| Author |
Message |
Edward G. Salla (350hpmondial)
Junior Member
Username: 350hpmondial
Post Number: 61
Registered: 2-2002
| | Posted on Thursday, April 04, 2002 - 6:59 pm: | |
Rob,
Thanks for the compliment. I have worked in an oil analysis lab as a tribologist. ( i.e. one who studies friction) I thought I was going to make it, but my car has developed a leak in the inlet manifold plenum to #6 cylinder. It runs great on boost because it blows, but with the throttle closed, when inlets are at vacuum (sucking) I'm getting a miss. (really sucks)
Thus, I am not dyno ready.
I have been reviewing your thread about plugs missing, and will check all plug wires. ( My timing light is back in Denver.) I will be pulling each wire to check for an additional miss, unless somebody here in Dallas with a timing light wants to come over Saturday for a brew and garage day. (It's gonna rain anyway, so it's a good day to hang out in the garage.)
Worst case, I will be pulling the inlet manifold and fixing the leak. (I need to paint it anyway, yours looks great.)
Best case, I will discover a simple ignition wire or plug problem and be dyno ready. |
Rob Lay (Rob328gts)
Board Administrator
Username: Rob328gts
Post Number: 1391
Registered: 12-2000
| | Posted on Wednesday, April 03, 2002 - 9:51 pm: | |
Man, Edward's experience in 8 different engineering fields is showing.
Ed, are you doing the Norwood dyno day on 4/20? |
Edward G. Salla (350hpmondial)
Junior Member
Username: 350hpmondial
Post Number: 58
Registered: 2-2002
| | Posted on Wednesday, April 03, 2002 - 6:58 pm: | |
Oil viscosities "weights" have little to do with the bearing wear experianced upon cold start ups. That is why high pressure lubricants (borates and lithium compounds) are added to the blends.
The new API (american petrolium institute's) SL/CF specs are the most stringent set of specifications published to date. Lucky for us, oil companies make little profit from marketing engine oils. They keep raising the bar to push the little manufacturers out of their beloved business.
If the oil you are using meets the CF specs, then you are light years ahead of the old (but not so old) SL/CE specifiactions.
If you read back in this string, Rob is correct with two out of his three assumptions;
"heavier oil offers no benefits over a lighter weight oil. And, it adds friction (fluid friction) robs HP (1 or 2 HP)" But all oil will eventually seep out of your bearings, after the crank and rods are acted on by their ultimate enemy.......... Gravity.
We need frictionless bearings made out of superconducting material, then replace your oil with liquid nitrogen.
In theory, a cooler combustion chamber temp (approximately -460 deg F) would allow a higher compression ratio, thus more HP. But, a lower high temp in your cylinder would subtract from your overall engine efficiency, lowering HP. Alas,,,,,,,,,, another compromise.
,,,,,,, or ,,,,,,,,
We need to dig up the decayed body of Dr. Brayton and ask him (it) to rewrite the 2nd law of thermodynamics. ha ha
Conclusion, never shut off your engine, drive your work of art untill you can't see anymore taillights in front of you. Redline it in each gear. Smile and wave at all toyota supras, who can keep up,,,, but, alas, they will never sound like an F car. But, eventually you will need to replace your valve guides. (Note; valve guide friction reduction technology relies upon metal to metal friction factors for little oil is allowed to get inside of them.) |
Steve (Steve)
Junior Member
Username: Steve
Post Number: 130
Registered: 2-2001
| | Posted on Wednesday, April 03, 2002 - 4:04 pm: | |
If you really think about it don't we all change oil at around 1500 to 3000 miles? If so I would think that we use the book recommended (77 308GTB) oil which I think is 20-50W Syntech Aquip or even Mobile 1. I know the oil I drain out looks pretty clean and I tempted to use it in my daily commuter. |
Paul Newman (Newman)
Junior Member
Username: Newman
Post Number: 117
Registered: 12-2001
| | Posted on Wednesday, April 03, 2002 - 1:48 pm: | |
I dont think either one will destroy the engine. These cars dont see cold weather either so I wouldnt worry. Using a 308 as an example, they have a bullet proof bottom end compared to late model domestic crap, yet we (or some of us) drive away in the winter without warming up our engine. It doesnt seem to hurt them. I guess Im trying to say that a Ferrari engine isnt a weak piece of crap that cant take cold oil and load without self destructing. Let it idle for a few minutes and away you go. Beat on it when it warms up. |
Ken (Allyn)
Member
Username: Allyn
Post Number: 275
Registered: 10-2001
| | Posted on Wednesday, April 03, 2002 - 1:06 pm: | |
Experts say not to idle more than 30 seconds; better to drive slow. Then the Ferrari owners all idle 5-10 min in the cold so as not to stress a cold engine. I idle my Lotus 2 min. and drive in as low rpms as I can without chugging until the temp gauge moves. So PLEASE! What's the story??? |
Frank Parker (Parkerfe)
Member
Username: Parkerfe
Post Number: 759
Registered: 9-2001
| | Posted on Wednesday, April 03, 2002 - 12:56 pm: | |
My 1994 348 Spider calls for 10w40 oil. I have been using 10w60 as I have several cases of it for my 2000 M5. |
Rob Lay (Rob328gts)
Board Administrator
Username: Rob328gts
Post Number: 1390
Registered: 12-2000
| | Posted on Wednesday, April 03, 2002 - 9:53 am: | |
I'm not sure I follow not letting it idle at first? The fast idle will take the RPM's to 2-3k for several minutes anyway. What are the advantages of driving at the same RPM vs. idling? I would think driving would be worse, because can you really keep it right at 2-3k? |
Christian (Christiank)
Member
Username: Christiank
Post Number: 304
Registered: 1-2001
| | Posted on Wednesday, April 03, 2002 - 1:27 am: | |
Unlike some people I think it/s most important NOT to let the engine run at idle for a few minutes. Start it up and drive slowly away at about 2,000 to 2,500 rpm. A good engine oil helps a lot, I think any good oil 10-40 or 15-50 meeting Porsche, BMW or VW requirements is good enough for our "old" cars. |
Richard Stephens (Dino2400)
New member
Username: Dino2400
Post Number: 49
Registered: 10-2001
| | Posted on Tuesday, April 02, 2002 - 10:46 pm: | |
"One reasonable argument I've heard that sounds reasonable is anything from 100C to 125C is a good running temp. You want it to be over 100C so that water is shed from the oil (in the form of steam) through the vapor control system."
Thanks Ric. That makes sense. I was just thinking that I'd have better oil pressure if the oil stayed cooler. BTW, Vapor control system? Oh, you mean those two hoses coming out of my oil filler necks that are vented to atmosphere? Ha! In my case it's the vapor "uncontrol" system I guess. ha! |
Paul Newman (Newman)
Junior Member
Username: Newman
Post Number: 115
Registered: 12-2001
| | Posted on Tuesday, April 02, 2002 - 7:42 pm: | |
I dont see any advantage to running a thinner oil during breakin because the rings are what you are breaking in not bearings. I would use a non-synthetic oil during the break in period then switch to synthetic. This allows the rings to seat which is the most important part of break in. I think the best situation would be if someone rebuilt their engine, changed the clearances and ran synthetic 5w20. It would have good oil control and more power as well as lower emissions + better fuel economy. |
Timothy J. Dressel (Tjd)
New member
Username: Tjd
Post Number: 48
Registered: 4-2001
| | Posted on Tuesday, April 02, 2002 - 7:28 pm: | |
Would it be ok to use oil lighter than 20-50 for the first few hundred miles during break-in, if one didn't drive the car to hard or hot? --tim d |
Paul Newman (Newman)
Junior Member
Username: Newman
Post Number: 114
Registered: 12-2001
| | Posted on Tuesday, April 02, 2002 - 7:09 pm: | |
TJD, I would be more concerned about rod bearing life with a thin - water like oil such as a 5w. The cams should be fine. Also oil control might be an issue with the extra throw off from the crank pins.
Steve, you are right but going from a 50w to a 30w is a big difference that you can feel when you touch the oil when hot or cold. I wouldnt run a 20 or 30w oil in my 308. Considering the cost of engine repair and the fact that most (Im assuming) rely on a shop or dealer for repairs, I wouldnt experiment with such things unless of course money was no object. All of the new phords I work on require 5w20 and should not use 5w30 like the previous years. Why? What have they done differently? They wont say but there is a difference in feel of the oil so I listen and do as Im told. |
Timothy J. Dressel (Tjd)
New member
Username: Tjd
Post Number: 47
Registered: 4-2001
| | Posted on Tuesday, April 02, 2002 - 6:51 pm: | |
I recall reading, maybe two years ago, about a NASCAR engine builder using 20w (I think it was Mobil1), which allowed, and perhaps also required, keeping the engine cooler than it would otherwise run. I also recall something about saving weight.
My question is, does using less than the specified 20-50 cause excessive wear, particularly on the cams? --tim d
|
Steve Magnusson (91tr)
Member
Username: 91tr
Post Number: 631
Registered: 1-2001
| | Posted on Tuesday, April 02, 2002 - 6:19 pm: | |
Rob -- both the '89 and '91 (US) TR OMs show 10W40 for the engine oil specification. |
Ric Rainbolt (Ricrain)
New member
Username: Ricrain
Post Number: 43
Registered: 2-2002
| | Posted on Tuesday, April 02, 2002 - 5:42 pm: | |
"I'm considering installing an oil cooler, one that would keep oil temp around 80-90C. Any thoughts on the optimum oil temperature for a street car (i.e. one that I'd like the engine to last at least 30,000 miles). I realize this is a controversial topic... (I tried a search but didn't find anything). "
One reasonable argument I've heard that sounds reasonable is anything from 100C to 125C is a good running temp. You want it to be over 100C so that water is shed from the oil (in the form of steam) through the vapor control system. |
Edward Gault (Irfgt)
Member
Username: Irfgt
Post Number: 947
Registered: 2-2001
| | Posted on Tuesday, April 02, 2002 - 5:17 pm: | |
I do not believe that oil temperature is a big concern in a water cooled engine that rarely gets over 240 degrees coolant temperature. My 1965 Corvair wich is air cooled and has a small factory oil cooler does not have an oil temp gauge but does have a cylinder head temp gauge. The thermostat for the engine cooling fan duct doors opens at around 275 degrees. Normal driving at 70 mph will see head temperature at around 425 degrees. With the car wide open and the turbo boosting at around 15 inches mercury you can see temperatures approach 550 degrees. There is a buzzer that alarms you at 575 degrees and at 600 degrees the head temp gauge pegs and there is an aluminum meltdown. What I am trying to stress is that this car was designed in 1965 with the oil that was sufficient at that time and the car has made it and runs well today under those conditions. So, if the oil of yesterday could protect an engine that operates under such adverse temperatures then todays oils should be considerably better used in a car that operates at half the temperature of a lowly Corvair. |
Richard Stephens (Dino2400)
New member
Username: Dino2400
Post Number: 48
Registered: 10-2001
| | Posted on Tuesday, April 02, 2002 - 4:56 pm: | |
The dino motor is an old design so I run 20w-50 Castrol GTX. In my view, it never gets cold enough here to need anything thinner. I must say that the oil temp regularly exceeds 100C and when it does, oil pressure noticeably drops, even with the supposedly thicker "50" part of 20-50W. If the electric oil pressure gauge can be believed (it can't - reads 20psi less with the headlights on!), it's somewhere around 70psi at 5000rpm when oil temp is about 80C and then is 50psi when oil temp goes over 100C.
I'm considering installing an oil cooler, one that would keep oil temp around 80-90C. Any thoughts on the optimum oil temperature for a street car (i.e. one that I'd like the engine to last at least 30,000 miles). I realize this is a controversial topic... (I tried a search but didn't find anything).
|
Steve (Steve)
Junior Member
Username: Steve
Post Number: 129
Registered: 2-2001
| | Posted on Tuesday, April 02, 2002 - 4:27 pm: | |
I'm no oil expert but I was led to believe that the 2 numbers identified the viscosity of the oil in a cold (10 weight) and as it warms up to the final 40 weight . The oil is refined to the 10 weight spec and then the additives allow it to increase its viscosity as it warms up. I also understood that oil "breakdown" was the additivies getting contaminated and the oil would reduce down to its base (like 10w). So besides the bearing clearance issue a lower vis. oil say 5w-30 will start better in the cold but when hot is only a little thinner than say 20w-50. I think thats what I've read? |
BretM (Bretm)
Intermediate Member
Username: Bretm
Post Number: 2106
Registered: 2-2001
| | Posted on Tuesday, April 02, 2002 - 3:55 pm: | |
Don't the 360s use like 5w-45 or something like that. I'm up in the air about this one. After rebuilding the jeep engine I switched to 10w-30 and it runs a little more normal (35lbs of oil pres. as it should, as opposed to 40lbs as it was, when running at idle). On the Ferrari though I think I might stick with the 20w50 I was using before, but switch over to synthetic. |
Rob Lay (Rob328gts)
Board Administrator
Username: Rob328gts
Post Number: 1388
Registered: 12-2000
| | Posted on Tuesday, April 02, 2002 - 1:58 pm: | |
Are there any Ferraris that have a recomended weight below 20w-50? |
Paul Newman (Newman)
Junior Member
Username: Newman
Post Number: 113
Registered: 12-2001
| | Posted on Tuesday, April 02, 2002 - 1:52 pm: | |
The other thing to consider when using thin oil is how the engine is built. Bearing clearances are the biggest concern. If you build an engine with say 5w30 as the intended blend, bearing clearances must be tightend up or oil consumtion will be the result. The excessive oil thrown off the rod and main journals due to large clearances overwhelm the oil control rings causing consumption. Thinner or lighter oils are used on todays cars for fuel economy, power and emmissions reasons. The engine is also designed for it. Bear that in mind before swapping grades on an old Ferrari with mile wide bearing clearances not intended for light oil. I would follow the reccomendations from Ferrari but use synthetic or adress the bearing specs during a rebuild if intending to run something else. It also takes more HP for the pump to move 20w50 as apposed to 5w30 or 20, thats where the losses would be. |
Ken (Allyn)
Member
Username: Allyn
Post Number: 270
Registered: 10-2001
| | Posted on Tuesday, April 02, 2002 - 12:54 pm: | |
Old engines will leak a lot less with 20W 50 than 10W 30. Of course, you should just fix the leaks. |
Rob Lay (Rob328gts)
Board Administrator
Username: Rob328gts
Post Number: 1387
Registered: 12-2000
| | Posted on Tuesday, April 02, 2002 - 12:50 pm: | |
Through learning in my auto tech courses and car racing I've come to the opinion that most of the time, lighter weight oil is better. For example, using 10w-30 vs. 20w-50. The reason being that lighter weight oil has less friction and thus keeps your engine cooler and tests show more HP (1-2%). Like Nick has said, your engine gets the most wear on start up and over heat. Well, the engine is started cold every time, but most engines never reach a critical over heat situation. 10w-30 won't break down at even major over heat cases, if you have been changing your oil on a regular basis. So a heavier oil offers no benefits over a lighter weight oil. It only adds friction, robs HP, and adds cold start up wear. |