentle, but don't be TOO hard for the first 1k miles. Too gentle is just as bad as too aggressive.
What If I have no choice in regards to the highway? It's the only way to get to my work
 

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What If I have no choice in regards to the highway? It's the only way to get to my work
Try to make sure you vary the RPMs still. Try to slow down and then accelerate back up to the speed limit. Stuff like that. When the highway is clear (be safe about it) slow down to 30 mph and then speed back up to the speed limit. If you are driving faster than most people, you will at some point have a slower person in front of you. Once they are out of your way, accelerate those ten MPHs harder than normal.
 

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What If I have no choice in regards to the highway? It's the only way to get to my work
Try to make sure you vary the RPMs still. Try to slow down and then accelerate back up to the speed limit. Stuff like that. When the highway is clear (be safe about it) slow down to 30 mph and then speed back up to the speed limit. If you are driving faster than most people, you will at some point have a slower person in front of you. Once they are out of your way, accelerate those ten MPHs harder than normal.
You can also use the paddle shifters to switch between gears. I'm not an engineer, but one of the reasons I think you want to vary the RPMs during break in is: A) to put the engine through varying heat cycles, and B) because the connecting rods stretch a little bit. At higher RPMs, they stretch more, obviously. When the rings wear into the cylinder walls, they create a ridge at the top. If you stay at low RPMs the entire time the engine is wearing the most, this ridge will be lower than if you run it at a higher RPM more often. Imagine what happens if you let it create this lower ridge, then once you are satisfied that it's past it's gentle break in period and you jump on the throttle. The rods will stretch, the rings will slam into that ridge, and they won't be happy about it.
 

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Mine was driven 200 miles from a dealer transfer down the freeway so probably royally F'd for life. :p
 

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Mine was driven 200 miles from a dealer transfer down the freeway so probably royally F'd for life. :p
RIP ike's car... :(

Yeah right. Like that think was babied at all during that drive...
 

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You can also use the paddle shifters to switch between gears. I'm not an engineer, but one of the reasons I think you want to vary the RPMs during break in is: A) to put the engine through varying heat cycles, and B) because the connecting rods stretch a little bit. At higher RPMs, they stretch more, obviously. When the rings wear into the cylinder walls, they create a ridge at the top. If you stay at low RPMs the entire time the engine is wearing the most, this ridge will be lower than if you run it at a higher RPM more often. Imagine what happens if you let it create this lower ridge, then once you are satisfied that it's past it's gentle break in period and you jump on the throttle. The rods will stretch, the rings will slam into that ridge, and they won't be happy about it.
You can also do this, but you want to be careful and monitor what the RPMs are in a lower gear. You do not want to have it at sustained RPMs over 4000.

For reference, I am an engineer, and pretty much what is said above by BOT is correct, just don't sustain the high RPMs.
 

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He explains his reasonings quite well. He does seem to have some valid information to back it up too.
Unfortunately There is no way I kept her under 4000 rpms and half Throttle for the first 1000 miles. But I'd say it was all in moderation, not like I was doing WOT every time out. Got close to 6000 miles now, started running tune around 2500 or so(93 octane Unleased tune) and she runs great. No matter what happens to my or anyone else's car in the future you'll never know if it had anything to do with how you did your break-in. So choose a break-in technique your comfortable with and never look back or bother worrying about it and enjoy your new car.
 
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