pskel350

i have a brand new ls6 forged engine that i will be firing up soon. how do i break in the engine the right way? just like the old sbc at 2000rpm for 25 min? or dont i need to do that since its a roller cam?

i've been hearing mixed opinions, some say dont rev it at all until it reaches operating temp. others say set it at 2000rpm right away to start to seat the rings....

Air_Adam

It is a roller cam, so the cam break-in technique for the old SBC doesnt really apply here. Just like the roller small blocks, just running at idle speed should be fine for the camshaft.

Also, IIRC, the engine has to be under load (ie. driving around) to seat the rings properly. Just running the engine with no load won't do it.

I don't know anything else about engine break-in though, since I have never actually done it myself.

pskel350

see thats why im getting confused, some people say just let it idle for 30 minutes then drive it, and some people say you must run it at a high idle like the old sbc to "start" to seat the rings. i think im going to just let it idle.....

Jgolden314

call livernois and ask them, should work.

ME Leigh

Your supposed to run the engine upto pretty high rpms with some actual load on the engine to properly seat the rings. Idle it for 30secs run up tp 3000 then 1/2 throttle to 5000-6000 a couple of times. Then back down to 3000 and repeat 10 times or so...

This procedure is the best for properly seating the rings!

vejatabul

http://www.mototuneusa.com/break_in_secrets.htm

Klortho

The Haynes manual actually says to go down a road from 30-50mph about 12-15 times and that will load the rings and let them seat, then drive normally, don't pamper or abuse it for about 500 miles change the oil then drive it normally again, not really abusing it until about 2000 miles and consider it broke in.

Kandied91z

iTrader: (7)

exactly, don't drive like a grandma or an a hole.. just drive it. wait until it has some mileage before you take it to the track or try to impress the girlfriend and you'll be fine.

pskel350

sounds good, guess we'll see. never had a problem breaking in new motors yet, but never played with the lsx motors before either

five7kid

iTrader: (14)

We're using ill-defined terms here. "Break-in" typically is used for the process of seating the rings. There is also cam "break-in", or sometimes called "run-in", that only applies to flat tappet type lifters - that's the 2000-2500 RPM no-load for 25-30 minutes thing.

What it takes to "seat" the rings has been a topic of conversation (read: disagreement) for decades. Over 3 decades ago I was at a Honda dealership getting parts for my bike when the topic came up - their ace mechanic was also a racer, and his reported break-in method whether new or rebuilt was to start the engine, hold the throttle wide open until the pipes started turning red, then shut it down. His bikes were faster than anyone elses, they said.

This used to be on the GM Goodwrench site; it isn't anymore, for some reason:

Start-up instructions:
1. Always put safety first. If your car is on the ground, be sure the emergency brake is set, the wheels are chocked, and the transmission cannot fall into gear.
2. Be sure to check the engine's oil level and prime the oil system.
3. Run the engine between 2,000 and 2,500 RPMs, with no-load on the engine for the first 30 minutes.
4. Adjust the distributor timing roughly by hand for a quick start-up and the smoothest idle possible.
5. Adjust the carburetor settings, if necessary.
6. After the engine has been running for 30 minutes, set the ignition timing (see install ignition section for timing specifications).
7. Drive the vehicle with varying speeds and loads on the engine for the first 30 miles. Be sure not to use a lot of throttle or high RPMs.
8. Run five or six medium-throttle accelerations to about 5,000 RPMs (55 to 60 MPH), then let off in gear and coast back down to 20 MPH.
9. Run a couple hard-throttle accelerations up to about 5000 RPMs (55 to 60 MPH), then let off in gear and coast back down to 20 MPH.
10. Change the oil and filter with 10W30SG oil and PF1218 ACDelco oil filter (PN 251605610).
11. Drive the next 500 miles normally, without high RPMs (below 5,000 RPM), hard use, or extended periods of high loading.
12. Change the oil and oil filter again.
13. Your engine is now ready for many happy cruising miles.

Of course the oil recommendation is out-of-date. And, the cam break-in, Step 3, isn't required with roller lifters.

MrDude_1

this is going to sound wierd, and diffrent then all the other advice given.


if its stock LS6, just drive it. modern OE rings dont need anything special to seat. the cam is a roller.


if its cammed, just break in the valve springs. they're about the only component in there that needs special break in for long life.

five7kid

iTrader: (14)

I assumed from the "forged" part that we were talking about a "rebuilt" engine.

Oh, also finally found this https://www.thirdgen.org/techbb2/sho...hreadid=206726 (I knew it was there, just wasn't looking for the right thing).

MrDude_1

you know, they do make OE forged bottom ends for the genIIIs... and if its a REAL LS6 and not just the LS6 block, then its factory forged.....

five7kid

iTrader: (14)

If it's a new factory crate engine:

Ever taken a factory tour and watched them drive the new cars off the end of the assembly line?


When firing up my rebuilt ZZ(4) shortblock:

I intend to follow the GM instructions above (w/o the cam run-in part).

FWIW, my brother recently installed a rebuilt crate 350 (L98-type) longblock. He said the way the engine acted before and after the above process was performed was a pleasant surprise.

However, a new factory crate off the same assembly line as production cars - perhaps a completely different ballgame.