Dark Horse break in period?

[Deleted member 63333]

Since my Dark Horse was delivered to me I did not get any info, not that I needed much, pretty sure I knew more than the salesman.

I read somewhere of a break in period but forgot how many miles, 5000? Stay under 4k?

I played around some with it after washing the travel bugs off and installing my wheels. BIG difference between my 24 GT with the 3.55 rear and this pony with 3.73. Way more punch for sure, and that was playing under 4k RPMs. Got on hwy, and noticed 6th gear is a dog. But, who needs that unless its a road trip I guess.

Any tips from DH owners would be appreciated! Im stoked, cant stop looking at it

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[Starship Enterprise]

Break in shouldn't be different than GT. Go easy for 1,000 miles, vary RPM's, especially on highway. Apparently the worst thing you can do is drive extended periods at one steady RPM.

 

[Frogdog1]

^^^That's what I did with my GT and it uses zero oil. Drove it right at 400 half interstate and half twistie miles today and the highway was averaging 85 mph+ in holiday traffic. Still got 25.0 mpg and no oil used. Ran her up to 100+ now and then to get away from the idiots driving above their skill level. No po po out. Guess they gave up.

I just broke mine in the traditional way like Starship said above, then romped it increasingly after 1000 miles when I wanted.

 

[LouG]

Two new cars I bought involved a flight to get them and an 750km trip home. But I made a point of accelerating then engine braking every so often to work the rings and get oil into them.
They were fine.
With other cars I just drove normally with the occasional run up to two thirds of redline for the first 1000km

 

[GregB-Dark-Horse]

I have over 11,000 kms on mine now in it's first season this year, I did no specific break in procedure other than not hitting the rev limiter for the first 1000 kms or so and varying the rpm loads. I did not drive it at one speed on the highway until it hit about 4000 kms.

No issues so far, all good.

 

[tktrain]

As the old saying goes, break it in easy and it will run easy, break it in hard and it will run hard. But that was 40 years ago. I specifically asked about break in periods when I took delivery of my 2025 DH. The guy seemed to have a very solid understanding and he called the service manager to verify. Basically, they said the tolerances on these engines have improved to the point that there essentially no break in required. He also said the PCM won't allow you to abuse it until some miles have been put on the odometer. I noticed a distinct change iny seat of the pants dyno after about 100 miles. No oil use so far, but I'll change the oil at 500 and see what's in there.

 

[Skye]

https://www.mustang7g.com/forums/threads/break-in-period-rpm.167805/#post-3370179

This previous post references some comments I've made in other threads.

 

[Ryunker]

Since my Dark Horse was delivered to me I did not get any info, not that I needed much, pretty sure I knew more than the salesman.

I read somewhere of a break in period but forgot how many miles, 5000? Stay under 4k?

I played around some with it after washing the travel bugs off and installing my wheels. BIG difference between my 24 GT with the 3.55 rear and this pony with 3.73. Way more punch for sure, and that was playing under 4k RPMs. Got on hwy, and noticed 6th gear is a dog. But, who needs that unless its a road trip I guess.

Any tips from DH owners would be appreciated! Im stoked, cant stop looking at it

Get in and drive the damn thing, it will easy go 200k without any issues.

 

[LouG]

As the old saying goes, break it in easy and it will run easy, break it in hard and it will run hard. But that was 40 years ago. I specifically asked about break in periods when I took delivery of my 2025 DH. The guy seemed to have a very solid understanding and he called the service manager to verify. Basically, they said the tolerances on these engines have improved to the point that there essentially no break in required. He also said the PCM won't allow you to abuse it until some miles have been put on the odometer. I noticed a distinct change iny seat of the pants dyno after about 100 miles. No oil use so far, but I'll change the oil at 500 and see what's in there.

Break in is not about tolerances in things such as bearings. That went out with babbit bearings. It's about correctly wearing in the rings to provide optimum sealing and oil control.
The hard break in BS started from race engineers who don't have time to break in over 1500kms when they have a race next weekend, so it's done quick and dirty because they know they'll be rebuilding it well before a normal owner would accept.
A test done on two new Honda 250 engines showed the difference in ring gap between the two techniques. The hard break in engine had twice the ring gap of the correctly done engine.
That is prematrure wear. Aka oil burning earlier in it's life.

 

[hal26]

One thing that many of you may not remember is that you are breaking in the entire CAR....not just the motor. Brakes, transmission, rear end etc. That old BS advice stating run it like you stole it is an old wives tail.

 

[Starship Enterprise]

even new tires require break-in...

 

[LouG]

even new tires require break-in...

Hell yes. The number of bikes that are dropped after a tyre change is amazing. A smidgeon too much throttle leaving the tyre shop often ends in tears.

 

[Brevin]

I think a lot of people take the break in too seriously. Most of them are not mechanically inclined and don’t work on cars or build engines/transmissions.

Vary the engine RPM, seat the rings quickly, give the clutch/trans a few miles before you abuse them too much. And good to go. 1k miles is excessive IMO and you risk not getting a good ring seal if not done quickly. The reality is though, it’s probably fine no matter how you break it in. Manufacturing tolerances are light years better than they used to be.

My 25 made 1106whp with 250mi on the odometer. Not a drop of oil burned.

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