Motor Oil
#61
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To answer the digression - we have yet to alter the idle with the ST.
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Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014
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Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
![thumbsup](https://rennlist.com/forums/graemlins/bigok.gif)
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
![thumbsup](https://rennlist.com/forums/graemlins/bigok.gif)
#62
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You're asking the wrong person! For full disclosure, I don't really know jack **** about this stuff. But it sounds logical, what you ended up doing is probably what I would have done, provided that I was happy with the idle of the car with milder cams -- whether it's wrong or right.
#63
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Im switching from Castrol 20/50 to Golden Spectro as soon as my case of oil shows up.
A writeup -over 1500 grams of ZDDP. Golden_Spectro_FAQ
This oil was awesome in my air cooled motorcycle motors.. [GSXR-750s]
A writeup -over 1500 grams of ZDDP. Golden_Spectro_FAQ
This oil was awesome in my air cooled motorcycle motors.. [GSXR-750s]
#64
Nordschleife Master
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Im switching from Castrol 20/50 to Golden Spectro as soon as my case of oil shows up.
A writeup -over 1500 grams of ZDDP. Golden_Spectro_FAQ
This oil was awesome in my air cooled motorcycle motors.. [GSXR-750s]
A writeup -over 1500 grams of ZDDP. Golden_Spectro_FAQ
This oil was awesome in my air cooled motorcycle motors.. [GSXR-750s]
I think you'd have to buy a lot of that oil before coming up with 1.5kg of ZDDP. ;-)
#65
Burning Brakes
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From what I've read, it depends, with the optimum range going from 1200ppm to 1500ppm depending on how high detergent the oil is (the lower the detergency, the less needed)
#66
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#67
Burning Brakes
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The internet is pretty much the only place you can get good oil these days. Shipping prices aren't really all that bad, about the same as an extra quart, maybe a little more. The closest place with Brad Penn to San Antonio is north of Houston.
#69
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Here's an interesting story for you:
My 93 Trooper was having some problems with low oil pressure, not matter what or when. I've always run premium synthetic in since I bought it 2004.
I took it to a shop and had them do their engine flush with MileGuard.
http://www.cllubeplus.com/engineservices.html
A few days after I had the flush done, I ranked up the Trooper, drove down the street, and began hearing a terrible metallic groan seemingly independent of RPM. Check Engine light came on, I pulled over and shut it off. Had a look-see, saw no issues under the hood, fired it back up, all was normal, save for one thing:
My oil pressure had doubled, and has stayed twice as high across the board since that odd event happened. At start-up, I get 55 psi, and running hot I get 30 psi. The Trooper runs stronger now, and smoother, too.
??
My 93 Trooper was having some problems with low oil pressure, not matter what or when. I've always run premium synthetic in since I bought it 2004.
I took it to a shop and had them do their engine flush with MileGuard.
http://www.cllubeplus.com/engineservices.html
A few days after I had the flush done, I ranked up the Trooper, drove down the street, and began hearing a terrible metallic groan seemingly independent of RPM. Check Engine light came on, I pulled over and shut it off. Had a look-see, saw no issues under the hood, fired it back up, all was normal, save for one thing:
My oil pressure had doubled, and has stayed twice as high across the board since that odd event happened. At start-up, I get 55 psi, and running hot I get 30 psi. The Trooper runs stronger now, and smoother, too.
??
#70
Reanimator
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Can't explain the oil pressure thing; first car was a 66 mustang with a 289; changed to mobile 1 5w20 I think for the rest of it's life, if I remember correctly from about 70K on, never had an issue. Yes, lower oil pressure on idle, and lower than with 10w40 at 3000 rpm. Still, never had a problem with the engine. Back in the 70's, explanation was that the slightly thinner oil but with longer carbon molecule chains just had less back pressure at the oil pressure sender, but still had excellent lubrication. So unless you don't have enough pressure to keep your hydraulic tappets full, I'm not sure it's a problem. Oil pressure doesn't equal lubrication. It only measures resistance to oil flowing through the engine.
#71
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I think AO is correct and the problem is viscosity breakdown. I have had the problem the past three summers here in Texas. First was with Mobil 1, 20W50, then with Delvac, then Brad Penn 20W50 and now this summer with Royal Purple, again 20W50. My problem appears to be only when everything is hot and I suddenly get into stop and go traffic. I have an oil temp gauge in the car (see avatar) when I'm running for any length of time the oil temp follows the water temp., but when I get in stop and go traffic the oil temp suddenly climbs and the pressure goes down. On several occasions I get the low oil pressure light and the dig dash warning. This last oil change, last week, I split my oil filter to check for contamination or bearing material. The filter looked perfect, no silver or copper color, no big chunks of anything, didn't even look that dirty.
I think the problem is lack of air flow over my external oil cooler in stop and go traffic. I also think one fix will be to add the oil cooler back into the radiator along with the external cooler. The radiator cooler will continue to get air flow from the fans even when in stop and go traffic. Plus I'll be adding an additional quantity of oil to the system. Greg Brown is developing this system now (see radiator thread) with the necessary hoses to add the 2nd oil cooler in the radiator. I also plan to at least check the spring pressure on the oil pressure relief valve.
I think the problem is lack of air flow over my external oil cooler in stop and go traffic. I also think one fix will be to add the oil cooler back into the radiator along with the external cooler. The radiator cooler will continue to get air flow from the fans even when in stop and go traffic. Plus I'll be adding an additional quantity of oil to the system. Greg Brown is developing this system now (see radiator thread) with the necessary hoses to add the 2nd oil cooler in the radiator. I also plan to at least check the spring pressure on the oil pressure relief valve.
#73
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If so, do you have a fan on the cooler?
Jim Page discovered many years ago the need for a good fan on an external oil cooler.
This is his setup:
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#74
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And the magic number when bad things start to happen is 212 F, strange that that is exactly where they test the hot vis at to find out how much additive to to put in the oil, or in most cases how little they can put in.
I think AO is correct and the problem is viscosity breakdown. I have had the problem the past three summers here in Texas. First was with Mobil 1, 20W50, then with Delvac, then Brad Penn 20W50 and now this summer with Royal Purple, again 20W50. My problem appears to be only when everything is hot and I suddenly get into stop and go traffic. I have an oil temp gauge in the car (see avatar) when I'm running for any length of time the oil temp follows the water temp., but when I get in stop and go traffic the oil temp suddenly climbs and the pressure goes down. On several occasions I get the low oil pressure light and the dig dash warning. This last oil change, last week, I split my oil filter to check for contamination or bearing material. The filter looked perfect, no silver or copper color, no big chunks of anything, didn't even look that dirty.
I think the problem is lack of air flow over my external oil cooler in stop and go traffic. I also think one fix will be to add the oil cooler back into the radiator along with the external cooler. The radiator cooler will continue to get air flow from the fans even when in stop and go traffic. Plus I'll be adding an additional quantity of oil to the system. Greg Brown is developing this system now (see radiator thread) with the necessary hoses to add the 2nd oil cooler in the radiator. I also plan to at least check the spring pressure on the oil pressure relief valve.
I think the problem is lack of air flow over my external oil cooler in stop and go traffic. I also think one fix will be to add the oil cooler back into the radiator along with the external cooler. The radiator cooler will continue to get air flow from the fans even when in stop and go traffic. Plus I'll be adding an additional quantity of oil to the system. Greg Brown is developing this system now (see radiator thread) with the necessary hoses to add the 2nd oil cooler in the radiator. I also plan to at least check the spring pressure on the oil pressure relief valve.