Oil Additive
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Joined: Dec 2004
Posts: 82
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From: Kalamazoo MI
Oil Additive
Is anyone running oil additive in their flat tappet car? I've been reading and hearing about a rash of lifter failures in non-roller motors due to the EPA reducing the amount of zinc and other additives in todays motor oils. After recently installing Edelbrock RPM heads on my car (86), I'm a little concerned with the added spring pressure (dual springs). I've been told add a bottle of Comp. Cams break in oil with the regular dino. oil. I'm a little hesitant to run Rottella, I've been told that it is not friendly to O2 sensors.
Any input?
Any input?
Team Owner
Joined: Aug 2005
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From: Riverside County Southern California
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Synthetic oil, no additves
Synthetic oil does what additives claim would do
$7.49 per quart + oil filter = Good Maintenence
Synthetic oil does what additives claim would do
$7.49 per quart + oil filter = Good Maintenence
Melting Slicks
Joined: Jun 2004
Posts: 3,253
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From: Castro Valley CA
The non friendly component is the zinc and phosphorus which is probably the primary additive used by Comp Cams. I am an Amsoil synthetic oil user in my street driven cars and Redline 10W-40 on my track driven LT1.
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From: Cape Cod, Mass.
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I have always run Mobil 1 in my newer Corvettes 84-present with no engine related problems. I run the Rotella 15 W 40 in the older Vettes.
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Joined: Dec 2004
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From: Kalamazoo MI
Thanks for the input guy's.
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Pro
Joined: Nov 2005
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From: North Bay Ontario
In my higher mileage 85 L98 I've been adding the recommended proportion of Lucas oil stabilizer at each oil change using Mobil 1 synthetic. Does anyone know if it contains the zinc (similar to what was suggested with the STP) that has been eliminated in the SM API classification oils?
Racer
Joined: Dec 2006
Posts: 292
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Is anyone running oil additive in their flat tappet car? I've been reading and hearing about a rash of lifter failures in non-roller motors due to the EPA reducing the amount of zinc and other additives in todays motor oils. After recently installing Edelbrock RPM heads on my car (86), I'm a little concerned with the added spring pressure (dual springs). I've been told add a bottle of Comp. Cams break in oil with the regular dino. oil. I'm a little hesitant to run Rottella, I've been told that it is not friendly to O2 sensors.
Any input?
Any input?
http://www.triflowlubricants.com/Sup...rior_pump.html
Drifting
Joined: Feb 2003
Posts: 1,614
Likes: 163
From: Davis CA
I switched from Mobil 1 to Rotella for the zinc in my ironhead 86. I have heard the "not friendly to O2 sensor and catalytic converter" claim but have never heard anything measurable or factual. I suspect that it is BS or irrelevant. Pollution control equipment is supposed to last at least 100K miles. So maybe it only lasts 90K. Who knows. It probably does nothing but the manufacturer can't say that or the CARB people would be all over their butts because they forced oil for autos to remove the zinc.
Basically, use anything for diesel engines and you will be OK for lubrication.
Basically, use anything for diesel engines and you will be OK for lubrication.
Racer
Joined: Dec 2006
Posts: 292
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I switched from Mobil 1 to Rotella for the zinc in my ironhead 86. I have heard the "not friendly to O2 sensor and catalytic converter" claim but have never heard anything measurable or factual. I suspect that it is BS or irrelevant. Pollution control equipment is supposed to last at least 100K miles. So maybe it only lasts 90K. Who knows. It probably does nothing but the manufacturer can't say that or the CARB people would be all over their butts because they forced oil for autos to remove the zinc.
Basically, use anything for diesel engines and you will be OK for lubrication.
Basically, use anything for diesel engines and you will be OK for lubrication.
Government regulations/pressure presume that everyone is an idiot. Replace the O2 sensor every 50-75K miles and no worries. The nice thing about the '86 is it only has one O2 sensor.
I bought a box of O2 sensors for $13 each. I read somewhere that regularly changing O2 sensors will pay you back on fuel savings - and that was before the recent increases.
Race Director
Joined: Feb 2003
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From: Lake Wylie SC
I think we need to get things straight here. Yes all the new oils (mobil 1 included) as of 2007 no longer have zinc and maganses additives in them. All the newer cars now have roller cams and don't need zinc and maganese. If you have a flat tapet cam, you need these additives for good cam life. Rotilla T has these additives and runs well in a flat tapet engine. Comp Cams also has an additive that contains these. Comp Cams won't warrenty a flat tapet cam if it doesn't have the additives. LT1s and LT4s are roller cam engines and Mobil 1 is just fine.
Racer
Joined: Dec 2006
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I think we need to get things straight here. Yes all the new oils (mobil 1 included) as of 2007 no longer have zinc and maganses additives in them. All the newer cars now have roller cams and don't need zinc and maganese. If you have a flat tapet cam, you need these additives for good cam life. Rotilla T has these additives and runs well in a flat tapet engine. Comp Cams also has an additive that contains these. Comp Cams won't warrenty a flat tapet cam if it doesn't have the additives. LT1s and LT4s are roller cam engines and Mobil 1 is just fine.
All of my cars have over 100K miles on the engines and none of them require oil between changes. I wouldn't use Mobil 1 if I could get it for free because of what it does to old seals.
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Joined: Dec 2004
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From: Kalamazoo MI
Well, I bought a bottle of the comp. cams break-in additive to my recent oil change, then with the next oil change I'll use the Rotella. I've recently change my O2 sensor, so I should be golden with the rotella for awhile. I don't put a lot of miles on my car maybe 1,500 mile a year (weekend warrior).
Pro
Joined: Oct 2007
Posts: 681
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From: Morris County, NJ
Zinc and Phosphorous levels of SM motor oil have been lowered, from approximately 1200 ppm to approximately 700-800 ppm, because these levels are friendlier to the long life of the cat. Additional additives like calcium and boron have been added to address the lowering of Zinc and Phosphorous levels.
If you want to boost these levels back to the levels of SL rated oil, add half a bottle of GM Engine Oil supplement (EOS) which is used for new engine or cam break in. It was recently remformulated, but the product has been around for at least 35 years
If you want to boost these levels back to the levels of SL rated oil, add half a bottle of GM Engine Oil supplement (EOS) which is used for new engine or cam break in. It was recently remformulated, but the product has been around for at least 35 years
