All links just say "old cars"
What general years? What styles of engine?
ZDDP enhanced oil is mostly found labelled as "racing oil" ?
What general years? What styles of engine?
ZDDP enhanced oil is mostly found labelled as "racing oil" ?
ZDDP: What cars exactly need this kind of oil?
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*with a new camshaft. Once it is work hardened, not a big deal.
Anything that sees a high pressure sliding load will like zinc
Most older cars without a Catalytic converter...
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Originally Posted By: eljefino
I presume there's a faq on this somewhere.
flat tappets (eg not roller lifters) and high valve spring pressures. eg, hot rods.
Exactly......But for those who do not have gray in their beard, OHV (Over Head Valve......Cam in block) motors with flat (Not roller) tappets.....
OHC (Over Head Cam) motors are not in this category.
I presume there's a faq on this somewhere.
flat tappets (eg not roller lifters) and high valve spring pressures. eg, hot rods.
Exactly......But for those who do not have gray in their beard, OHV (Over Head Valve......Cam in block) motors with flat (Not roller) tappets.....
OHC (Over Head Cam) motors are not in this category.
Originally Posted By: Olas
Anything that sees a high pressure sliding load will like zinc
Bingo. Namely flat tappet lifter/camshaft. IMO the three most critical "zddp" areas of a pushrod style engine are on the cam lobe, fuel pump rod and on the valve/rocker face. The three areas of a sliding load.
Most racing engine today, used in RWD applications are still of a pushrod design. This is usually the target market of the zddp buyer.
Anything that sees a high pressure sliding load will like zinc
Bingo. Namely flat tappet lifter/camshaft. IMO the three most critical "zddp" areas of a pushrod style engine are on the cam lobe, fuel pump rod and on the valve/rocker face. The three areas of a sliding load.
Most racing engine today, used in RWD applications are still of a pushrod design. This is usually the target market of the zddp buyer.
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Curious if moly does much what ZDDP does? The Jeep 4.0 has flat tappets, few oils have the higher ZDDP these days although they can be found if you look (Rotella, Defy). The Jeep 4.0 will run on anything but loves the high moly PYB.
My perception is that moly reduces friction, where ZDDP just keeps high load friction from damaging the sliding surface.
Moly makes things slippery.....ZDDP doesn't. I just keeps highly loaded sliding things from being eroded.
Moly makes things slippery.....ZDDP doesn't. I just keeps highly loaded sliding things from being eroded.
Flat tappet engines with high spring pressure. Most flat tappet engines with mild spring pressure will run fine on API SN oils.
I dose mine with ZDDPlus. I have a little equation I use too haha
Many Mild factory v8s wore out by 100K miles running high zddp oils in the 60's and 70's. Big cam engines aren't going to last past 500hours anyhow - You want a roller there.
^^^^^. What everybody else said re flat rapper enignes, etc. . If you use an oil with 1000 to 1200 ppm MINIMUM zinc/phosphorus (zddp) then you should be OK . However, boosting the levels to 1600 to 2000 ppm won't hurt anyrhing. That is the level the Mobil has in their racing oils +/-.
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With current engine oils the lower ZDDP is a non issue even in older engines (or current flat tappet engines like Cummins). People in the diesel community believed the sky was falling when CJ4 oil was introduced with lower ZDDP levels. Here we are, nearly 10 years later and hundreds of millions of miles are collectively ran every year on CJ4 without a single oil related failure
Almost all oils still use ZDDP; it has its uses. We also need to remember that the old oils didn't always have boatloads of the stuff, either.
Originally Posted By: ARCOgraphite
Many Mild factory v8s wore out by 100K miles running high zddp oils in the 60's and 70's. Big cam engines aren't going to last past 500hours anyhow - You want a roller there.
I'm all for modern engineering like roller cams, overhead cams, Variable valve timing, etc. but its flat out not true that big cammed, flat tappet engines are are going to wear out in 500 hours.
Roller cams have issues too, there is no free ride. If you use a hydraulic roller, you are essentially limited to 6,500 rpm before the lifter pumps up, ie valve float. If you go with a solid roller cam, then the rollers get beat to death when you are dogging the car at idle or low crusiImg rpm. Even choice has limitations.
whether or not engines were worn out at 100,000 miles has more to do with, maintenance, metallurgy and the engineering of oil in the '60's ( in that order of importance) than how much zddp was in the oils.
Z.
Many Mild factory v8s wore out by 100K miles running high zddp oils in the 60's and 70's. Big cam engines aren't going to last past 500hours anyhow - You want a roller there.
I'm all for modern engineering like roller cams, overhead cams, Variable valve timing, etc. but its flat out not true that big cammed, flat tappet engines are are going to wear out in 500 hours.
Roller cams have issues too, there is no free ride. If you use a hydraulic roller, you are essentially limited to 6,500 rpm before the lifter pumps up, ie valve float. If you go with a solid roller cam, then the rollers get beat to death when you are dogging the car at idle or low crusiImg rpm. Even choice has limitations.
whether or not engines were worn out at 100,000 miles has more to do with, maintenance, metallurgy and the engineering of oil in the '60's ( in that order of importance) than how much zddp was in the oils.
Z.
Pushrod engines with flat top lifters need it.
Originally Posted By: zray
whether or not engines were worn out at 100,000 miles has more to do with, maintenance, metallurgy and the engineering of oil in the '60's ( in that order of importance) than how much zddp was in the oils.
Z.
Carburetors & Points ignition contributed also. Cold starts were harder on cars back then, constantly getting the cylinders washed down, more fuel dilution, worse consequences when things were out of whack, etc.
whether or not engines were worn out at 100,000 miles has more to do with, maintenance, metallurgy and the engineering of oil in the '60's ( in that order of importance) than how much zddp was in the oils.
Z.
Carburetors & Points ignition contributed also. Cold starts were harder on cars back then, constantly getting the cylinders washed down, more fuel dilution, worse consequences when things were out of whack, etc.
Originally Posted By: jrmason
With current engine oils the lower ZDDP is a non issue even in older engines (or current flat tappet engines like Cummins). People in the diesel community believed the sky was falling when CJ4 oil was introduced with lower ZDDP levels. Here we are, nearly 10 years later and hundreds of millions of miles are collectively ran every year on CJ4 without a single oil related failure
CJ4 oils still have 1200 ppm of zddp.
With current engine oils the lower ZDDP is a non issue even in older engines (or current flat tappet engines like Cummins). People in the diesel community believed the sky was falling when CJ4 oil was introduced with lower ZDDP levels. Here we are, nearly 10 years later and hundreds of millions of miles are collectively ran every year on CJ4 without a single oil related failure
CJ4 oils still have 1200 ppm of zddp.
Originally Posted By: zray
whether or not engines were worn out at 100,000 miles has more to do with, maintenance, metallurgy and the engineering of oil in the '60's ( in that order of importance) than how much zddp was in the oils.
Z.
I agree. THE SBC was a stone axe of an engine, nothing really exotic about it. Variabilities in Cam lobe bulk case hardening was prob the biggest issue if it was not induction hardened race part.
whether or not engines were worn out at 100,000 miles has more to do with, maintenance, metallurgy and the engineering of oil in the '60's ( in that order of importance) than how much zddp was in the oils.
Z.
I agree. THE SBC was a stone axe of an engine, nothing really exotic about it. Variabilities in Cam lobe bulk case hardening was prob the biggest issue if it was not induction hardened race part.
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