Break In Philosophy Poll

Why not follow the instructions in the OM? (usually something like "don't exceed 5000 RPM for the first 1000km")

 

engines have been around so long, and so many people have built them and found the things that work, thats its really not that complex. The rings to begin with, are the first highest priority to work out. If they don't seat right away, they usually never will. As soon as the engine is running and been heated and shut down to check for leaks, timing adjusted, carbs at least roughly synced, if its carbed, but not wasting much time more than to cycle the fan once or twice, if all is well mechanically, it needs to be driven, and accelerated at full throttle through its mid rpm range, back off with no throttle, and repeat many times. The rings have to be gassed into the walls and ran in hard to seat before they have a chance to glaze. Then you can go fine tune, play with carbs, readjust things, etc. But working the engine through its full range should take place in steps to seat in the crank and rod bearings over at least 500 miles before full rpm runs to red line take place. The Ferrari service manual seems to follow the same basic course as well, just that they want it done on a dyno by time in hours.

 

5 minutes, or 5 miles. No leaks, no sqeaks, drop the HAMMER!
With the proper wall finish, and polished bearings, the internals are smoother than the most carefull break in ever done. Tink for a minute, who drives a Top Fueler for a 2000 mile break in?
But that is only for the motors built in house.
For factory, I would take it easy for a bit, as they do not seal quite as well as a hand built one. Change the oil filter OFTEN. This gets the particles out of the oil, as the filters do not filter 100%. They have a bypass, and it is usually 10 lbs. Sometimes a little as 5 lbs. When they open, all of the particles start flowing toward the new bearings. We fire up new motors on a separate micromesh screen system. This assures clean oil, and a look at what was in the motor after it has ran a half hour. This will usually tell the exact condition of the internals.

 

And how often are these top fuel motors expected to go 100k+ miles? And how often are they rebuilt?

I just go by the manufacturer's recommendations and hope that the people who wrote them listened to the engineers that designed them.

 

Don't forget to stop every ONCE and a while, to pick up your buddies!!!! LOL!

*waving*

 

The engines are run on the bench to full power and the car is later driven. It is OK to blast off from day one but you would not be wrong by following the owners manual either. They actually told me this while at the tour in the Ferrari factory in Maranello.

HOWEVER, you MUST wait for the engine oil to come up to full operating temperature otherwise a tremendous amount of wear and tear will occur. This is true regardless of how many miles any car has on the clock.

aehaas

 

I think it won't hurt to drive as specified by the manual, and change the oil at 500 miles. It will be hard as hell, though, to drive it like that.

BTW, it was great meeting you Dale at Crystal Cove last weekend.

Dom

 

This is an interesting topic. I researched it a little before I got my 360 b/c in the past I've never been one to follow the factory recommendations too closely. My general philosophy, albeit not scientifically supported, is that you should break it in over the full rpm range and at different levels of stress so the motor is "use" to those parameters. But I managed to find 1 guy's break-in procedure who is an engine builder (supposedly considered an engine guru on one of the Supra lists) whose procedure is systematic. I'll try and find the link to the thread.

One guy picked up his brand new Z06 and followed this procedure on the way home from the dealership. His car dyno'd later at 365 rwhp. I saw the graph. Most Z06's dyno anywhere from 340-350. I think my Z06 (since gone) was right at 345 rwhp. Maybe he just got a strong motor. Anyway, this guy's philosophy has to do with systematically increasing load and stress on the pistons and rings with adequate cooling in between. In a sense "heat cycling" the motor.

From what I remember you start at about 10% throttle for about a 15-30 second burst and allow 1-2 minutes of piston cooling just cruising at nice even speed. You gradually increase by 10% increments until your last run is WOT for about 15-30 seconds. Most of this obviously has to be in 4th or 5th gear and you need a place with a lot of wide open road. But you don't want to shift in the middle of the burst. Stay in one gear. After it's over the motor is completely broken in. I did this with my 360 when I first got it. It runs great, but I have nothing to really compare it too. So I don't know if it really works. Maybe I'll get it dyno'd one day.

This is how this guy breaks in all of his newly built motors and gets very good power numbers and motors that are very reliable. Just another person's opinion to add to the controversy. In the end, it probably doesn't matter how you break in a modern engine except for waiting for the oil temp to get up to adequate temperature.

 

Warranty baby... warranty!

I say, drive a crap out of it. Let FNA or SpA pick up the tab if Luigi messed up during the build.

If it's gonna blow, it'll go before that "2 years/unlimited abuse" period expires.


-d

 

My understanding is that you need to see the run-in period is for the car as a whole instead of just for the engine. It is true that all manufactures, especially makers of high performance vehicles all run their engines on the dyno for a certain amount of time before the engine is actually put into the car. That doesn't cover the drivetrain, brakes, and suspensions etc.

 

The answer is in b/w the 2 extremes.

Street motors:

I vary engine speeds throughout the break in period; don't do a lot of highway crusing where you're at 4000 rpm for hours at a time - you're trying to etch the piston rings and walls against each other so they seal up tight, a lot of straight line crusing will glaze the cyl wall.

0 - 300 miles: if redline is 8ooo I don't exceed 6ooo for and take sections of road where you can vary load, gear, engine speed, etc and every once in a while, give it a full throttle blast to 6000 rpm, and let it decel too.

301-600miles: do the same as above but now up to 7000 rpm. Be dilligent to work the motor through a variety of loads, open it up once in a while.

600 miles : 1st oil change.

601 - 2000 miles: Do the same as above, but incrementally get closer to redline and hit redline a few times as you get to 1500 miles.

2000 miles: oil change # 2.

I consider it broken in after the 2nd oil change.

Enjoy.

Race motors:

10 heat cycles, beat it senseless.

 

In "ancient times" the cylinder walls were not fully processed when they came from the factory, so for the first 500 km or so the engine oil was mixed with additives and abrasives to achieve a smooth surface. At that time it would have been highly advisable to stay in low revs until the initial fluid is changed for regular engine oil.

With modern technology it doesn´t matter that much anymore. More important than this discussion is what AEHaas said: High revs with proper oil temperature only.

 

Been selling "Hi-Po" cars for almost 2 decades now....seen it all....ride 'em hard and put 'em away wet wins the day every time.

Posers who idle around from disco to deli end up with trouble.

The best cars I have driven are the ones that were broken in hard.

 

to answer Korr's question:
And how often are these top fuel motors expected to go 100k+ miles? And how often are they rebuilt?

they are not. The life of the motor is measured in minutes, and they are torn completely apart between rounds. There is no water jackets in those blocks, as it is given up in favor of solid metal to help support the liners. So they do not run long ata time. They are now in excess of 7000HP, which in order to get, trade offs are the name of the game.
Now I will explain the similarities:
1. Bearing surfaces are polished with 1000 grit paper prior to assembly. I doubt that it is possible to get that smooth in a road break in regadless of the RPM and speed.
2. The liner wall finish is a "Plateau Finish" which consists of honing to the last half thou as is normally done, but an extremely fine stone finishes it to size. The result is a finish like glass, with a hint of the coarser stones left to trap oil.
AR put in in perspective. In the Flathed Ford days, putting Bon Ami down the intake was a widely accepted mens os assisting the ring sealing in. Not so today,as rings are far more advanced.
When you think about it, why wear them in? Every .001" increase in bore causes an increase in ring end gap by PI or x 3.1416. All that is accomplished here is more metal in the oil, and a bit more blowby a the ring gap gets wider by just over 3 times the bore increase.
Now imagine the motor set up just as a top fuel but without the extra clearances necessary to accomidate the rapid expansion of the piston when hit with a load of Nitro. Same with the bearings, the same polish that allows them to survive, yet not the wide clearanceds needed to flow more oil in order to cool the inserts.
Take the time to assemble with true tolerances, making sure that all is smoothly turning, with no binding.
The result you will find is a motor that runs strong, lasts a long time, and provides a more efficient power to fuel ratio. To do things this way is not on the price competive replacement market, as time takes time. It is all in what you want out of it in the looooong run.
The initial starting is far more important IMO. Warm it up slow and easy, checking it over to see signs of trouble.and change that filter! six times if you like, as that spin on canister is damn cheap insurance. One spec of grit will score the bearing insert, and they do not heal themselves.
Just my $.02 (before taxes)

 

I would bet even Ferrari doesnt hook up a brand new engine to a dyno and blast it at full rpm right away. Read thier manual on the 308, its certainly doesnt say that. Look at any other type of engine and manufacture and read thier procedures. It doesnt have to be a car engine. Piston rings are piston rings, no matter if they are in a car, a plane, a boat, train, or lawnmower. The only differences are that some rings are chrome, and some engines have chrome or nickel content in the cylinder walls. If the rings are not seated within the first few miles, they probably will never seat properly. Period!
There is another reason for keeping the rpms down as you push your engine at full throttle to higher and higher revs, and its the bearings, whose contact patch under the load needs to be bedded in. No, it probably wont make the difference between it going 100K, or 150K, but like the post about the Corvette, it may make you a stronger engine later HP wise. But if you want to go beat the **** out of it, go ahead. If want your Ferrari in the shop all summer for warrantee work, go ahead. Just dont sell me your car later.
As for what a car can take when its new? I worked for a car rental place at the airport when I was young. I seen these kids taking cars, brand new cars, firing up at 15 below zero up on a parking ramp, and racing the engine all the way down the ramp, and full bore, foot to the floor, all the way to the airport 3 miles away. No BS, I rode with some of the idiots. Car would be hitting 90-100 MPH before a minute after cold start, heat already coming out the dash. Yeah, 7000 mile oil changes with Pennzoil too. No wonder they dump those cars at 15K miles. But they still run "okay", so I guess beating the **** out of a new motor cant hurt it "that" bad.

 

I must agree with most of the posts here, as they are often right on.
I would however wish to clarify my post as a direct response to the question "Break In". The implication I took literally to mean once it is on the road. Fire up is a completely different matter entirely. Gently warming it up, allowing the parts to normal temp, and the initial first few minutes of the motors life are IMO more important than the road time. Varying the RPM to insure the wearing in of various parts is critical. Unfortunately, we dont get to that part with a new car, and as on post mentioned, some times anyone can have a bad day.
That is why I enjoy building my own. I dont have a fellow watching with a stop watch and a clip board over me, and I can take as long as needed to perfect an assembly if I wish.
The positive side is, you dont have to spend weeks worrying over the assembly being right after an 8000RPM blast! It lives, or it doesent.
Then, by all means,
ENJOY THE DRIVE!