Davidls

i had a full b18b1 swap with a custom turbo kit making 240hp on 9 psi. I just recently re-built the motor with 10.5:1 cp pistons and eagle rods. Now to break in the motor would I be able to use the old tune or would i need to get a break in tune. Also how would I drive it for the first 1000 miles or so?

Davidls

bump someone help me out

sleepencivic

talk to your tuner...what i have done in the past with good sucess is throw the stock injectors, map and ecu back in for the break-in and to drive it for the new tune.

0AddictsRacing

^ That is one way to go about doing it. Another way would be to get a base map for your break in, then doing a full dyno tune once you've gone through the first 1k miles. During break in, I always suggest staying under 80mph and not running it through the gears / building boost for the first 800-1k miles.

Basically just take it easy, drive like a grandma, and you'll be fine. Do a little city and a little high way driving.

tofast4uh22

it has been said before that the motor can be broken in on the dyno. all you have to do is put the motor through a couple heat cycles and make sure there is no leaks then bring the car to the dyno for the tune. they can load the dyno at the beginning to help with the seating of the rings.

Davidls

alright thanks guys. I'll just call my tuner and see what he says.

SpoolnG2

Dont do any of that. If the car runs...put it on the trailer and take it directly to the tuner for break in. A motor can be ruined within seconds. Read this article taken directly from LaskeyRacing.com and you might think a little bit different about it and learn something.

Proper Method to Break in your New Engine

One of the most asked questions is how do I break in my new motor? The short answer is that no break-in is necessary. The only thing that is necessary is to seat the rings. All clearances and fitments should be perfect after blueprinting and precision assembly. So how many miles do you have to drive it to seat the rings? The cylinders are round, the rings are round, the bore is freshly honed and therefore your engine should be ready for tuning immediately. They will continue to seat better over a short period of time but you should be ready to go tune right away.

Do I need to drive it 500 miles before I tune it? Absolutely not. How about 50 miles? No. Perhaps the best thing to do is to drive it all the way to your trailer and tow it to a competent tuner. In second position on the “things NOT to do list” is trying to break in an un-tuned engine by driving it. Too lean an air/fuel will begin to heat and distort parts, too rich will wash the oil off the cylinders causing premature wear. What is in first place on the “things NOT to do list”? Boost on an un-tuned motor. Within 2 to 3 seconds the pistons and cylinders can be ruined.
Well I did put in a new base map or I’m just running off the stock Honda computer. Can’t I drive it like that for a few miles? I’m not even boosting. Well what is the base map? Just someone’s idea of what numbers will start your car. Just an educated guess by someone who does not have a clue what components you are running in your set-up. It’s not intended to drive on for any extended period of time. The same with that stock Honda computer. It could be ok but it could also be dangerously wrong.

So what exactly do I do at the first engine start-up? Pull the spark plugs and crank the motor with your starter for a maximum of 30 seconds or until you see the oil pressure gauge begin to register. Re-install the plugs and wires and fire up that candle. While keeping one eye on the oil pressure gauge, use your other eye to scan for fuel leaks. If there are no fuel leaks, look under the motor for any major oil or coolant leaks. If that is ok, run the engine for 5 to 10 minutes while keeping an eye on the temperature and pressure gauges. Keep the rpm’s between 1000-3000. Shut the engine down and double-check everything. You are now ready for tuning.

But my engine was already tuned from my previous set-up. Well, what happened to your previous set-up? Did you melt a stock piston or crack a cylinder? No problem because now you have forged pistons and sleeves? Wrong. Although you now have stronger components that will take more abuse, you are still not right on your air fuel mixture. Get that thing tuned properly ASAP.

OK, I did it my way instead of yours and now I’m burning a lot of oil. What happened? Well basically you scarred up the skirt of the piston, messed up the surface of the cylinder wall and maybe even egg shaped the cylinder. New pistons are tapered smaller on the top to larger at the bottom of the skirt. Your piston to wall clearance is measured at the bottom of the skirt. As the engine warms up to operating temperature, the upper portion of the piston begins to expand slightly. The bottom of the skirt does not expand much. When you boost in a lean condition, the upper part of the piston expands quickly. Since the ring land area is cut smaller than the tapered skirt below it, the first part of the piston that pushes into the cylinder wall is just below the oil ring. Thus you will see the worst scarring on your piston right under the ring lands where the excess heat is the highest.

The more heat that is generated, the harder the piston pushes into the cylinder wall. The uninformed would blame the piston damage on bad piston to wall clearance. Untrue. If that were the problem, the damage would show up at the very bottom of the skirt. What has happened is that you have expanded your piston to the point that it has just ground itself into the cylinder wall. Keep expanding the piston by super heating it and it will push your cylinder egg shaped and maybe even balloon out the cylinder slightly. At the same time this is happening, your ring lands will begin to distort to where they will never seal properly again. Sometimes after doing this, the engine will still run but it will be a smoker. This all happens in a few seconds of high boost with a lean air fuel ratio. Also it can happen from 500 freeway miles of driving where the tune up is off enough to build excess heat at a slower rate, thus doing the same damage over a longer period of time…but the end results are the same. Death to your pistons and cylinder walls.

OK, I’m just going to turn the fuel pressure way up and run extra fat, that way I won’t hurt anything. If you run too rich, you will “wash out” the rings. First, excess fuel will run down the cylinders taking the lubricating oil with it. This promotes direct metal-to-metal contact between the rings and the cylinder wall. This contact does several things. The upper ring begins to wear quickly. The middle ring is actually designed as a tapered oil scraper (it is not used for compression control at all) and the taper will begin to wear down to where it becomes flat rather than angled. When that happens, it can no longer control oil away from the combustion chamber. The last thing that happens is that pretty cross hatch design begins to wear off of the cylinder wall. While most people think that the cross hatch is there to help seat the rings, it also has a secondary purpose. That is to hold microscopic amounts of oil in the grooves to help lubricate ring to cylinder walls. With the walls smooth and no oil control help from the middle ring and a tired upper ring, oil will begin to mix with fuel in the combustion chamber. When this happens, your 93 octane fuel probably hits a value of about 80. Then detonation comes into play and begins to beat holes in the pistons, among other things.

So whom can I blame for this mess? The blind machinist that honed my piston to wall clearance? That poor quality Brand X piston manufacturer? The idiot pro engine builder that assembled my block? My ex-friend that helped me put this all together? Those ignorant engineers that gave me a bad base map with my engine management system? The guy on the internet message board whose buddy knows that it takes at least 1000 miles of break in before you can tune an engine properly? All of the above? Probably none of the above. Go look in a mirror and ask…who started this engine and had no idea what the air fuel ratio was? Who just wanted to jump on it one time to see if it would haul? Who didn’t know that their injectors were at 100% duty cycle at 4000 rpm but they wanted to see how it would run at 6000 rpm? Why it was you. Get that thing tuned right away. You will notice that the more you drive a tuned motor, the stronger it will feel. This is just the rings seating in their final 5-10% as they thank you for tuning first.

keving85

^^^ that's what I did just of last week. Ran engine with my base map just to idle. Kept an eye of afr's. The burped the coolant real quick. Checked for leaks the whole time. Tuner came to pick up car. Drove on. Backed off. He did his thing with ectune then we were off running right away.

Car still feels strong.

Davidls

wow thank you for that article! Im definitely going to trailer it to my tuner when i have the money.

SpoolnG2

No problem, glad it helped. Good luck with your setup and tune.

0AddictsRacing

Very good article.

sparky2pipes

so you should get the oil pressure up, start the car, run for 5-10 mins, check for leaks, trailer the car to your tuner and your ready to drive your motor hard??? or do you still take it easy for a few hundred miles??

cevax

Of all the Break in questions SpoolnG2 has the best answer

I am with Davidls on this one

SpoolnG2

Yes, your ready to drive your motor hard. The rings will continue to seal a little bit more, but otherwise the motor is ready to go.

sparky2pipes

thank mate

attack666

so i was boosted on 9psi on my stock b16, just built my short block.

car is not boosted anymore as i have to register it, so stock exhaust stock everything is back on

i had a safe tune when i was boosted on my s300( low timing/high fuel), with no problems i just decided to built my motor.

can i drive it with the same tune?