Much more oil data (a lot more)

The manual for my BB512i calls for Agip SINT 10w50, which is a synthetic oil. I can't find a 10w50 weight oil anywhere. What would you guys suggest, 10w40, 20w50 or 10w60?

 

I've only had the 308 for a bit over a month. In general, at operating temp, I don't think I am seeing 10 psi/ 1000 rpm. With only 22k on the clock, I am hoping that is the old sender and not the engine.Where is a good place to buy a new sender..
The oil pressure gauge occasionally wants to be tapped to wake up in the morning - Is this typical of italian gauges?? It otherwise seems to function normally.
I have heard of oil filter prices being high and sometimes astronomical but does anyone have any data or info on oil filter quality?

thanks,
chris

 

chris -- do a search here and at the old FChat site on "Baldwin" -- should get you all the relevant oil filter discussion.

 

I don't understand why RedLine 5W20 and 5W30 did not make your short list. These oils have low startup viscocity (55 and 65) similar warm viscocities (9.5, 10.2) and better hot viscocities (3.3 and 3.8) than your picks.

 

And there is nothing from Amsoil???

 

While I agree with you statement for general purpose road cars;

You are forgetting my application: I spend 1/3rd of my accumulating miles on the road race track, so 100dC is my temp of the oil at startup (15 times per day, once per day at 50dF), and 150dC (realistically 265-280dF on the guage) is my operating temp on the track. I would think that this indicates that the higher 150dC numbers would be usefully better as long as the cold (40dC) numbers are not overly high.

 

I went to Dennis McCann for my sender was about half or 1/3 what you could pay elswhere. 54 bucks I think. I have seen them for up to 150.
When you get to replacing it I have a suggestion on how to with out removing the filter housing OR large oil hoses.
I think it is Allferrariparts.com

Great Guy!

Go with Baldwin or UFI as they have the best back flow and least amount of problems such as element breakdown.

I had used the Fram for a whil until I heard all the horro stories about elements coming apart.

I get my baldwin for like 15 bucks at a local Freight Truck supply company. You know the B 253 I think it is is probly a tractor filter too! The UFI can be pruchased from your local Ferrari dealer for a little more and has the Horsey!

 

Thanks steve and randy. I'll give dennis a call. I bought the koni bushings from him, ($20 each and "a lot" of fun to replace!!!)

 

Wasco: I'd be curious as to how you do the sender switch w/o removing the filter adapter. I was able to get my old one off, but the new replacement is a different design, and I couldn't figure out how to put a wrench/crow's foot/crescent wrench/hammer to the hex portion to tighten it.

 

Yes mine was diff. than the one I took out. The one I took out had a reducer to accomidate a smaller dia. sender.

I know I may get crap for this but what I did was purchase a small needle nosed vice-grip set of pliers to get the final torque to tighten. I was able to use a 11/16? open end wrench to get it almost tight. I think I used one of those stubby wrenches. I believe I took off the crankcase ventilation tank? separator? and I had already removed the coolant hose and pipe in the valley, as they were keeping me from getting the full throw of the wrench. I really think you could use the small pliers to torque without removing anything but yes you do cause a little unoticable damage to the nut on the sender. So let me have it!

It really was no problem and no oil leak.

 

Crap. Why didn't I think of that.

 

Ok I have new Mobil One 20 50 oil and new UFI filter and it is running good pressure. Never below the 10 1000 rule of thumb.( always 80 lbs or above for any RPM above 4 k ) I just know that within several weeks the oil will start to lose pressure at higher temps. I think it is breaking down. I know this cant happen this soon but the Castrol just wasnt holding up. I will post again with my results with M1.

 

Well, based on Ali's previous statememts and recommendations, it would seem that a 5w-40 or 0w-40 would be appropriate....assuming your hot (operating) oil pressures are in the proper range with said oil. If the pressures are too high, you might be able to drop to a 0w-30 or 5w-30.

 

I'd be surporised if it is actually breaking down.

However, new oil does pick up and hold the particulates the settled to the bottom of the pan from the last batch. These microscopic particles will reduce the viscocity of the oil. The easiest solution is to change the oil, run 100 miles, and change the oil again. If the oil is darker than caramel after 100 miles, change it a third time, until all the particulates, varnishes, and gum have been removed. (The intermediate batches of oil can be dino juice).

 

I've been doing som research and ran into the following:

http://www.synlube.com/viscosit.htm

While this guy seems to have an "angle" on various topics. Take this with a judicious amount of sodium chloride. This seems to be the kind of information needed to actually choose an oil for your Ferrari based on how you drive it. I quote several paragraphs from the link:

Now we see a subtle contradiction for our useages of Ferraris. One might expect that the high RPM high load at a track would require a high viscocity oil. Yet Ferraris come with oil coolers, so that the oil temperature stays in reasonable bounds thereby NOT requiring thick oils, and the viscocity required at 8000 RPMs is actually LOWER than the viscocity required at 6000 RPMs (typical american V8) due to the hydrodynamic effects.

What would be ideal would be for the last table on that page had a column for oil temp and a recommended viscocity.

Until then, we revert back to AEHass general premis that the oil viscocity that results in the lowest oil temp is the correct one to use.

Final note: I ran into a different url that indicates that 85% of startup wear occurs due to acid byproducts of combustion not being absorbed into the oil surfacant until the oil thins out towards working viscocity. This acid then etches the rings and combustion chamber and cylinder walls until removed by the oil neutralizers. This is why thinner oils reduce startup wear.

Enjoy.

 

I'm going to go of on a tangent for 8 or so entries in this thread, so let me pack these together.

I took AEHass supplied data and threw it into eXcel then graphed same. The first picture shows the viscocity as a function of temperature for the entire dataset of chosen oils. I have colabled the temperature axis in both centigrade and Ferinheit.

There are several prominent features: A) the general slop of the lines, B) the bunching of oils by the weight, C) the pattern for each type is "well defined".

The general slope of the lines is determined at how fast the viscocity thinnes as temperaure increases. I graphed this on an exponential axis to find the exponent of slope. more data points for each oil would allow one to determine the relationship in a more precise manner.

 

This next picture shows the basic viscocity bands that can be found through these numbers.

 

Since Ferrari recommends 10W40 for my F355 and teh closest weight in these more modern oils is 5W40; let's look at the 40 weight oils from my list.

I have a pointer toward Shell 5W40 oil and Mobil1 5W40 oil. The shell oil is the recommendation by Ferrari. Mobil 1 is the closest line of the same shape that has data at 150 dC, so I am using the mobil data as the extrapolation function for what kind of viscocity the F355 engine needs.

At a race track the oil gets much hotter than cruising down the highway. How hot is too hot; I have heard numbers from <this oil> will take 300 dF without break down, but certainly more than 250 dC is reasonable. With this in mind I placed a marker at 285 dC that is less than the oil viscocity.

It just so happens that his comes out to 4 cenitStokes. So the F355 engine needs 4 cSt of viscocity at the pressures the oil is pumped around for the enigne wear to be acceptable. We will come back to this point later.

 

Now with this in mind, are there any 30 weight oils that will allow the engin to wear at an acceptable rate: let us see:

 

Now let us look back at more normal operation. My car cruises down the road at 185 dF on the water guage and 175 dF on the oil temp guage at 80 MPH in 90 dF temperatures. I rounded this up to 200dF oil temperture and placed a similar marker. It just so happens that this marker is placed at 10.7 cSt.

As described in the extracted post from the oil expert: the ratio of viscocity at 285dF (4.0) and at 200dF (10.7) is 2.65:1 that is the viscocity is 2.65 times as thick at 200dF as it is at 285dF.

 

Now let us consider models for wear. Wear might be quadradic and the wear rate might quadrupple when the RPMs double, wear might be cubic and go up 8 times four a doubling, or wear might be exponential. My argument dose not need to choose which, since in the region of import the cubic and exponential curves are of similar magnitude.

Let us say that the Ferrary engin designer chose 4.0 cSt as the wear rate acceptable at 285 degree oil tempertures and deliver an acceptable life (say 10K miles--the rebuild life of a challenge car operated in racing conditions). This model says that if that car were operated at 200 dF oil temp, that wear would be progressing at only 1/7.8 times as fast per RPM, and since the RPMS at cruise at closer to 1/3 red line, the wear rate of the engine about 1/23 or 4% that of the same engine in challenge conditions. And thereby should last 200,000 miles.

<<Well at lest the order of magnitude is believable>>

 

Now lets go back to modern oils. This first picture shows the typical cures, while the second shows an abnormal curve. If it weren't for the mobil 1 15W50 data points I would have doubt on the accuracy of either the 100dC data or teh 150 dC data for the redline oils. But with the Mobil 1 datapoint, There is agreement that these oils can be built.

With these special viscocity imporved oils, one can run 10W30 and 5W30 oils at the race track with the same engine wear rate as the originally specified 10W40 oil formulation. BUT NOT WITH ANY 5W30 or 10W30!!!

If we can agree tha 4cSt is enough for good wear rate properties, and we go back and look at the wear rate graph, A good wrap to red line with the oil at 200dC does 1/7.8 as much wear as the same wrap to redline at 285dC. So, as long as the oil temp is undercontrol, the wear rates on these engines will be small.

Since the F355 challenge cars have a second oil radiator and more oil, they are notorious for being cold blodded, and have a pretty good service life for the application they are put towards.

Does anywon know the operating temperatures of a F355 challenge car on a hot day after a goodly long run in capable hands? And how these might relate towards 360 Challenge cars?

 

It seems to me that any viscocity bigger than 10 cSt is unnecessary, thereby the drive to lighter starting weight oils is reasonable.

Disclaimer: I'm just interpreting the data, and applying reasonable models to a difficult problem; your milage may vary, no engines were hurt in the production of this diatribe.......