Re: All about oil???? | <– Date –> <– Thread –> |
From: Peter Pless (ferrarilist![]() |
|
Date: Fri, 28 Mar 2008 23:31:33 -0700 (PDT) |
So I decided, since winter is upon us here in Aus, to put the 5W40 in the car...then I ran over a rock, put a hole in the sump, and watched all the oil run down the drain. I wasn't all that impressed :) Oh well. -----Original Message----- From: LarryT [mailto:l02turner [at] comcast.net] Sent: Thursday, 27 March 2008 11:54 AM To: Peter Pless Cc: The FerrariList Subject: Re: [Ferrari] All about oil???? Thanks for the article - I think I'll try some of the Cam stuff - Larry T (66 MGB, 74 911, 91 300D) www.youroil.net for Oil Analysis and Weber Parts Test Results http://members.rennlist.com/oil PORSCHE POSTERS! youroil.net 800-583-8601 Weber Carb Info http://members.rennlist.com/webercarbs ----- Original Message ----- From: "Hans E. Hansen" <FList [at] hanshansen.org> To: "Larry Turner" <l02turner [at] comcast.net> Cc: "The FerrariList" <ferrari [at] ferrarilist.com> Sent: Wednesday, March 26, 2008 4:40 PM Subject: Re: [Ferrari] All about oil???? > OK, here is the article that I mentioned in the previous post. > > BTW, AEHass' arguments *may* be right, but given a choice, > I think I'd rather trust the Ferrari engine designer over an amateur > arm chair automotive engineer. The gist of his arguments, if I > recall correctly, is that all you need is 10psi/1000 rpm and that > anything over that is overkill, causes excess friction/heat in the > oiling system, etc. > > However, consider: Suppose you attach a massive oil pump to > your engine. Think irrigation pump. You could run just about > any fluid - water, gasoline, acetone - and maintain 10psi/1000 rpm > or better. Would you really want an ultrathin fluid lubricating your > engine's innards, even if it were in gusher quantities? > > I've always thought that the viscosity of the lubricant should match > the clearances of the parts. Most gears use thicker oil/grease > because they don't necessarily mesh tightly. Some precision > gearsets do, however, and they are lubed with a much thinner > oil. Back a few decades ago, Smokey Yunick specified some > quite loose clearances for his NASCAR engines, and he ran > 50w to help "fill the gap". I think that now days the latest thinking > on this subject is to build racing engines with much tighter > clearances and use a thinner oil. It's my understanding that > modern F1 engines use oil about the consistency of gasoline, > but their bearings have near zero clearance. > > A few decades ago I worked on an injection pump for a diesel PU. > The entire apparatus was lubed by the fuel itself. But the > clearances for most of the parts were just a few 1/10,000 's. > To get the piston into it's cylinder, you had to cool it with > freon to shrink it slightly, otherwise it was a real bear to line > it up so it would go in. Again, tight clearances, thin lube. > > According to my 308 service manual, the rod bearings are > clearanced in the range 0.046 to 0.089mm with a 0.120mm > wear limit. As all my past engine work was in inches, let me > convert: approx 0.002 to 0.0035 inches, 0.005 limit. > These, to me anyway, are not real tight bearings, especially the > upper assembly limit. This is about the outside of the range of what > we would build a small block Chevy to. In particular, the outside > wear limit seems almost huge. I don't think I'd like oil that had a > real thin film thickness in there, regardless of how much of it the > pump was supplying. > > Hans. > > On 3/26/08, Hans E. Hansen <FList [at] hanshansen.org> wrote: >> Peter: >> >> I see what you're saying. But it certainly is difficult to second guess >> the Ferrari engineers. However, charts that I've seen on actual oil >> viscosity measurements seem to converge a bit at elevated temps. >> ie: at room temp there is a big difference between the flow rates >> of a single weight 20w oil and a single weight 50w. But at high temps >> the difference isn't as great. Other than efficiency issues, tho, I >> can't >> see what the harm is in using the thicker oil, as long as the 1st number >> is low enough to allow decent flow at cold temps. Ferrari's 10w50 >> recommendation would seem to have that covered. >> >> Jeff, Matt: Wasn't the zinc/phosphorus issue tossed around here >> just a while back? Or maybe it was on another car forum. Anyway, >> I have kicking about an excellent article about that, and some >> suggestions >> for additives. There is a company distributing the pure ZDDP additive. >> Seems the real issue is cam wear with flat tappets (ie, not roller >> lifters), >> however, I suspect that the additive is a good thing to have for cold >> starts for those of us with carb'd engines, as there is considerable >> raw gas washing the cylinder walls. I'll dig around and attach the >> article and product sources. >> >> Paul: Sounds like your car runs (temp-wise) like mine. In winter, >> the water only gets to about 150ish, and the oil doesn't (or just >> barely) moves off of the peg. I've thought about replacing the oil >> temp sensor, but I'm not sure it is faulty. In hot weather or on the >> occasional track day I do see temps like what you would expect. >> >> >> Hans. >> >> >> On 3/25/08, Peter Pless <ferrarilist [at] pless.com.au> wrote: >> > That all makes sense Hans...BUT...what if ferrari wasn't really >> > concerned >> > with what happened at 212 deg, but more what happened at 260 deg on a >> > very >> > hot day or on the track? Which if the reality is that the 50 mineral >> > oil >> > drops to the same thickness at that temp as a 40 synthetic? That's >> > really my >> > question. Is it possible that 50 is thicker than ferrari would like in >> > a >> > perfect world because they had to protect the engine at 250+? >> > >> > Does that make sense? >> > >> > ---------------------------------------------------------------------------- ---- > _________________________________________________________________ > To unsubscribe or modify your subscription options, please visit: > http://lists.ferrarilist.com/mailman/options/ferrari/l02turner%40comcast.net > > Sponsored by BidNip.com eBay Auction Sniper > http://www.BidNip.com/ > and F1 Headlines > http://www.F1Headlines.com/ > _________________________________________________________________ To unsubscribe or modify your subscription options, please visit: http://lists.ferrarilist.com/mailman/options/ferrari/ferrarilist%40pless.com .au Sponsored by BidNip.com eBay Auction Sniper http://www.BidNip.com/ and F1 Headlines http://www.F1Headlines.com/
- Re: All about oil????, (continued)
- Re: All about oil???? Hans E. Hansen, March 26 2008
- Re: All about oil???? Hans E. Hansen, March 26 2008
- Message not available
- Re: All about oil???? Hans E. Hansen, March 26 2008
- Re: All about oil???? LarryT, March 26 2008
- Re: All about oil???? Peter Pless, March 28 2008
- Re: All about oil???? Doug and Terri Anderson, March 29 2008
- Custom Wheels David G. Cole, March 26 2008
- Re: Custom Wheels jimshadow, March 26 2008
- Re: Custom Wheels David G. Cole, March 27 2008
Results generated by Tiger Technologies Web hosting using MHonArc.