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YOUR RESEARCHMy new C4S - which oil... and what gas ?
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The 2001 996 Turbo was the first Porsche to use the VarioCam Plus technology and a friend who works as a dealer technician told me that one of their technicians spend the whole day trying to diagnose a running problem caused by an owner who hadn't trusted Porsches factory fill and thus changed his oil to SAE 20W-50.
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(Prior owner ran 88) This may have a bigger impact on the things noted in performance than the oil change.
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The heavier oil totally confused the VarioCam plus system and the engine ran poorly.
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I run Sunoco Ultra 93 (or 94), and agree with above that Mobil I 0-40 is fine for the car.
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After 4 full tanks full of gas ran through his 996 and 1 oil change, Phil is an expert.
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I have 4k miles on the new oil and I have this to say (remember I am new to this car, but) the oil prerssure seems slightly higher at idle when hot (was scary low, now almost to 1) At higher rev, the pressure is slightly lower (seemed like it was nearly 5 now around 4) The idle is much smoother AND it shifts with less "jerk" than before (however that may be due to the "New Jerk" behind the wheel) Non of this is scientific, but I am very sensative to change as i am fearful my car may die and leave me holding a major repair..but these minor changes seem ?
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Hi Folks,
After a while too far from a Porsche steering wheel I'm back with a 2003 Carrera 4S upgraded with a PSS9 suspension. I just bought it last week and I already simply love it - it's a bit heavy but the engine is fantastic and the chassis even more precise than I would have expected.
It took me more than 4 months to find the perfect jewel. I saw many 2002/03 C4S and only two appeared totally sane for me, including that one. The only thing I didn't like is the Turbo tail - that will be removed for the original parts during its next service.
I have two questions :
1) In the fuel door there is written "R+M/2 = 93 minimum".
All I can find in my area (SF Bay) is 91. In Europe we use to have 95 and 98, is it the same way to calculate the quality? Does it mean that gas here is crappy?
2) What oil is the best for the 996 engine?
It never freezes here, it's even hot these days.
What do you use for your N.A engine ?
Actually I have a third question even if I don't like to ask this : where to service it ? I'm in Los Gatos and work in San Jose. I'm good with independents who have proven their qualities but don' t want to pay 2000 bucks for an oil service
Thanks in advance for the info. I'm going to take picture and post them here
-Luc
A lot of guys in California run a couple of gallons of unleaded 100 octane in a tank of 91, but I was fine with straiht 91 when I kept the car in LA for the first half of the year. The car definitely felt like it lost a little pop after the first two tanks, and there was a noticeable difference after switching back to east coast 93 octane, but that's purely qualitative, and it's not going to kill you or the vehicle.
RE: comparative octane ratings, the 95 and 98 numbers overseas are Research Octane Numbers, or RON, which are comparatively higher than the Pump Octane Numbers (PON) in the US and Canada
to further add to the confusion, PON is actually a loose average of RON and Motor Octane Numbers (MON)
so 93 PON here is roughly equivalent to 97/98 RON in Europe
91 PON here generally closer to 94/95 RON in Europe
etc
Oil is a tricky subject, search this forum and you'll find there is a lot of debate. Check your Porsche recommended oil list, pick one, and go.
They don't have 93 in CA? They have it in NY (Mobil comes to mind). And Sunoco has Ultra 94.
p.s. I'll stick my neck out and say that I've been happy with the recommended Mobil 1 0W-40
Ninety one is the highest octane rating sold retail in California. BTW, there is a station at the intersection of Santa Teresa and Cottle in San Jose that sells 100 Octane gas.
As for indy mechanics ... there are plenty of those in the Bay Area. See this list:
http://www.pca-ggr.org/files/doc/LOCAL-MECH.doc
I have been going to CT Automotive in Campbell for three years now. All I have is praise for them: Tony & Chris are top rated guys.
For what it's worth, Porsche just admitted that lower octane fuels will not damage their engines or affect warranty. There have been a couple of lawsuits against car manufacturers who do not honor warranty claims because of fuel.
Hi guys,
thanks for the replies.
I understand a bit more now and will keep the equivalence in mind (EU 95 RON = US 91 PON and EU 98 RON = US 93 PON) just like one yard v.s. one meter... or even one dollar v.s. one euro... but why is everything better in Europe ?
I use Castrol 20w40 in my 964 and 10W30 in the BMW.
A friend who is an engineer at Unil-Opal (Shell) told me one day that "top end general purposes oils" like the Mobile 1 0W40, even with their "supersyn" components have a too wide range to be perfect and recommended to use 10W30, 20W40, etc... depending on the temperatures.
He was our advisor in endurance championship where I used the opal jec (equivalent of the Shell helix I think) in 10W30, but I've always been confused by the fact that at the same time, Unil-Opal advertised their 10W60 to be the best protection...
So I actually don't know what to think and will use Mobil 1 since it seems to be good for us.
Oil, gas and tires are points on which I'm really sensible. While gas choice is simpler, discussions about tires and oil choice are always endless.
@ Hans and disco:
Does it make sense to use some 100 octane gas in our catalysed engines ? I thought these were very toxic gas, even the unleaded one that contains phosphorus or something like that, which would kill our catalytic converters.
I used 100 LL (leaded aviation fuel) when racing in Europe. No catalytic of course
thanks for the info
-Luc
I'd use one of the oils Porsche recommends on it's list. Listed below, are a few reasons not to use heavy oil in your Variocam Plus car.
The April 2007 issue of Excellence Magazine addressed the "oil" topic. Two technical experts claim that newer Porsches require the thinner oil to ensure proper VarioCam function.
On page 34 a reader asks a question about using 10W-40 oil (for a Boxster) in Florida vs Mobil 0W-40. He is concerned about using the 0W-40 because 10W-30 or 10W-40 is a "more common fill" in Florida (he also asks about break-in). The response from the Excellence technical expert was as follows.
"Those who suggest higher viscosity oils usually don't understand the whole problem. Oil in engines is no longer just a lubricant. It is also a coolant for the engine as well as a hydralic control fluid for all of the things like VarioCam Plus, hydraulic lifters, and similar systems. If the oil is too high a viscosity, it can affect the way those circuits operate.
The 2001 996 Turbo was the first Porsche to use the VarioCam Plus technology and a friend who works as a dealer technician told me that one of their technicians spend the whole day trying to diagnose a running problem caused by an owner who hadn't trusted Porsches factory fill and thus changed his oil to SAE 20W-50. The heavier oil totally confused the VarioCam plus system and the engine ran poorly.
All of these devices have been designed to run with the SAE 0W-40 oils or other oils that Porsche recommends. Use only those oils recommended in your owners manual - SAE 0W-40, SAE 5W-40, or SAE 5W-50. Porsche is so sure about this decision that it came out with a bulletin recommending these oils for all of its older models as well."
On page 169 (of the same issue) Porsche tech expert Jim Pasha dedicated his entire "Tech Forum" article (6 pages worth) to "Oil". I'm not going to type in all 6 pages of material but I will quote a few short pieces of what Jim reports in his column (he covers a lot of ground in his article).
"Why does Porsche specify such a low lower viscosity rating? The answer comes in two parts. First, in a quest for better fuel economy and longer engine life, Porsche engineers use bearing and cylinder-wall clearances far tighter than what they used previously. This creates less internal drag on components, and lighter oil is more compatible with tight tolerances."
He also says;
"In the latest Porsches, which use 0W-40, the thinner oil is critical to delicate systems that use motor oil as a hydralic activator. VarioCam Plus uses tiny "shafts" of oil created under high pressure to help the system alter valve timing. It is a trick system but it REQUIRES thin oil to work properly
Finally here is what Porsche says on the matter;
http://www.wrightune.co.uk/downloads/approved_oils.pdf
almost all 91 PON gasoline sold in California has a "blend" of oxygenators like toluene and even eth/meth to increase the knock rating artificially, so no matter what you do you're stuck with those factors and so are your cats. Not to treat the matter flippantly, but your cats are firstly designed to handle a wide range of contaminants and furthermore are covered under federal and state emissions warranties for significantly longer than the vehicle. Look inside your owner's manual for your specific vehicle's emissions warranty parameters.
I never ran the 100 in the 996 because I knew I wouldn't do it often enough, so I decided to let it detune to 91 while I kept it in CA. When I've purchased it in the bay area in the past, it's been at a 76 in Palo Alto whose intersection I can't remember, however the internet is full of sites which tell you where you can get 100 octane in your neighborhood.
You know, while we're on the oil topic, does anyone have a good mail order source for 0w-40 in gallons/5qts containers or equivalently cheap quarts?
I have no idea where the nearest walmart to Manhattan is, but I can tell you it's far, and the last quart o oil I bought was like 8 bucks.
At $4 a gallon, plus $180 for the OEM battery, plus an oil and brake fluid change, I figure it's cost me less than $500 for over 2 years of ownership. But, considering that C4S's are holding their values like Boca Raton condos, I figure with depreciation, it's cost me around $19.5K for my ownership experience, which comes out to around $10 per mile.
OK, Tim - your Honda really IS a better investment.
And Jeez, now I've got Tippy on my ***, too.
Where's Wayne when I really need him??
Yeah, but I'm glad that you beat me to it... thanks for stepping in while I spent the afternoon crying over my messed up aero kit spoiler order.
Phil, and expert on fuel and oil...
Made my day!
...I'm here... just catching up on today's posts. I was surprised to see Tim here giving you grief. His radar must have told him to come here to bring you down to earth.
OK so new owner here (7 months) and I was all on the Mobil 1 wagon when the indy shop I chose based on many recommendations from other PCA and local Porsche owners did the switch a roo on me.
My car is high milage and I had it all checked out. I was very surprised (after a 2 week stay in the shop) NO ISSUES...
Now for oil, they changed it to
Shell Helix Ultra
. I asked why and got involved in the old oil debate (again)
Well... I said.."OK" and off we went.
I have 4k miles on the new oil and I have this to say (remember I am new to this car, but) the oil prerssure seems slightly higher at idle when hot (was scary low, now almost to 1) At higher rev, the pressure is slightly lower (seemed like it was nearly 5 now around 4) The idle is much smoother AND it shifts with less "jerk" than before (however that may be due to the "New Jerk" behind the wheel) Non of this is scientific, but I am very sensative to change as i am fearful my car may die and leave me holding a major repair..but these minor changes seem ? good ?
Next I switched to 92 (r+m)/2 method Octane gas. (Prior owner ran 88) This may have a bigger impact on the things noted in performance than the oil change. Again, I dont need to win the Gumball 3000 here, I just want it to run as long as I can and as well as I can.
I read about toluene and other additives... too tricky, too big of deobate based on reaserch vs users opinions - but the gas door clearly states "93 min octane (r+m)/2 method)
Found some 101 race fuel and used this formula
(gal * octane + gal * octane) / total gal = net octane
so with 17 gal tank, 3 gal of the 101 octane "should" put the gas at just above 93.5... I put it in last night and hope to know in a week or so if I can tell a change.
Sorry for all the writing, i look forward to replys on this matter (even a hammer to the scull if needed)
Ed
Your noticable idle and oil pressure improvement is a very common benefit when moving away from Mobil 0W40. Regardless of what some people claim on forums like this, more and more people are moving away from the Mobil 0W40 to a better oil to reduce or eliminate problems such as oil leaks, burning, valve tapping, low oil pressure, idle and high rpm problems as well as to provide better protection to bearings, shafts and chains.
Ed, what viscosity on the shell helix ultra? I'm very interested in knowing what's out there!
The octane mixing formula is good enough, your car can handle a little variance. If you read the manual, it will say that 93 is required, but Porsche recognizes you can't always get it and in a pinch you can drop to as low as 90 and it will change timing to accommodate (if detonation is detected by the wideband knock sensors, which can actually read the flame front and source the detonation very accurately) ,
RE: toluene etc. , reading is good, but you can't run from oxygenators and other additives in the real world. Unleaded race gases like the 101 you're using almost all have something in there to make their knock rating.
Wayne, you know how you can "subscribe" to certain threads?, Well I have an "auto-notify" or any topics or phrases that might pertain to Phil. Phrases like "battery.... sulphated....low miles.... no miles.... 1st gas fill-up.... dash symbol.... vrooom...." You know, all of the usual things.
I love it!
You'll have to show me how to do that, as I've missed out on some prime Phil ribbing opportunities recently after not catching the thread until several hours after others have already given him a hard time. I have a policy of never beating a man when they're already down.
Well, the issue is getting sorted. The spoiler is scheduled to be picked up tomorrow. Dayton is being very good about it and taking the spoiler back and issuing a full refund.
Basically what happened is that I purchased the spoiler from DPS on the assurances that it was an exact copy of the taco wing and was indistinguishable from the OEM version in all details and quality. I go to great lengths to ask lots of questions before I buy so that I set my expectations correctly.
Anyway, the wing arrived yesterday and did not have an adjustable upper plane like the OEM one, the air the intakes were different in design and the paint job was flawed in several places.
I called up Dayton and told him that I was unhappy that the wing was not as described and he immediately offered to take the spoiler back. I can't complain, as he didn't hesitate to make things right. I'm just disappointed to wait 7 weeks for a wing that was not as described. If I'd known that the wing was not adjustable I would have looked elsewhere and not wasted our time by placing an order for a part that I was destined to be unhappy with.
I got a call from the shipper today and they'll be picking up the wing tomorrow... I'm now back on the market for a taco wing, but quickly working on Plan B.
Shell Helix Ultra 5w-40 is what I am running. Here is a link to the shop that does my work. I would like to point your attention to the picture area that was from Porsche Parade. there are some really nice cars in there.
ope you see something you have not seen before or an old favorite taht is worth seeing again and adain.
Cheers all...
http://www.chrisgerman.com/
Ed
Hey, no chance of that with me considering that I'm not in the habit of driving back and forth in my driveway.... I wonder if we know anyone who does that.
Hmm.
Yeah, I still have to change th oil on a Honda. But.... you guys are not going to believe this..... Honda recommends 0-W20 oil! Yes, I said Zero-W-Twenty!
Can you believe that? I just might get a few quarts of 3-in-1 oil and use that instead.
That sucks about the spoiler, but I'm glad to hear the Dayton is taking care of the situation. As for Plan B, you could sell the spoiler to Phil. He won't need an adjustable upper lip because his car never leaves the driveway, so he won't notice the lack of extra downforce. All you have to do is teach him how to do "Vroooom" followed by "Swishhhh" (the air going over the new spoiler). That alone should give him hours of enjoyment on his driveway!
Yeah, the truck picked up the spoiler 5 minutes ago (after me having to take the afternoon off of work because they gave me a 1 to 5pm pickup window - imagine how happy I am right now). Now I just have to get Dayton to process the refund.
The funny thing is that I don't *need* the adjustable wing. The two issues that made me send it back were i) that the wing was misrepresented when I specifically asked the question about it being adjustable and ii) the paint was not a high quality job. If the paint had been flawless it might have been a different decision about sending it back.
I pulled the decklid out the box and saw that there was no paint coverage on two corners, there was debris embedded into the paint on the decklid and the paint around the air intakes was torn in at least 4 places.... yes, a high quality piece of equipment to be installing on my car. I don't think so.
Nothing leaves a bad taste in your mouth more than having to break out the touch-up paint on a new piece of equipment. I had to do it on the aero bumper I bought from DPS, I refused to do it again. It's funny because he said that I'm the first person to ever return a painted part to him. I guess others much have a lower quality standard, because in my eyes the job was terrible. If Dayton had any sense he would stop using such a crappy painter.
Thanks for that. I'm not having much luck finding the M1 jugs in any weight Porsche recommends back east, might have to call the dealer and see what they want for quarts
I have steep grade into the driveway, so I have to back in and front out to avoid scratching my front lip. Maybe I'll buy Wayne's wing and put it on the
front
of the car - not sure it will give me extra clearance, but I won't give a crap if I scratch it up.
If you put a rear spioler on the front of a car, it will create upforce (lift) and the front end will be very light and skidish. However, in your case, I don't think you will notice the difference, because the car has to be moving for the effects to be felt.
<Tim whispers so Phil can't hear> Damn, I love it when Phil posts stuff.... responding to him is more fun than bashing Newbies.
@ted:
I also thought about the blend 91+100 to match some good 95 and have all the poneys running under the hood.
The Shell oil is usually good. I used it in championship during 6 years and never had an issue even at VERY high temperature. This doesn't mean it's better than Mobil or Castrol, but means it's not a crap.
@TimK : what is that ugly signature??? Come on man, it's a Porsche forum here :-P
@itacud: My 4S is silver too and has a turbo tail - that will be removed next service.
Are you in LG too ? Ping me for a glass or lunch
-Luc
Luc,
Yeah, I know that it's ugly, but you didn't have to to rub it in!!!
Just for the record, I did have a sweet looking '04 C2 in Lapis Blue over Gray up until June 1st of this year. Maybe someday I can get back into a P-car. Unitl then, I am stuck with that POS!
This shop has been in the same location and only work on P-cars since ? (way back) I was a caught off guard when the suggestion AWAY from M1 came to me, but I went with it and so far I am very happy with the way the car is running.
The Shell Helix is also what Ferrari runs in their cars. Its available for ~$20/qt at the dealer
Yikes!
The shop I go to buys it in 55/gal drums and sells it for about $8 ? qt (didn't really look too closely as I was in sticker shock at the time)
Good luck finding some, I think its worth the effort (newbe talking)
E
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