which oil
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
In a new engine, no.
In a good running 50,000 mile engine down here with ambient cold start 80° temps, and a 195° tstat, don't think it would hurt, especially synthetic.
But stock Melling reliefs are 60psi and hv come with 70, so that alone is a no no. Try never to run over relief.
In a good running 50,000 mile engine down here with ambient cold start 80° temps, and a 195° tstat, don't think it would hurt, especially synthetic.
But stock Melling reliefs are 60psi and hv come with 70, so that alone is a no no. Try never to run over relief.
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
Here's an example.
This engine works pretty hard, tow van. I put it together with modern tight clearances. I did use 20w50 Mobile, hv pump, dual filters, 195tstat,
approx 20,000 miles, chrome rings, towed a 6000# trailer over 4500 miles with only 1/2 pint oil loss.
I did loose the ytt head bolts later.
I'm no advocate of heavy oil, but under some conditions in this heat here, it certainly doesn't hurt imo.
These don't look bad at all, no cold startup lack of oil evidence. Pistons are scratch free.
This engine works pretty hard, tow van. I put it together with modern tight clearances. I did use 20w50 Mobile, hv pump, dual filters, 195tstat,
approx 20,000 miles, chrome rings, towed a 6000# trailer over 4500 miles with only 1/2 pint oil loss.
I did loose the ytt head bolts later.
I'm no advocate of heavy oil, but under some conditions in this heat here, it certainly doesn't hurt imo.
These don't look bad at all, no cold startup lack of oil evidence. Pistons are scratch free.
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
Your right, this has been debated and rehashed over and over again in countless threads. I like to see 30 PSI hot at idle. I get that with 10W-40. I like Amsoil 10W-40 because of the 1400 PPM Zinc and the proven better protection of a true synthetic and, yes, I have a roller cam. That is what I run. Use what you want. If you like to see 70 PSI cold at idle and think that is better for you engine it is your engine. Do what you want. If you want to use racing oil in a street engine, do it. If you want to use diesel oil in a gas engine, be my guest. You should really have a valid reason why you make these choices before making them though. I made my point in earlier posts. 
Last edited by 63mako; Mar 13, 2010 at 12:42 AM.
Melting Slicks
Joined: May 2009
Posts: 3,079
Likes: 314
2024 C3 of the Year Finalist - Unmodified
Thanks for your advice, I mean it. If I can't trust my rebuilder to select the oil, then why did I give him my matching numbers BB in the first place? Why did I let him decide what needed to be done to the engine and what components to use? I know a fair amount about a lot of things, but engine rebuilding isn't one of them. That is why I chose to rely on experts, people that have spent their entire careers working on old corvettes and rebuilding engines, people that own real L88s and tri-powers. I would take their "old school" and "silly" advice any day over that of the part-time hobbyists on this forum, whether they are well informed or not. When I needed surgery, I sought out the most experienced surgeon I could find for that procedure. He told me what I needed and I trusted him to do it. Same with my engine.
Race Director
Joined: May 2005
Posts: 10,674
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From: Millington Illinois
St. Jude Donor '08-'09
That is why I chose to rely on experts, people that have spent their entire careers working on old corvettes and rebuilding engines, people that own real L88s and tri-powers. I would take their "old school" and "silly" advice any day over that of the part-time hobbyists on this forum, whether they are well informed or not.
Two recent builds for me that have been documented here on the forum, a 500+hp 383 tripower with a 150 nitrous setup and an L88 pump gas clone. It is odd you refered to tripower and l'88's. 30 years experience building engines and If old school is 15 years drag racing starting in the early 70's I guess I qualify there too. Whatever floats your boat.
Last edited by 63mako; Mar 13, 2010 at 09:53 AM.
Melting Slicks
Joined: May 2009
Posts: 3,079
Likes: 314
2024 C3 of the Year Finalist - Unmodified
Definitely going to ask him about 10W40 and zinc levels real soon. I too am concerned about my high oil pressure and the strain that heavy oil is putting on the engine internals. This engine is very rarely ever going to see WOT. Also plan to change the oil and filter before the first 200 miles.
Melting Slicks
Joined: Apr 2005
Posts: 2,777
Likes: 105
Definitely going to ask him about 10W40 and zinc levels real soon. I too am concerned about my high oil pressure and the strain that heavy oil is putting on the engine internals. This engine is very rarely ever going to see WOT. Also plan to change the oil and filter before the first 200 miles.
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Advanced
Joined: Feb 2010
Posts: 82
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From: CT
Good day gentlemen. I want to share a personal experience. I have a 383 SB in my Camaro that has a billet mechanical roller cam and a bronze distributor gear. My engine builder suggested 10w-40w which is what I used for years. I noticed that hot at idle around 800 RPM's my oil pressure was around 15 psi. This concerned me but I lived with it. I always check my dist. gear for wear at every oil change knowing that is designed to wear but I did not have any. I thought great this is lasting longer than I expected. Then I had a great idea, let’s try 20w-50. So I put in Castrol GTX 20w-50. Wow, my oil pres. is up to around 25 psi. At idle hot, cool. Next oil change I check the dist. gear it was halfway eaten up from the added pressure of turning the pump. I went back to 10w-40 with a new gear and things are happy again.
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Joined: Feb 2010
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From: CT
EJ
Acct suspended by request 19 April 2011
Joined: Jul 2009
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From: La Porte In
Oil viscosity
I have a 1978. Manual says 10w30 or 10w40. Depending on climate. On the West Coast for years I used 10w40 the years I lived there. Here in the Great Lakes I always have used 10w30. Using 10w30 Valvoline SynPower in everything I own including lawn mower now for over 2 years.
Gary
Gary
Thread Starter
Racer
Joined: Oct 2009
Posts: 280
Likes: 1
From: cleveland Ohio
as i said at the start of this thread,im afraid of using synthic oil, ive heard its bad for newer cams.but i also know modern conventional oil has less antiwear additives etc., so i called napa to see what they had to say.a guy at the parts store said alot of his customers use valvoline plus a 4 ounce bottle of federal moguls assembly lube no. z55400 mixed together with each oil change. ill be calling fed mog monday to see whats in this assembly lube and to get there opinun on mixing it with regular oil.i just cant find a conventional oil thats up to snuff on the parts shelf. i know i need zinc and phospates etc. still a little confused, thanks, tom
Race Director
Joined: May 2005
Posts: 10,674
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From: Millington Illinois
St. Jude Donor '08-'09
as i said at the start of this thread,im afraid of using synthic oil, ive heard its bad for newer cams.but i also know modern conventional oil has less antiwear additives etc., so i called napa to see what they had to say.a guy at the parts store said alot of his customers use valvoline plus a 4 ounce bottle of federal moguls assembly lube no. z55400 mixed together with each oil change. ill be calling fed mog monday to see whats in this assembly lube and to get there opinun on mixing it with regular oil.i just cant find a conventional oil thats up to snuff on the parts shelf. i know i need zinc and phospates etc. still a little confused, thanks, tom
http://forums.corvetteforum.com/c3-t...ppet-oils.html
Advice to the guy using Valvoline Synpower 10W-30 in his flat tappet corvette good luck with that. Think your better off using that in your lawnmower and modern roller tappet engines. It has less than 800 PPM zinc and will take out your cam sooner or later
