new engine break in
 

My car is going into the shop finally next week for a fresh LT1! what a releif!! i am wondering what the proper technique is to break in this engine, i know the basics like, dont lug it, varry speeds, dont go full throttle, but are there more specifics for this engine as in cretin RPM ranges to stay in/ avoid? any input would be appreciated.

Engine Break In
 

My engine builder told me that when I got ready to fire mine off get it up to temp. make sure everything is working properly run it long enough ot the get the rings seated correctly. Then beat the living dog piss out of it :jest: . Worked great. After 7,000 miles of streetracing :drive: and a overall beating I pulled the heads off to put some afr's on and the engine looked excellent. Never runs hot and doesn't use any oil between oil changes.

there is so much controversy on this one...im getting ready to take my 355 out of the shop and im gonna do the 20 min warm up..change the oil..drive it 100 miles change the oil while driving it kinda medium..not babying it but not wide open....then change oil at 1500 and then i will be set to go.

Everyone has different break in process that they follow. I also am puting a fresh motor in my car, new bearings, honed, and re ringed. I have been doing alot of research, and hear is what I plan to do. Get the motor up to operating temp, check for leaks, retighten anything. Change oil after first warm up, start the car back up and head straight for the highway. Bring the car up to about 50mph, and hammer it up to 100+, and repeat a few more times. The rings seat from high cylinder pressures. Taking it easy for an extended period of time will no properly seat the rings. But im sure there are plenty of people that would say to take it easy for 3,000-5,000mi. I dont buy it, the rings should be seated as soon as possible.

Get the engine up to temp. Drive the car at a variable rpm with a load on it at all times. Only things to break in are the rings. Use the engine for acceleration and braking. Dont be scared to beat on it. Breaking in an engine this way will keep the rings loaded and will seat them properly.

heres what they are going to do to mine. put break in oil in it, run it for 20-30 mins. change oil, run for 250 miles on the dyno. change oil, dyno tune, then go balls out.

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

Read this, this is what im going to try next.

250mi on the dyno....

sweet

Just felt like commenting as well.... The mechanic that helped me with my new engine said that I need to seat the rings as well... We started it up and let it idle to temp 3 or 4 times and then he said to take it around town a few times being easy on it but dont dirve like grandma, just make sure it feels right. After I did that he said drive it like you stole it... And change the oil at 500miles and then every 3000miles after that. His comments were that if the engine is any good it should not have a problem and that if there was, its better to know right away while the warranty is good. So far there's no problems other than having to tighten down the rockers a bit.

same here i built a 327 street motor for my 80z and went burnning out of the drive way and spun a rod bearing no idea how but did so we replace the parts and did it again and till the day i took it out to put the smog motor back in it ran like a somabitch so its all up to the person and how they want to do it

Same here, I did what Motoman recommends..

sounds like a few mixed oppinions, but your input will help, thanks.

I am also putting a fresh moto in my car lol

1. Warm her up to operating temp
2. Check for leaks
3. Run her up through the gears shifting at 4K each time
4. Allow the car to slow itsself down ( ima engine brake it to all the car high revs/pressure )
5. Do this a few times ( 3-4 )
6. Replace the oil and good to go


How does that sound?

i went the very "umm" long way and did it as people have allways told me to do...

started it up with valvecovers off let it warm up and make sure oils coming into the heads...turn car off. slap valvecovers back on..change oil..drive for another 100 miles easy...change oil again....drive another 400 medium wise not going past around 4k and then change the oil and change to synthetic from the straight 30 weight oil for break in and then balls out

I went a long time compared to you guys..changed the Oil after the first 500mi to a Synthetic Blend, didn't bring it over 3000RPM for the first 1000mi, changed it again at 1500mi, and then ran it up the RPM's little by little eventually until Redline. Now I am at 4000mi, and doin an Oil Change soon as it gets back together.

Oh.. I was also told you must do the break-in with regular oil! Forgot to mention that. Something about the synthetic affecting the rings seating right. Any thoughts on that? I still run regular oil since I hear synthetic ends up finding a way out (leaks).

If you hear that about Synthetic, I can back that one. I have Oil leaking in some places that I have never had a problem with. The Oil Pump is strong, and it runs higher than normal RPMs compared to most Engines.

Crank it up. Bring it up to temperature. Drive it down the road to make sure that all three gears are working. Load it in the trailer. Unload and go thru tech. Drive it to the staging lanes.....

Here is whats Pace Perfromances told me to do:

Be sure to check the oil level in the engine and prime the oil system with an engine priming tool! This is the most important step! Your crate engine has most likely sat for a while and most of it's lubrication has drained back to the pan!


Quality 10W-30 or 10W-40 Oil is recommended for GM's Performance Crate Engines. Most Stock Factory replacement engines use either 5W-30 or 10W-30 oil. If you plan on running synthetic oils, we recommend that a new engine is first broken in with regular mineral type engine oil.


Remember that the cooling system on a fresh engine swap will have a lot of trapped air, which will lead to wild temperature gauge readings and possible water pump cavitation (water pump not moving coolant due to trapped air) To help avoid trapped air in the cooling system, try to fill the cooling system up with a 50/50 mix of quality coolant and water a few hours before you plan on starting the engine. Leave the radiator cap off during this time. This will tend to help purge a fair amount of trapped air before you start the engine. Specialty fill funnels can also be purchased from Listle tools and Snap-On dealers that help alleviate this problem. Also helpful during break-in is to use a Lever-Vent type radiator cap on your radiator in so that you can manually purge trapped air while engine is running- (use extreme caution to avoid being burned by hot coolant) Your normal cap can then be re-installed after engine cools off.

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 RPM.

Run five or six medium-throttle accelerations to about 3000 RPM (40 to 50 MPH), then letting off in gear and coasting back down to 20 MPH.

Run a couple hard throttle accelerations up to about 5000 RPM (55 to 60 MPH), then letting off in gear and coasting back down to 20 MPH.

Let engine cool and change the oil and filter and check coolant level, top off if necessary.

Drive the next 500 miles normally, without high RPM's (below 5000 RPM), hard use, or extended periods of high loading.

Change the oil and oil filter again.- Keep an eye on oil level during the first thousand or so miles.

Your engine is now ready for many happy cruising miles!