Proper Break in LT1 355..
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From: Tomball (H-Town), TX
Proper Break in LT1 355.. Completey Rebuilt Engine, and Transmission (also rearend) as listed in sig never drove a mile... everyone says let it heat up to around 160 (remember it has a meizere electric waterpump and 160 stat) and that break in usualy is over technically by 30-40 miles of easy driving letting it settle, and that at 50 miles to change the filter/oil.. and for the next 100 miles keep it under 50% throttle then after that go wild but not extreme.. that has to be broke in like i will usualy drive it.. hard hard hard?? 
please people who have done this the right way beforel ooking for some insight this project has run me $10,000 so far i dont need to **** it up
im totally outta money
please people who have done this the right way beforel ooking for some insight this project has run me $10,000 so far i dont need to **** it up
im totally outta money Guest
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Have been told you should NOT use synthetic oil duringin break in. Its helps the cam break in and all I guess. Most guys I have known have driven to 75-100 miles easy then changed the oil.
If it was me I would let it idle and heat up, cool down,at least once to check for leaks and watch the oil pressure. I know a guy that checked for leaks first and trashed a motor. I know a lot of guys say to hold the car at like 2000RPM for so many minutes to help break the cam in.
Take it for a spin, tighten the headers bolts to aviod leaking. Drive it a good 75-100 miles easy, change the oil, next 20 miles go 50-75% throttle, after that have fun.
WATCH YOUR OIL PRESSURE!!!!!!!!!!!
If it was me I would let it idle and heat up, cool down,at least once to check for leaks and watch the oil pressure. I know a guy that checked for leaks first and trashed a motor. I know a lot of guys say to hold the car at like 2000RPM for so many minutes to help break the cam in.
Take it for a spin, tighten the headers bolts to aviod leaking. Drive it a good 75-100 miles easy, change the oil, next 20 miles go 50-75% throttle, after that have fun.
WATCH YOUR OIL PRESSURE!!!!!!!!!!!
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From: Tomball (H-Town), TX
Originally Posted by JUICED96Z
Have been told you should NOT use synthetic oil duringin break in. Its helps the cam break in and all I guess. Most guys I have known have driven to 75-100 miles easy then changed the oil.
If it was me I would let it idle and heat up, cool down,at least once to check for leaks and watch the oil pressure. I know a guy that checked for leaks first and trashed a motor. I know a lot of guys say to hold the car at like 2000RPM for so many minutes to help break the cam in.
Take it for a spin, tighten the headers bolts to aviod leaking. Drive it a good 75-100 miles easy, change the oil, next 20 miles go 50-75% throttle, after that have fun.
WATCH YOUR OIL PRESSURE!!!!!!!!!!!
If it was me I would let it idle and heat up, cool down,at least once to check for leaks and watch the oil pressure. I know a guy that checked for leaks first and trashed a motor. I know a lot of guys say to hold the car at like 2000RPM for so many minutes to help break the cam in.
Take it for a spin, tighten the headers bolts to aviod leaking. Drive it a good 75-100 miles easy, change the oil, next 20 miles go 50-75% throttle, after that have fun.
WATCH YOUR OIL PRESSURE!!!!!!!!!!!
btw on the oil pressure we replaced everything even oil pump/reciever its a whole new engine
but ill still be watching it 
Last edited by Gun5; Jun 23, 2006 at 01:40 AM.
Yes use a regular crude oil for break in. Change it @ 50-100 miles, then again in another 100 miles...
Reason being, when things seat properly there will be fine shavings in the oil system, and you wanna remove them as much as you can, so I would recommend a Filter Magnet, and a Magnetic Drain Plug to keep them held still as they pass through the system. As for not using synthetic, it's too slick and wont let everything set and break in properly. Use crude based oil for the first 1500-3000 miles, then switch over to Synthetic if you plan on running synthetic. Use a quality motor oil for break in, just cuz you have to do 2-3 oil changes don't think you can get by with using cheap stuff since it's only gonna be in there for so long. Break in is probably the most critical life of an engine...Good luck!!
Reason being, when things seat properly there will be fine shavings in the oil system, and you wanna remove them as much as you can, so I would recommend a Filter Magnet, and a Magnetic Drain Plug to keep them held still as they pass through the system. As for not using synthetic, it's too slick and wont let everything set and break in properly. Use crude based oil for the first 1500-3000 miles, then switch over to Synthetic if you plan on running synthetic. Use a quality motor oil for break in, just cuz you have to do 2-3 oil changes don't think you can get by with using cheap stuff since it's only gonna be in there for so long. Break in is probably the most critical life of an engine...Good luck!!
Originally Posted by Z28&WS6
i have always heard do not get on the highway to break the motor in. you want to vary the engine speed a pretty good bit.
Varied speed is good, but a smooth steady RPM for a decent length of time will allow the rings to properly seat...
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From: LT1 land...the "409" of the 90s!
Lets see what Bret can tell us? 
My break ins are not normal...but they seem to work for me Dino 30w bring up to temp on a higher idle a few times to make sure tune is ok and no leaks. Check for good Oil pressure. Re-lash Valves just in case and Change the oil. Then I set it down and take it for a drive slowly uping the RPM range.
If I get a warm and fuzzy that all is well and the Scanner is agreeing I Un-leash it and see where red line is at
IF at any time the scanner is not happy or the trims go whack I re-tune before continuing on.
Some times it takes a few days some times a few hours.
IF you are not using a roller cam this system will not work
My break ins are not normal...but they seem to work for me
Dino 30w bring up to temp on a higher idle a few times to make sure tune is ok and no leaks. Check for good Oil pressure. Re-lash Valves just in case and Change the oil. Then I set it down and take it for a drive slowly uping the RPM range.If I get a warm and fuzzy that all is well and the Scanner is agreeing I Un-leash it and see where red line is at
IF at any time the scanner is not happy or the trims go whack I re-tune before continuing on.
Some times it takes a few days some times a few hours.
IF you are not using a roller cam this system will not work
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From: Tomball (H-Town), TX
My mechanic told me today 200 easy miles then another change at 500 then another at 1000
wont 200 hurt it with all that metal in the filter or are we good also dont u have to run it alittle hard within the first 150 or 200 so the engine doesnt settle as a ***** engine and we cant get every hp we could have out of it
wont 200 hurt it with all that metal in the filter or are we good also dont u have to run it alittle hard within the first 150 or 200 so the engine doesnt settle as a ***** engine and we cant get every hp we could have out of it
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From: The beautiful Kingdom of Bahrain
I was always taught to break it in the way youre going to drive it. That's what I did for the Mustang. This time around for the LT1 I took the advise of most the guys on the net and took it easy. I believe if the engine was built correctly you should be able to not do a breakin. It's the 70000 miles from now it will show you didnt.
The high idle-2000rpm thing is for flat tappets and not applicable here. The current trend is for hard breakins to put a lot of pressure on the rings and seat them before the bore glazes. Search around and you will find articles. Of course you do need to run it a little first to check for leaks and proper operation of everything.
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From: Tomball (H-Town), TX
i was thinking warm up check for ****.. (my mechanics gonna do it and do a test drive) he has the 3000 rpm pill for the MSD thing in there..but after 30-40 miles i think of me driving.. dunno if i should change oil either? im gonna start letting lose alittle bit...
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Drive it around just enough to get comfortable that you didn't leave anything loose, then let it rip. It takes cylinder pressure to seat the rings. All this putting around at low rpm and no throttle isn't applying any pressure to the rings, so they don't seat.
Ever watch a race engine shop build, then dyno an engine? You'll feel sorry for it. They bring it up to temperature, check for leaks, adjust rockers, then make a "short pull". That would be from 5500 - 6500 rpm. If all seems well, they make long pulls. After about the 5th dyno pull, the rings are seated.
Mike
Ever watch a race engine shop build, then dyno an engine? You'll feel sorry for it. They bring it up to temperature, check for leaks, adjust rockers, then make a "short pull". That would be from 5500 - 6500 rpm. If all seems well, they make long pulls. After about the 5th dyno pull, the rings are seated.
Mike
yup break it in like your going to drive it the sooner you can get those rings to seat the better the engine is going to run in the long run
just start her up bring her to temp check for leaks etc etc then let her rip
very the rpms and give her the beans every once in a while and not only hard accelerating but also you want to load the rings in a different way by engine braking if you have an m6 that is easy
doing this will get the rings seated which is one of the most important things if you have a motor failure doing this thats not oil related then the motor wasn't assembled correctly and would have happened eventually anyway
just start her up bring her to temp check for leaks etc etc then let her rip
very the rpms and give her the beans every once in a while and not only hard accelerating but also you want to load the rings in a different way by engine braking if you have an m6 that is easy
doing this will get the rings seated which is one of the most important things if you have a motor failure doing this thats not oil related then the motor wasn't assembled correctly and would have happened eventually anyway
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From: Tomball (H-Town), TX
Originally Posted by 1994Z28Lt1
yup break it in like your going to drive it the sooner you can get those rings to seat the better the engine is going to run in the long run
just start her up bring her to temp check for leaks etc etc then let her rip
very the rpms and give her the beans every once in a while and not only hard accelerating but also you want to load the rings in a different way by engine braking if you have an m6 that is easy
doing this will get the rings seated which is one of the most important things if you have a motor failure doing this thats not oil related then the motor wasn't assembled correctly and would have happened eventually anyway
just start her up bring her to temp check for leaks etc etc then let her rip
very the rpms and give her the beans every once in a while and not only hard accelerating but also you want to load the rings in a different way by engine braking if you have an m6 that is easy
doing this will get the rings seated which is one of the most important things if you have a motor failure doing this thats not oil related then the motor wasn't assembled correctly and would have happened eventually anyway
tomorrow is the day.. new engine/tranny and rear to the test 
