GM EOS discontinued...now what for ZDDP?
- Thread starter Daniel J. Stern
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just asking... and i know i'm gonna sound like a noobie... but what is a flat tappet engine?
Daniel, what exactly is the optimal range for ZDDP in a flat-tappet engine? I'm trying to figure out how much SLOB to add to my Castrol GTX.....?
Benny, a flat-tappet engine has 'flat' valve lifters that ride (slide) directly on the camshaft lobes, as opposed to a 'roller' valve lifter which has roller bearings that ride (roll) on the camshaft.
The roller bearings reduce friction on the lifters/cam.
http://theoildrop.server101.com/forums/s...true#Post838665
See my above post and the links.
If you know more about ZDDP requirements than Bob Olree then I think you should work at GM as a power train engineer or be the Chairman of ISLAC like he was. He said it was non-issue.
My study on the topic for my 1985 P-911 lead me to conclude reduced levels of ZDDP in SM rated oils is not an issue for flat tappets after proper break-in for ‘normal’ cam/spring rates in non-racing applications.
Still worried ? Look for AECA A3/B4 rating which, as I understand, has even more critical tests on flat-tappet valve train wear. Europeans run oils a lot longer.
Still worried (or race/ aggressive cam/springs) ? Some companies like Castrol are advertising “high anti-wear” additives for cars older than 1993. See Syntec and GTX 20W50. I think Mobil may have some also. This may be marketing See http://www.lnengineering.com/oil.html
Adding GM’s EOS or SLOB ? I don’t like the idea. I would need to add 1 qt to 12qts to have meaningful difference then I worry about viscosity and other things (like proper suspension)
If worried, you should know ZDDP is sacrificial and gets used up. It’s hard to know how much you start with and how fast it’s consumed. Also the stuff like PP/QS and SynPower seem to be running about 800ppm which is down from the 1200ppm I think is in GTX. That’s only 33% less. Look for more boron which also helps.
See my above post and the links.
If you know more about ZDDP requirements than Bob Olree then I think you should work at GM as a power train engineer or be the Chairman of ISLAC like he was. He said it was non-issue.
My study on the topic for my 1985 P-911 lead me to conclude reduced levels of ZDDP in SM rated oils is not an issue for flat tappets after proper break-in for ‘normal’ cam/spring rates in non-racing applications.
Still worried ? Look for AECA A3/B4 rating which, as I understand, has even more critical tests on flat-tappet valve train wear. Europeans run oils a lot longer.
Still worried (or race/ aggressive cam/springs) ? Some companies like Castrol are advertising “high anti-wear” additives for cars older than 1993. See Syntec and GTX 20W50. I think Mobil may have some also. This may be marketing See http://www.lnengineering.com/oil.html
Adding GM’s EOS or SLOB ? I don’t like the idea. I would need to add 1 qt to 12qts to have meaningful difference then I worry about viscosity and other things (like proper suspension)
If worried, you should know ZDDP is sacrificial and gets used up. It’s hard to know how much you start with and how fast it’s consumed. Also the stuff like PP/QS and SynPower seem to be running about 800ppm which is down from the 1200ppm I think is in GTX. That’s only 33% less. Look for more boron which also helps.
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for some visuals BennyL;
Roller lifters;
http://images.google.com/images?hl=en&q=roller+lifter&btnG=Search+Images&gbv=2
Flat Tappets, the first image sums it up pretty well why the concern about the current generation of oil;
http://images.google.com/images?hl=en&am...G=Search+Images
My only beef with this stand of oil companies suggesting the heavy weights, or "racing oils" is I DON"T USE heavy weights in my daily drivers. Nor would I use a 20w50 during the winter. I want a 10w30 or 10w40 thats flat tappet acceptable.
Alex.
Roller lifters;
http://images.google.com/images?hl=en&q=roller+lifter&btnG=Search+Images&gbv=2
Flat Tappets, the first image sums it up pretty well why the concern about the current generation of oil;
http://images.google.com/images?hl=en&am...G=Search+Images
My only beef with this stand of oil companies suggesting the heavy weights, or "racing oils" is I DON"T USE heavy weights in my daily drivers. Nor would I use a 20w50 during the winter. I want a 10w30 or 10w40 thats flat tappet acceptable.
Alex.
I think the flat-tappet/ZDDP concern is only part of the question. I'll wager that most of the ZDDP in engine oil is used up to lubricate the piston compression ring. The top sealing edge of the piston has to be the point of maxium pressure in an engine, and also where oiling is at a minimum.
This is where ZDDP is primarily needed.
I'll also wager that a used oil analysis won't show true wear on compression rings, since most of the wear material will be blown out in the exhaust gases instead of going into the oil.
It could be that the true cost of using these SM oils with low ZDDP won't be known for a few years yet, when our engines start drinking oil, losing compression and wearing out prematurely......
This is where ZDDP is primarily needed.
I'll also wager that a used oil analysis won't show true wear on compression rings, since most of the wear material will be blown out in the exhaust gases instead of going into the oil.
It could be that the true cost of using these SM oils with low ZDDP won't be known for a few years yet, when our engines start drinking oil, losing compression and wearing out prematurely......
Did anybody mention Valvoline VR1 Racing Oil? It has 1300 ppm zinc and comes in 10w30. Can use wherever SM oil is called for (so says Valvoline).
Use Valvoline Syn Oil Treatment it is full of additives. Also, you have more seniority than me.... glad to see you back after a four year absence of post... or are you just like me sitting and watching until the time is right to post... I remember I remember... sitting in the tree stand waiting...
I will check into the size of the bottles next time im at my storage facility. I have no idea what the level of zinc is, I picked them up at Big Lots a few years ago for my wifes 93 Caprice but I dont think we have that many oil changes left in that car. I did not pay much for them.
Hey Daniel...some light reading on the subject firstly.....
http://forums.noria.com/eve/forums/a/tpc/f/616604995/m/3011052071
and HotRod chimed in with a very well written article....
http://www.hotrod.com/techarticles/engine/flat_tappet_cam_tech
Comp Cams has made their choice to address the issue...
"Comp is recommending that flat-tappet camshaft owners use Shell’s Rotella T oils. Since that line of oil is primarily developed for diesel engines, Comp says the oil makeup contains many of the additives that many of the newer oils are lacking. "
And lastly.....the old school muscle cars I am around all use this product from Hughes....it works well with any conventional or synthetic oils....
http://www.hughesengines.com/partDetail.asp?partID=12866
Hope some of this may help you man....
http://forums.noria.com/eve/forums/a/tpc/f/616604995/m/3011052071
and HotRod chimed in with a very well written article....
http://www.hotrod.com/techarticles/engine/flat_tappet_cam_tech
Comp Cams has made their choice to address the issue...
"Comp is recommending that flat-tappet camshaft owners use Shell’s Rotella T oils. Since that line of oil is primarily developed for diesel engines, Comp says the oil makeup contains many of the additives that many of the newer oils are lacking. "
And lastly.....the old school muscle cars I am around all use this product from Hughes....it works well with any conventional or synthetic oils....
http://www.hughesengines.com/partDetail.asp?partID=12866
Hope some of this may help you man....
eos has been discontinued..on track performance said they got the last batch...try using torco's assembly lube i pour the 12 oz. in my oil change every change..it is a full synthetic formula.has ton's of moly in it along with alot of zinc and phos.and other additives.
Just saw at the Ford Truck site a post saying AC Delco still supplies the EOS under it's own label. Check out this link. Just select EOS in the drop down menu. Now the question is can we find this for sale anywhere?
*bump*
Looks like GM EOS is back: http://www.gmpartsdirect.com/results.cfm?singlepart=1&partnumber=1052367
Anyone want to do a VOA on this? I'm guessing the ZDDP levels have gone down.
- Scott
Looks like GM EOS is back: http://www.gmpartsdirect.com/results.cfm?singlepart=1&partnumber=1052367
Anyone want to do a VOA on this? I'm guessing the ZDDP levels have gone down.
- Scott
Crashbox
$100 Site Donor 2026
Yeah, I'd like to see a VOA too- you may well be correct on the ZDDP reduction.
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