irocz383

Whats the best way to break in a new motor? I've heard of letting it idle for 20 minutes to let the valve train set in. Then let it rev at about 2000 rpm to further set the valve train. Then of course drive it around the city like an old lady for a few hundred km. Then bring it slowly up to freeway speeds for a while again. Then on to the 5000 km break in period to let all the bearings set and the rings.

Does this sound about right or is there more I should or shouldn't do?

Thanks, Ken

graham

here's what I did for the last 5 or so. None of which seem to be adversely affected by this method.

I only let it idle long enough to listen for major knocking, loose rocker arms, vacum leaks, and to correct the idle (on the carb motors).

This usually takes about 30seconds then take it up to 2250 for a minute. Then go up to 3000rpm for two minutes. After that SLOWLY raise the motor from about 2000rpm to ~3000rpm for about 2 more minutes. Shut it down and let it cool completely off. Crank it back up and drive it kinda soft. I always get on the highway and go from either 30-50mph or 40-60mph about ten times. I always find a gear that I can slowly accelerate the engine from 2000 to ~ 3500rpms and let it slow itself down, and then repeat the operation about ten times. After that drive it kinda soft for about 300 more miles, change the oil (while the oil is warm) and give her hell!

Theres almost as many ways to break in an engine as there are parts manufacturers for small block Chevys so make a mosh of what people tell you here and you should be fine.

arnie

The worst thing you can do is let it idle. In the past, with non roller cams, you'd bring it up to 2-2500 quick and hold for 'bout 20 minutes. Now with roller cams, it is mute.

Now the breakin is with ring seating formost. Babying an engine for breakin is fine is you are building a 'tight' engine for mail carriers and old people. Babying an engine for breakin has little merit.

If you are really a fanatic, the best way to break in an engine, is on a engine dyno, where you can put a controlled load on it. In lieu of that luxury, run it hard, climbing the rpm ladder, with sudden drop off of the throttle in between, for cylinder wall lube. I said run it hard, ie full throttle. I did not say wind the sh*t out of it. IOW, you can run it hard without running redline. Change the (dyno) oil within 500 miles, and put in a good synthetic. You can easily break in an engine correctly in 500 miles. It should take less than that. Better yet, you can do it within a day.

Soma07

On a similar note has anyone tried GM's engine break-in oil additive?

I've seen it in the SDPC catalog and I was wondering if it had any merit.

Thanks!

arnie

Hopefully, the othe pro engine guys will chime in also, but I'll give my $.03 worth. If you are referring to the EOS (super) then yes, good stuff. I used it as assembly lube primarily. Years ago, B4 it was (super), one guy would just throw it in a box, as it came along for the ride with new gm engines. He didn't use it, till he realized it was good stuff. LOL Now days, you have more brands of assembly lube available to choose from. If you are talking something else, I'm clueless.

Soma07

arnie:

Yep, thats the stuff! Although its not marketed as assembly lube but rather as an oil additive to be used during break-in. But if it works as assembly lube then great, its three times cheaper than the Redline assembly lube shown on the same page

Thanks!

arnie

Don't be puttin' words in my mouth. i did say it is good stuff. However, I added there are other choices out there. EOS has been around for about 35 years. To say the EOS is superior to lubes that have been around just a few years could easily be considered a false statement.

Soma07

Gotcha, I read your last post too quickly and I didnt realize you said "used" as in past tense.

lt4 fd

Would break in be any different for a solid roller or as long as its a roller its all the same?

irocz383

Thanks guys!

So I guess I can just drive it like I drive my 305 then. Would you guys recomend using that oil additive?

How about initial start-up. I know I'll have to prime the block but how about after that. Should I just climb the RPMS, slow at first just to make sure the valve train is set in place?

aggiez28; If I can't post this here were does it belong. After all this isn't your average 350 build up. Its a fully forged 383 built for nitrous. The last thing I want to do is screw up thousands of dollars just cause I didn't break it in properly.

arnie

Jason, felt I should add this as well. EOS was a very good product 35 years ago, it is still a good product today. However, you ask 5 engine builders what assembly lube they use, and you could very well get 5 different answers. Fact is, there is more than 1 good/acceptable product available. An engine builder who decides to try a certain product, for whatever reason, finds it works well for him, so he sticks with it on the next engine. If a product performs well, you figure why switch, and it will give you confidence to use it again. This gives you peace of mind during assembly. When a person has thousands in an engine, what is an extra $10 if it gives you peace of mind. Does that mean it is the best product? Hell no. Is there a need for a best definition? Or just one that will meet the requirements set?

With that being said, EOS like I mentioned, was included with new engines built by GM. It also came with their cams. That btw, was it's primary use, to prelube the flat tappet cam prior to initial startup. That leads to the next statement.

Two things to be concerned with, upon initial startup. One is cam breakin. The other is ring seating. With the advent of the oem roller, the first has become mute. That has changed how the engine is initially run. No longer is it necessary to hold a steady 2000+ rpm for x number of minutes. As far as solid/hydralic roller is concerned, my position is that of spring pressure concern, not of the type of roller. That leaves the other concern, ring seating. I personally prefer to preheat the coolant, by whatever means available. Once started, valvetrain checked, and gauges/temperatures have stabilized, I'll run it through the cycling process, climbing the rpm ladder. The sooner, the better. BTW, I did not address ignition and fuel requirements. These are my personal views.

irocz383

Once the motor is broken in I'm getting the Nozle kit from NOS.

I'll start off with 100 just to get used to it. My original plans were to only go to a 200 shot but I know it will never be enough. The kit can go up to 300 or 350. I can't remeber exactly.

I don't wan to spray on a fresh motor, thats why I'm not going to buy it until I need it. I just know if its in I won't be able to keep myself from using it.

Injuneer

Not sure why not. When the assembly was finished on mine, it went on the engine dyno under low load for about an hour, the oil was changed, bolt torques checked, and then run for approx 24 tuning pullls, ranging from 500hp N/A to almost 800hp on N2O. Then it went in the car, with several more chassis dyno pulls to verify everything was done correctly and there were no unexpected losses from the rest of the install. When it was all done, it was ready for street and track.......