I'm not sure. What do you guys think? :rofl2:

I would go with "a lot of people" as they are obvously smarter. A lot of people voted for the current President as well as the latest "American Idol". I personally think the intelligence of the masses is under-rated.

haha... classic. That was a good one, Tree.

Power to the People! :D Granted, the "people" who voted for (and watch) American Idol are girls from the age of 7 - 15 with access to cell phones and texting (yes I blame the parents).

Maybe we should ask these same children how we should properly break in our engine?

Based on the opinions I have seen across different forums for different cars and motorcycles, the more knowledgeable people seem to say this: break it in easy for longevity, break it in hard for power. I went with with a little of both. I avoided WOT and 6500+ rpms for the first 1000 miles or so, but still drove in a "spirited" manner around town.

Nissan obviously recommends a break-in procedure for a reason, but doesn't tell us the reason. The question is whether that unidentified reason - which, from a practical standpoint, is most likely for longevity purposes - aligns with your own goals. Sometimes it does, sometimes it doesn't. But arguing that the manufacturer's recommendation is the only correct/safe/best way to do something, simply because it's in the manual (and without knowing why it's in the manual), is a bit short sighted in my opinion.

We call that "anecdotal evidence", and in the scientific community it has zero statistical significance.

Nissan is going to know better than anyone... if that's what they say. Do it.

Otherwise you might end up with a potentially bad situation...

Why would the manufacturer's recommendations NOT be the best way to handle THEIR product? I don't think I necessarily need to know "why" it's stated in the manual to follow. They're the experts. They're who I follow.

Now if I was an automotive engineer who did some testing on what results proper break in (under 4k rpm) yields, maybe I could question what they say. With how you broke in your car (1/2 and 1/2), what evidence do you have that you helped or hindered the longevity/performance/power/etc of your engine? Without proper proof or proper testing, any results you have are circumstantial. If you do have proof and did tear down your engine or did other forms of testing, I stand corrected and will fully accept your claim.

But until then, I will follow what my manufacturer recommends.

Because the manufacturer's goals are not always the same as a car enthusiast's goals. It's possible, for example, that Nissan wants us to break-in the engine in the way that causes the fewest warranty concerns down the road, even at the expense of some additional power. I'm not saying that is the case, but hopefully you see the point. We simply don't know for sure. That clearly doesn't bother you, and that's fine. But it's pretty ironic that we have a forum dedicated to modifying our cars (i.e. changing what the all-knowing expert manufacturer gave us), but then we aren't even interested in questioning their suggested break-in procedure.


I have no evidence, nor do I claim that my method helped or hindered anything in any way. That was not the point of my post (see above for the point).


I am not trying to convince you otherwise, so go for it. :tup:

Look, you want your car to last, you want it to be in the best shape, you want no mechanical trouble! Doing the "speed limit" the first 1K, will keep the engine under the 4,000 revs!

i guess i took my friends' advice and started driving to redline in first (the little light showed up indicating i was in the 8,000 rpm, which i did on accident a few times). is this bad for my engine??

Some friends you have! You're either very foolish or must have $40,000 to burn. 8,000 rpm in fisr gear is car abuse. You're endangering both your warranty coverage and your car.
Use your head and follow the manual.

That's is precisely how I view your posts, in this thread!

Care to explain? That's not a very thoughtful or helpful way to voice your opinion.

Don't forget a portion of their "recommendations" are tied to safety. Part of the reason they want you to baby the car is so that you don't wrap it around a tree within the first 100 miles because you're not used to the car yet. Also, if you drive it like you stole it right from the start you risk developing heat spots on certain parts of the internal components and that can lead to future warranty claims. Although, this is highly unlikely these days.

An engine isn't 'new technology' but the way it's designed and manufactured are. With the tight tolerances and materials engines are built with today it's easy to get 100k miles (or much more) from an engine without so much as a worry (there are exceptions I realize).

The basics of a proper break-in are simple. Fluids->Proper Temps->Increasing Load->Not Overheating->Proper Cool Down

What I do for all my vehicles:

1. Ensure ALL fluids are correct and at the proper levels before each drive.
2. Allow the car to warm up properly by driving around (calmly) until at normal operating temps. Don't just freeway cruise though.
3. Slowly ease into giving the vehicle more load. Rev it a little higher each time you go out but no need to thrash it. Also use engine braking to ensure proper seating of rings.
4. Drive moderately aggressive like this for 10-15 min then drive like your grandma for about 10 min and park the car. Let it cool down fully.
5. Continue this until approx. 500 miles then on step 3 give it full gas to redline, just once or twice every 3-4 times you drive the car. Run through the gears to legal speed.
6. Once you get to 750 or so miles there's really nothing more to do.

Don't forget to change the engine oil & filter. I go 600 miles for motorcycles and 1,800 miles for cars/trucks before first oil change. If it takes you 12 months to go 1,800 miles in a new car then change at 3-4 months.

I'm still a firm believer in the need to heat cycle a new engine. It's probably not needed these days but as another member said, do what makes you comfortable. Remember that you're not just doing the break-in on the engine, you're doing it for the entire car.

Do what works for you but it's nothing to really worry over.

370Z forum = scientific community LOL

Like I said, subjective subject matter...

I guess I can somewhat see your point. If someone bought a brand new Z with the sole purpose of modding it be a high powered drag car from the get-go, then going against the manufacturer's recommendations might be plausible. But again, my point is, unless there's real proof that driving it beyond 4k rpm does yield SOME benefit (in your case, power), why do it based on circumstantial evidence? For what you know, there's still a chance you "could" be hurting your car in the long run, correct?

The only thing that seems more "solid" to me is what a manufacturer recommends.... unless some other automotive engineer can speak to the pro's and con's of driving under or over 4k rpm for the first 1200 miles, I think (again this is just my opinion) the best thing to do would be to follow what Nissan recommends. Wouldn't some form of Longevity appeal to 90% of car owners?

Again, I respect your opinion and I see some of your points. We can respectfully agree to disagree on some points (not all). I'm cool with that.

I respect your methods... and I assume (hope) that you have concrete evidence/support/proof that your methods have worked. If so, great. If not, then I question WHY you are doing it this way.

But you're right, in the end, do what you want to do. For me, my proof, though it may be circumstantial but good enough for me, is that all my cars I have owned since new, I have followed the manufacturer's recommendations, and 2 of the 6 have lasted 140k or more, another one on the verge of 100k, and the others will be well on its way ;)