50 weight in a 355?
50 weight in a 355? Talked to my builder today about what oil to run after breaking in my 355 and he told me to run 50 weight oil. Common knowledge tells me to stick with a 40 weight at the most but what do you guys think? He is more of an old school builder, but he knows his SBCs very well. I was going to run 0W-40 Mobil 1 but after he told me this should I run 15W-50?
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i use 10w40 dino oil (i use to use rotella, it had zinc in it not sure anymore) for initial start up and break in, i use the cheapest filters i can find.
i do an oil change just after the initial start up.. basicly if the engines runnning good i will bring it up to temperature fluctuating the rpms.. i shut it off, let it cool off and change oil and filter again, usually check the filter for abnormal debris, start it back up, readjust valves.. i run that oil change about 250 miles,then i switch to mobil1 5w30 or 10w40 synthetic and a wix filter, drive that another 500miles and change oil and filter again.....
added this, if there is a written warranty use what he said and have receipts and a witness thats what you used.
if its a pavement warranty i would use a thinner oil myself to make sure the entire engine gets oil as quick as possible....
i do an oil change just after the initial start up.. basicly if the engines runnning good i will bring it up to temperature fluctuating the rpms.. i shut it off, let it cool off and change oil and filter again, usually check the filter for abnormal debris, start it back up, readjust valves.. i run that oil change about 250 miles,then i switch to mobil1 5w30 or 10w40 synthetic and a wix filter, drive that another 500miles and change oil and filter again.....
added this, if there is a written warranty use what he said and have receipts and a witness thats what you used.
if its a pavement warranty i would use a thinner oil myself to make sure the entire engine gets oil as quick as possible....
Last edited by brucer; Sep 25, 2010 at 09:28 PM.
Did he spec thick because he was not capable of setting up tight clearances???
Did he take into account the LT1 oil pump drive which is often damaged by HV pumps? Given that I would seriously worry about running 50wt in it long term as thick oil is undo load on the drive just like a HV pump is.
If he set it up for 50wt. you have little choice as it is too late now.
Most guys with modern knowledge though seem to like thin oils for less parasitic loss, at least at a modest HP level like this.
Did he take into account the LT1 oil pump drive which is often damaged by HV pumps? Given that I would seriously worry about running 50wt in it long term as thick oil is undo load on the drive just like a HV pump is.
If he set it up for 50wt. you have little choice as it is too late now.
Most guys with modern knowledge though seem to like thin oils for less parasitic loss, at least at a modest HP level like this.
Did he spec thick because he was not capable of setting up tight clearances???
Did he take into account the LT1 oil pump drive which is often damaged by HV pumps? Given that I would seriously worry about running 50wt in it long term as thick oil is undo load on the drive just like a HV pump is.
If he set it up for 50wt. you have little choice as it is too late now.
Most guys with modern knowledge though seem to like thin oils for less parasitic loss, at least at a modest HP level like this.
Did he take into account the LT1 oil pump drive which is often damaged by HV pumps? Given that I would seriously worry about running 50wt in it long term as thick oil is undo load on the drive just like a HV pump is.
If he set it up for 50wt. you have little choice as it is too late now.
Most guys with modern knowledge though seem to like thin oils for less parasitic loss, at least at a modest HP level like this.
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If he means 20w50 or 15w50, I can see that with larger bearing clearances.
If he means straight 50, no way... That is retarded.
No need for thick as tar oils when cold. That is 1950's technology.
If he means straight 50, no way... That is retarded.
No need for thick as tar oils when cold. That is 1950's technology.
I don't have #s but its a stock bottom end rebuild with ARP boilts/studs and the larger pistons as the only difference. Clearances are stock. I just talked to him, he was under the impression I was using is as a straight track car, he told me a 30 weight would be fine. Thanks guys
