Beat the **** out of it, or go easy for awhile? I've heard both ways, what do you guys think is the proper way to break in a new LS based motor?

 

I'd put a good 500 gentle breakin miles. Vary RPM, no extended WOT, etc before putting the full tune on it. That's what I did in my forged LS6 setup, maybe NA is different, but I didn't want to risk damaging a motor that took over two months to build.

So what did you end up going with ??

 

Fill it with Rotella oil - run 300 miles. Change again to Rotella for another 700. Change to your favorite synthetic. Run easy for the first couple hundred and your good. Rotella has ZDDP in it which is the anti-scuff agent that EPA made them take out of street motor oil. Rotella is a diesel oil I broke my 402 in this way and it doesn't smoke of use any oil at all.

My $.02

 

I haven't, I've narrowed down a few choices but I keep adding more!

 

I'd Go easy on it for a while, and vary the rpms, and change the oil every so often.

 

Never heard of the Rotella... might be pretty good. I like to break in with a non-synthetic, aka dino oil. Change at 600 miles, and again at 1500, the second time with syn.

 

I knew that SAM's club had Rotella so I asked the wife to pick up a gallon or 2. She brought home a case (6 gallons) of 15/40wt. Looks like I'm set for a while.

I should start assembly sometime next week. I'm expecting my Thunder Racing Cam any day.

I'm going to run it up and down 95 for about the 1st 50 miles, varying the rpm.

Bob K.

 

There are basically two opinions on breaking in a newly build engine - drive it like you stole it, or drive it like it's your money. I'm in the latter camp.

Here's what I did on my last build, a turbo'd Miata (thus the rev differences). I'd reduce the rpms by 1000 for a V8. I've done variations of this on every engine I've built in the last 40 years, and they were all strong, and none ever failed.

(copied from a website post):
Let the engine idle for 10 min then idle at 2000 rpm for 10 min. turn car off and let it settle for about 5-10 min. This is primarily for the cam lobes. If your cam isn't new, just warm the engine up and move on.

0-200 miles.
Try to keep the highest rpm under 3000 rpm. Every 15-20 miles,spin the engine to 4500 rpm in first and sometimes in second gear.

200-400 miles.
Try to keep the revs limited to 3500 rpm. Raise the revs rpm to 5500 with the same frequency as above.

400-600 miles.
Go to 4000 rpm for driving limit. Raise the revs to 6000 - 6500 rpm and include 3rd gear pulls, same frequency as above.

600-800 miles.
4500 rpm driving limit. rev it to 7000 rpm and include partial 4th gear pulls.

800-1K miles.
5000 rpm limit with revs to 7500 with some pulls all the way through 4th and partial fifth gear pulls.

Use non synthetic oil for the first 500 miles, change oil with non synthetic, (it is not necessary to change the filter) then once you meet the 1000 mile mark go ahead and change it with a full synthetic and a new oil filter.

 

I had my new LS1 installed in october. It was started with Mobile 1 and will stay that way. Mech. at dealer said tke it a little ease first 500 miles then Drive it like always.

Keep in mind it's a brand new factory crate motor and warrantied fro 5 years 100k miles.

Good luck.

 

What do you guys think about this....


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

 

I also ran a 750 mile cycle of Valvoline Racing (Not for Street Use) which also has ZDDP in it. There are too many 402's out there that smoke and use oil because they were worn out in the first 100 miles. I'm going to go with a 10-40 synthetic next.