I'm running a vented catch can on my TII and it didn't seem to help any.

 

Is anybody running 15w40?

 

haha - I totally agree. Run w/e oil you want, just change it frequently.

If anyone is still interested, read the article I posted above from Ferrari Chat. Here is a teaser....

Here is a quote in part from comparing mineral oils to synthetic oils, and behaviors of oils at different temps.

AE Haas, motor oil 104 (part four):

"As it turns out synthetic oils do cling to parts better as they have higher film strength than mineral oils. Synthetics are thinner overall. They have greater slipperiness. Yet they stick better to engine parts. Again, this concept is the opposite of normal thinking.

The thickness of moving oil is measured in centiStokes or cS. Most engines want the oil viscosity to be around 10 cS at normal operating temperature. The really thick multigrade oils have a viscosity of 20 cS at operating temperature. One is not twice as thick as the other, it is only 10 cS thicker.

As we increase the heat from 212 F to 302 F the most commonly recommended oil thins from 10 cS to 3 cS. The thicker oil drops from 20 cS to 4 cS. Note that in a very hot engine the difference between the two oils is now only 1 - 2 cS. In other words they have about the same thickness. There is little advantage to a thicker based oil as a 20W-50 at very high temperatures. No, the 4 cS oil is not twice as thick as the 2 or 3 cS oil. This difference is almost insignificant.

There is a huge advantage of using the thinner, 10W-30 at startup where 90 percent of the engine wear occurs. At 75 F the thicker oil has a viscosity in the range of 250 cS while the thinner oil has a viscosity of 100 cS. The thicker stuff is 150 cS thicker. This is a very big difference. I am using the 20W-50 as my thicker oil example here."

Synthetic oil:

Oil type...Thickness at 75 F... at 212 F...at 302 F

Straight 30...........100...................10...........3
10W-30.................75...................10........ ...3
0W-30...................40...................10...... .....3

 

perhaps Rich can comment on this, the vented oil pan makes some sense, I'm not sure how an oil catch can would improve the situation

one thing that definitely does help is to take the car for a nice long freeway cruise, stay out of the boost, keep the AFRs at 14.7 or higher, and burn off some of the excess fuel in the oi

then again, how many of us are going to do THAT?

 

speaking of a "brick"...for the 50th freakin time, any oil in these engines quickly loses a viscosity grade because of the fuel dilution, THAT is why most knowledgeable people here are running it, so cease and dissist with the tired ferrarichat link already, sheesh, we got it!

 

That is the most obvious point and you have repeated it so many times I can't count them. In a discussion, it is important to be able to be open- minded and interpret new information that comes in.

You could of just started the thread like this:
"I think 20w-50 is the only oil to run in an FD. And if you understand anything, like I do, you will use this oil. Any questions?"

The blanket statement "it is crazy to use 10w-30 in Rx7s" is just plain wrong. If 10w-30 gives you the appropriate oil pressure, use it. When/if that pressure drops, change it. Or change it at 2k miles.

 

http://www.bobistheoilguy.com/forums...76#Post1335676

 

An accurate oil pressure gauge is a useful diagnostic tool, sure, but we've already seen evidence that 30w loses a viscosity grade with only 1,000 miles...I don't know about you, but I'm not about to change the oil every 1k miles, I drive the car year around, it's not a garage queen

btw, your previous post, prior to editing, stated "you might be right" and left it at that, just for the record

 

I'll take this guy's word over just about anyone on the forum, aside from Howard

 

yeah i do i posted this b4

here is what i run in my FD after much research :
Shell Rotella T ( For Diesel ) [ 15W-40]

http://www.shell.ca/home/content/ca-...ella_data.html

Among other things :

Pour Point, ° C -40
Flash Point, COC, ° C 229
Phosphorous ppm : 1260
Zinc ppm : 1380
Calcium ppm : 3690 ( Good for the rotary bone )
Viscosity Index 139 ( >110 ==> VERY HIGH = not too much viscosity change with temp increase )
Sulphated Ash, %wt 1.0 max

 

Sounds good, have you been running this for a long time now? I think I'll try this next.

 

~ 7xxx km`s

i chose it because :
viscosity is in the range i need
has the necessart aditives ( ZDDP )
Viscosity index is excellent
It has the SAE rating SH +
conceived for diesel = for very dirt environment ,
and all the other stats listed on the site

 

Have you done an oil analysis yet?

 

no i want to send this sample out
just had no time

first 2000 km wew a flush and transition from roay purple , and the next 5 k is what i will send when i have time

 

be careful what you ask for

 

sure, but that's a 100% drag car where all that matters is ultimate hp and elimination of any and all parasitic losses; it probably gets torn down after a few runs...I severely doubt Howard is going to recommend 5w-30 on a street car that goes 2-3k between oil changes

 

the guy runs high HP engines, but told Howard to use 5-30 in his engine. Here is another thread of howard telling another guy with a street car to use 5w-30
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/what-oil-my-93-rx7-bnr-stage-3-turbos-515292/

 

I have some of this in my garage, and I wasn't sure what to think when I saw you using diesel oil in your car. I admit it, I might have scoffed at the idea. But your post prompted me to read into that a little.

The short answer is that for a petrol piston engine, the level of detergents in a diesel oil is too high. The compression levels are so high in most piston engines that the clean-burning formula of a diesel oil is not sufficient. It also has plenty of anti-foaming agents not needed in auto engines.

However, it seems to be a good fit for our needs - it's clean burning and there is no such thing as "too clean" of an engine. The Shell Rotella is also affordable at $20/4qts. There remains the question of what it does to catalytic converters, which diesels don't have. Many additives out there are not good for cats.

It begs the question exactly what is in the Idemitsu that makes it most suitable to rotaries - perhaps it's more similar to diesel oil than regular oil?

Dave

 

Very good point on the cold start wear and tear. I used mobil 1 10-30w when I got my car, and now I am using RP 10-30w, but now I am looking to switch oils. I am very interested in trying Idemitsu since its made for our engines but really don't feel like ordering and waiting for it so I may go with the Rotella oil someone posted up or maybe castrol gtx.

There is nothing we can do about this fuel dilution that I know of, it's something we gotta live with.

With the average 3% fuel dilution, the rotella oil should still be above a 30w oil by 3k miles. It's thinner then the 20-50w oil and just a tad thicker then the 10-30w oil but cold starts should deliver the oil quick enough and with the fuel dilution it should hold up just fine

 

I just picked up a gallon of shell rotella t 15w-40 for 12 bucks at walmart.

 

^ xacly it`s cheap , and good
and ... about the effects on cats .. i dont really care for that , i have no cat at the moment and .. ill install a high flow cat soon

 

I don't smell fuel, but the oil is the thickest sludge I have ever seen in my life.

 

So I take it you can get this at any walmart? where else would 1 be able to find this delicious oil?

Wish you could check out online what type of oils walmart has...

 

hey do you have a bigger picture of that avatar, afgmoto?

 

Yep, just go to the oil section and it should be there. All the diesel oils were together in a corner.