What oil to run in rebuilt engine?
#1
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Car: 1992 Camaro RS
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What oil to run in rebuilt engine?
The title tells everything: what oil should I use to fire up a freshly rebuilt engine?
On some sites I saw to run full organic oil as it is required in the first few hundred miles. Is that true or just some kind of urban legend?
On some sites I saw to run full organic oil as it is required in the first few hundred miles. Is that true or just some kind of urban legend?
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Car: 1989 IROC-Z Camaro 'Vert.
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Re: What oil to run in rebuilt engine?
Not urban legend - synthetic oil is too 'fine' and won't allow the rings to break-in. That's the whole point of synthetic, it can get to places that dino oil can't, which is part of why it cleans better.
It's a SBC right? I'd say 10W-30, 5W-30 wouldn't hurt though.
It's a SBC right? I'd say 10W-30, 5W-30 wouldn't hurt though.
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Re: What oil to run in rebuilt engine?
Might want to tell the manufacturers about that, they're using synthetic for the factory fill on all their new engines.
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Car: 1992 Camaro RS
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Re: What oil to run in rebuilt engine?
Seems like this is going to be the same that I read at other places as well.
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Re: What oil to run in rebuilt engine?
Well it's not like you'll hurt anything by not breaking it in with synthetic. You're also not going to hurt anything by breaking it in with synthetic, too. Either way you can't lose.
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Re: What oil to run in rebuilt engine?
Yes, they are. Cast iron cylinder walls, cast iron rings with or without moly facing, aluminum pistons, steel valvetrain components... that kind of engine technology hasn't changed in a looooooooooooong time.
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Re: What oil to run in rebuilt engine?
Because you've read rumors and old wive's tales, not facts from people who produce lubricants and build engines.
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Re: What oil to run in rebuilt engine?
GM uses Mobil 1 for the factory fill in the Corvette and Camaro.
#12
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Re: What oil to run in rebuilt engine?
True i have read companies do break ins on factory motors with synthetics.
For my 2 motors, I used regular conventional 10w-30 for initial break in for first 25-50miles. Changed oil to same stuff for another 25 miles or so when doing hard pulls for break in. 1st gear pulls, lower load, higher rpms. Then moved on to 2-3rd gear heavy load pulls to 90% of max rpm.
After that and likely before 100 miles, i went straight synthetic and proceeded to go racing. Never had a problem.
Now if you have a Flat TAPPET cammed motor, you will need a high zinc oil for lubrication on cam break in. They sell special oils for that as most modern oils now do not have proper lubricants for flat tappet cam break ins.
My motors are hydraulic rollers, so you can just fire up, check for leaks and go drive.
One reason to break in on cheap conventional oil is because its CHEAP and you need to change it out a few times after little mileage on the motor. Dont waste synthetic for that
For my 2 motors, I used regular conventional 10w-30 for initial break in for first 25-50miles. Changed oil to same stuff for another 25 miles or so when doing hard pulls for break in. 1st gear pulls, lower load, higher rpms. Then moved on to 2-3rd gear heavy load pulls to 90% of max rpm.
After that and likely before 100 miles, i went straight synthetic and proceeded to go racing. Never had a problem.
Now if you have a Flat TAPPET cammed motor, you will need a high zinc oil for lubrication on cam break in. They sell special oils for that as most modern oils now do not have proper lubricants for flat tappet cam break ins.
My motors are hydraulic rollers, so you can just fire up, check for leaks and go drive.
One reason to break in on cheap conventional oil is because its CHEAP and you need to change it out a few times after little mileage on the motor. Dont waste synthetic for that
#13
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Re: What oil to run in rebuilt engine?
True i have read companies do break ins on factory motors with synthetics.
For my 2 motors, I used regular conventional 10w-30 for initial break in for first 25-50miles. Changed oil to same stuff for another 25 miles or so when doing hard pulls for break in. 1st gear pulls, lower load, higher rpms. Then moved on to 2-3rd gear heavy load pulls to 90% of max rpm.
After that and likely before 100 miles, i went straight synthetic and proceeded to go racing. Never had a problem.
Now if you have a Flat TAPPET cammed motor, you will need a high zinc oil for lubrication on cam break in. They sell special oils for that as most modern oils now do not have proper lubricants for flat tappet cam break ins.
My motors are hydraulic rollers, so you can just fire up, check for leaks and go drive.
One reason to break in on cheap conventional oil is because its CHEAP and you need to change it out a few times after little mileage on the motor. Dont waste synthetic for that
For my 2 motors, I used regular conventional 10w-30 for initial break in for first 25-50miles. Changed oil to same stuff for another 25 miles or so when doing hard pulls for break in. 1st gear pulls, lower load, higher rpms. Then moved on to 2-3rd gear heavy load pulls to 90% of max rpm.
After that and likely before 100 miles, i went straight synthetic and proceeded to go racing. Never had a problem.
Now if you have a Flat TAPPET cammed motor, you will need a high zinc oil for lubrication on cam break in. They sell special oils for that as most modern oils now do not have proper lubricants for flat tappet cam break ins.
My motors are hydraulic rollers, so you can just fire up, check for leaks and go drive.
One reason to break in on cheap conventional oil is because its CHEAP and you need to change it out a few times after little mileage on the motor. Dont waste synthetic for that
#18
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Re: What oil to run in rebuilt engine?
What my machinist says about synthetic is it doesn't allow the rings to seat properly because it prohibits wear. That's why I run organic oil for the first 1,000 miles. Then switch to Mobil1
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Car: 1992 Camaro RS
Engine: 3.1L V6
Transmission: 700-R4
Axle/Gears: 3.23
Re: What oil to run in rebuilt engine?
What brand do you suggest, Ase? Who makes full organic oil?
#21
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Re: What oil to run in rebuilt engine?
Ya know? I guess whatever works for you. I suppose the worst that could happen if you switch to synthetic too soon is excess oil cunsumption. Cylinder finish will have a large effect on this. Having the correct finish for the rings you use is important.
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Re: What oil to run in rebuilt engine?
Orr89RocZ has the real reason to break in with conventional oil.
#25
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Re: What oil to run in rebuilt engine?
I've been running M1 Hi Mileage 5W30 in my 88 LB9 for years. Winter and summer.
Don't use the Fram orange can of death filters. Wix makes a good filter. So does K&N.
And I also recommend going and reading the BITOG forums. More than you ever wanted to know about lubrication.
Don't use the Fram orange can of death filters. Wix makes a good filter. So does K&N.
And I also recommend going and reading the BITOG forums. More than you ever wanted to know about lubrication.
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Re: What oil to run in rebuilt engine?
Old thread...do guys listen to their builders suggestions or ask the internet instead?
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