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Engine Break-in
It is critical that your Cosworth engine is not started with an excessively rich fuel mixture.
An excessively rich mixture will wash away the oil in the cylinders and the rings can potentially never break-in
causing excessive oil consumption, crankcase blow-by and lower power output. This damage is permanent.

If the engine will be broken in by driving the car, we recommend you keep the engine speed below 4000 rpm.
Drive the vehicle at various loads, speeds, and throttle positions while keeping engine speeds below 4000 rpm for approximately 1000 miles or 1660 kilometers.
The longer the engine is broken in, the better your results will be.

If breaking your engine in on an engine dynamometer, follow the break in procedure detailed below.
You can use the guideline for a chassis dynamometer as well, but load readings will differ.
If using a chassis dynamometer make sure to keep water temperatures below 95 degrees Celsius and oil temperatures below 110 degrees Celsius.

• Run at 2000rpm @ 50-60 lbf-ft. load for 20 minutes
• Run at 3500rpm @ 90-100 lbf-ft. load for 20 minutes
• Run at 4250rpm @ 100-110 lbf-ft. load for 10 minutes
• Run at 4250rpm @ 125-135 lbf-ft. load for 5 minutes
• Run at 5500rpm @ 125-135 lbf-ft. load for 5 minutes
• Run at 5700 rpm @ WOT for 2 minutes (not to exceed 300 lbf-ft.)

During the final break-in stage, the boost should be limited so as not to exceed 350 lbf-ft. of torque.

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After about a 10-minute warm-up at 2,500 rpm or so, this roller-cammed engine was declared ready to do some serious power pulls.

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It was lunchtime, I took the opportunity to pull the plugs to see what the mixture spread looked like.
I also looked at the bores while doing this, and they did not look good! There were fine scores in every cylinder and deeper scores in some.
In less than an hour's running, this engine had completely bypassed the broken-in phase of its life and had gone straight to the wearing or worn-out phase.
This meant its competitive life on the track would be shorter and less effective and a new high-dollar engine, or at least a rebuild, would be needed that much sooner.
Had the need for a break-in been more clearly understood, this engine would have made more power and lasted longer.

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I have seen a number of really good engines that have had the edge taken off their potential power because the necessity for an adequately extensive break-in was not appreciated.

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After all, everything will smooth out as the engine runs. The key is the break-in procedure.
When the newly machined parts rub over each other, there is microscopic welding and tearing.
Each time a weld is torn, it creates another microscopic rough patch or surface wound that also needs to be broken in.
In essence, the mating parts need to either very finely machine their mating counterpart or knock down the microscopic spikes to smooth the surface.
If too much microwelding occurs too quickly, the surface finish is worn out rather than improved.
We need to avoid too much speed and load to prevent excess microwelding and surface tearing.

Offtopic - Lesen auf eigene Gefahr

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BREAKING IN THE ENGINE

First 300 miles should be driven with NO BOOST AND NO MORE THAN 4500RPMs. You want to do as much city driving as possible (lots of stop and go driving). As you are coming to a stop or slowing down, you should be downshifting and letting the engine do some of the braking work. If you do accidentally see some boost, that’s ok but try not to use any boost if possible.

New forged piston engines will use some oil during run-in. You want to keep an eye on your fluid levels at all times during the break-in process. Again, you will typically use some oil during the break-in process.

New forged piston engines also make more noise than stock engines do, so do not be surprised to hear more sounds coming from your engine. The sounds should be light tapping noises and start to settle as engine temp builds. If at anytime you hear anything that sounds unusually loud or gets louder as revs increase, do not run the engine until you can deduct what the sound is.

After 300 miles, change the oil/filter. Take a look at your oil. It will look dirty and probably have a swirl effect to it. That is the moly that is contained in the assembly lube. You should not have any metal flakes, chunks, etc come out with the oil. If you do, contact us ASAP and do not restart the engine. If the oil smells like fuel, that is a good indication you are over-fueling the engine and you need to do some more tuning to correct this. If you want, you can cut apart the filter to inspect for metal in the oil.

Install new oil/filter and recheck all fluids again. Now you can start running some boost and revving the engine a little higher.

Next 1200-1500 miles can be driven with boost pressures up to 10-12psi. This is usually wastegate set pressures for most turbos and external wastegates unless otherwise altered. Try to keep boost at no more than 10-12psi.

For every 250 miles you drive, you can increase the engine revs by 250. So at 550 total new miles you can now rev the engine to 4750 RPMs. You want to follow these building steps up to your desired/new engine limited redline. I suggest you set the rev limit at 7000rpms at first.

As with the first 300 miles, you want to keep aware of your air/fuel ratios and make adjustments as needed.

After a total of 1500-1700 new engine miles, you should change the oil/filter again and can now have the car dyno-tuned if desired. Do not exceed any limits set for the new engine like RPMs and boost. The blocks we offer do not have a hp limit assigned to them, they only have rpm and boost limits. You must stay within those rpm and boost limits at all times. Enjoy your new engine and thank you for your business!

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Nahezu jeder Mietwagen, den ich fahren durfte, ging gefühlt wie Zau.

Zitat von »josedan03«

Mist bin nach Handbuch vorgegangen, dann kann ich die Karre jetzt wohl ohne "Drittenkörper" wegschmeißen oder

Zitat von »Schall & Rauch«

Habe zwei Subaru Zwoo-Fünfer nach Vorschrift eingefahren - Ölverbrauch von Anfang an.
Mehrere Motorräder und weitere PKW's verschiedener Hersteller FULL-PULL eingefahren.... Null Ölverbrauch und über Leistungsmangel kann und konnte ich nicht klagen.

Kann natürlich am Subaru Zwoo-Fünfer liegen.

Zitat von »patGT«

Interessanter Artikel, kommt mir aber bekannt vor. Hatten wir das schon mal hier?
Sollte es wirklich so sein, dass die ersten 20-30 km am wichtigsten sind, hätten die meisten Neuwagen schon verloren, insbesondere diejenigen, die mit dem Schiff kommen (wie unsere...). Wenn sie am Ende beim Händler zur Auslieferung an den Kunden bereits stehen, haben die meisten ja schon ein paar Kilometer runter. Da bliebe von der "Jungfräulichkeit" also nicht mehr viel übrig.

Wie auch immer, seit ich Fahrzeuge auch, sagen wir "progressiver", einfahre (nicht nach Büchlein, sondern sportlicher und schnell steigernd), bilde ich mir ein, dass die besser gehen.
Wenn man zu zahm einfährt, kommt die Karre nicht aus den Puschen, das ist jedenfalls auch meine Erfahrung.