I found this site on the web and wanted to share it with you guys. I am about to fire up my newly rebuilt(for the 3 rd time) 383. I am scared to death that I wont get the rings sealed the correct way after it is started and this site just confuses me even more.

Do I run it hard after its warmed up and the timing is checked or do I take it easy?
Break In Secrets--How To Break In New Motorcycle and Car Engines For More Power

 

if what hes saying is true, and it seems to be id try it But the choice is yours

Make sure u follow what hes saying methodicly Just in case

 

I dont want to make the choice if Im not confidnt in it. Ive had this engine rebuilt 3 times already and I dont want to do it again becuz the rings didnt seal

 

If I remember correctly, you washed the rings out of your last motor because you were dumping too much fuel. I don't remember if it was because of the ECU not calibrated for the injectors or what, but you need to make sure that gets straightened out.

When you fire the motor for the first time it's not going to be tuned for optimum performance. You just need to get the timing and fuel close. Set the timing to 32-34* total and make sure it's not dumping a ton of fuel, i.e. set the fuel pressure and make sure the computer is set for the proper injectors. Use a non-detergent oil and try to get ahold of a filter pre-screen. Moroso makes them and they're about $5. They make it easy to see any metal that's being created in the motor. Start it up and keep the RPM's up (just don't let it idle) and run it for 5-10 minutes. Shut it off, check for leaks, check the fluid levels. If all is good, then start it back up and run it at a fast idle for another 10-15 minutes. Get a total of 20-30 minutes of run time on it then let it sit and heat soak overnight. Come out the next day and drain the oil. Inspect it for any metal or fuel. Pull the filter and look at the screenl. If it's all clean, put a good grade oil in it (whatever you plan to run) and drive it around with a light load for a few minutes. Do a compression and leakdown test to make sure the cylinders are sealed up good. That's it. Very easy.that's how we break in all motors on our engine dyno. Now you can start tuning it. Put a couple more degrees of timing in it and see what it likes. Play with the fuel pressures. Best thing is to get it on a chassis dyno but not everyone has that luxury. Good luck

 

Dialed In, thanks for that very informative info. I have 2 tunes for my car that the dyno tuner set up for me the last time this engine was running so the tune is pretty much dead on. I have a tune that is set up max HP and I have another that is setup for emssions/fual milage. The air/fuel ratio in this tune is 14.7:1 across the entire table. I am running a FAST ECU. The stock computer is in the trashcan. Im not sure if I should start off running the safer tune at first. I have been thinking about it and it may be what I will end up doing for the first few thousand miles. Once everything looks good, I will switch to the max hp tune which is kinda rich. As for the timing, its already in the tune, all I have to do is make sure I have the dizzy in right. My timing is set at 6 degrees on the balancer. this is how FAST says to set it up. all the changes are made right in the calibration. so, once the dizzy drops in, which way should I rotate it a little to get close to 6 degrees so the engine will fire right up?
Getting back to the break in procedure, first, what type of nondetergant oil do you use? All the ND oil at autozone says not to be used on newly rebuilt engines or hydraulic roller lifters. also, what exact RPMs should I be at once this fires up?

 

Not a lot different from the GM crate engine recommended procedure.

https://www.thirdgen.org/forums/faq-...procedure.html

In 1973, a Honda mechanic told me the "right" way to break in an engine was to start it up and hold the throttle wide open until the exhaust pipes changed color. He didn't do that with customer bikes unless they said it was okay, but that's what he did with his own race bikes.

(Can anyone see the piston pics on Bottled's link?)

 

In my opinain, the way ive fired up all my engines is start it up, get timing and fuel somewhat in the green, and hold up up to 2000 RPM to get the cam broken in. When it reaches op temp, shut it down check for leaks and proper oil levels. Then start it up again and slowly go from 1000 to 2500 RPM to seat the rings. Then change the oil, and drive it normally for 500 miles.

 

Forget brake in, just side step the clutch a 6 grand, and leave your foot in it until the top of 4th!


Hey look at me--->

 

I break in ALL my motors that way, and have never had a problem with it. Remember, if you have a non-roller cam, you have to break it in first befor you can seat the rings like described in teh link.

 

I broke in the 350 this way back in '03, no mechanical failures. Well ok just one that was my fault. Rocker got loose and a pushrod ended up being banged up last year.

 

Most all race motors get the "unload from trailer and go racing" for a break in, with all the modern day parts and good shop builds many of these race engines (drag engines anyways which I consider just beefed up street motors since they're not holding 7-9000 rpm for 20 minutes straight) when they are torn down at seasons end, they check bearings and tolerances, more often than not they are bolted right back together with same parts since there's nothing wrong with them.

First motor I raced with I did the **** break in procedure, when I finally pulled it and did a tear down to inspect before selling everything looked hunky dory. This past motor I did the inital fire up, took it out and hammered the ppizz out of it from day one. over 1800 passes down the strip and 5-6K street miles everything looked as good as the day it was put together (save the end of the crank that snapped off) all rod/mains still had the factory teflon coatings installed, absolutely no ridges in any cylinders, pistons looked brand spankin new yet with no carbon deposits on them...truely amazing and a testiment to having a real shop build my junk and why I refuse to try my own luck doing it...costs to much $$ and time to screw it up.

AFter everything checks out...drive it like you stole it and have no fears. If it's going to blow it will blow, there is absolutely nothing you can do to stop it, all your doing by babying it is prolonging the inevitable. Sounds soo far off base from everything you've heard growing up about break in's, but the harder the better.

 

the only thing i'd like to mention, is to make sure your fueling is set up right, before you hammer on it. The only reason I didn't drive mine hard, right after cam break in, was because I was sure the carb wasn't set up right, and driving it lean and hard isn't a good thing! Once you've got the carb set up (or FI in your case), then go nuts!

 

I'm a firm believe of beating on it. I read that link a long time ago when i started to get my motor almost done. Then IHI said something similar...babying it won't keep it from blowing.


I just hope I havn't washed down my walls too...

 

about 6 years ago i helped my cousin build his 350 for his pickup. as soon as we broke the cam in, and changed the oil he pulled out of the shop onto main street and hammered the dog s@#$ out of it and drove it hard all evening! that engine today doesn't smoke or have any kind of noise internally and still runs great! just kinda scary to do a "procedure" like this when you have spent alot of time and money!!