Oil Circulation Systems-old vs new (70 911T-77 911S)

[CRH911S]

I am rebuilding the front suspension and brake components on my car and decided to remove the oil lines for close inspection and cleaning as well.
To make a long story short I ended up removing the entire oil line system, tank and engine forward. Before starting this task I envisioned having to replace the long return line and thermostat. Now that I have everything apart it looks like I'll end up replacing the thermostat, feed and return lines.
Yesterday I attended a auto-x and there was this guy running a nicely restored 1970 911T. Knowing that early 911's don't have the same oil circulating systems as the later cars I checked his and it didn't. After his next run I introduced myself and inquired as to the oil temperature-120F. I'm not that certain if this was an accurate reading or not but i'm not surprised because even in my car with the loop cooler it hardly reaches 180F and this is on long drives at sea level at or above posted speed limits at approx 70F.
I am trying to decide whether or not to backdate the oil circulation system due to cost concerns. What do you guys think? The car will only see PCA auto-x and SCCA Solo-II events only.

[911pcars]

Let me get this correct. This fellow says he's running at 120ºF? You're running 180ºF and you want to use his system?

His temperature gauge is not working correctly. 180 is fine. Keep your system.

You are now $1000 richer.

Sherwood

[Grady Clay]

Clinton,

I would restore the oil system to original as best possible. It will help maintain the originality and value of your '77 911S.
Unless the long pipes are badly crushed or crash damaged, they are probably repairable. It might be prudent to replace the flex hoses. The thermostat, with its aluminum threads, is probably expendable.

You may want to take a cruse to Seattle and a nice trip down the PCH to San Diego. Participate in a few West Coast events on your way? You will appreciate having the proper oil cooler or better.
A trip across the high desert or in the high mountains will demonstrate the necessity for all the cooling possible.

Your ’77S and the ’70T have functionally the same oil systems with the exception yours has the additional front cooler (similar to a ‘70S) – very desirable. There are many subtle differences in the plumbing such as pipe size, fittings, coolers, etc.

I suspect the ‘70T owner meant to say 120C not 120F.

Best,
Grady

[CRH911S]

Thanks in advance to all responses. I am faced with having to restore the current system at an expense that I wasn't anticipating. I was hoping to hear from the early 911 owners and the efficiency of the older systems. What I tried to say in the original post was that the car is purpose built for auto-x and auto-x'd 10-12 times per season. The average temperature here in Anchorage, during the summer months, is probably in the 60's. Lately it's been in the low 80's but this is unusual. I was thinking that if I could keep the temperature below 200F then this is something, I think, I could live with and get away without the expense.

[chuckw951]

Your signature line states that you are running carbs and E cams. If the induction system isn't original then why worry about using original oil cooling parts.

But before you get to that decision you have to determine if there's anything wrong with what you are running...

Otherwise just clean up the stock parts and bolt'm back on to the car...

Do you have the 11 blade fan upgrade? Have you tossed the thermal reactors? From what I understand about the 2.7 cars these are two upgrades needed to beat the heat.

[MAS]

Your car's oil cooling sounds more than fine as is. I wouldn't worry.

If it starts running too cool... you'll not reach the proper operating temperature as often as you should.

Also, 120 F cannot be the proper operating temperature of the earlier car (if it was actually warmed up).



-MAS

[CRH911S]

For starters there was nothing wrong with the existing system. I decided to remove and repair the return line that was somewhat crushed at some point in the life of the car. Functional but I didn't like the way it looked.
As it stands now the system is apart, which was a PITA. My concern has to do with the condition of the threaded components. For example aluminum imbedded, solidly, into the threaded portion of the brass coupler that threads to the t-stat. As it stands I can't use the tank to t-stat line. Or the t-stat for that matter.
I will probably end up replacing everything that is needed the way that it was but the purpose of my post was to hear back from the owners of 911's as to the efficiency of the older systems.
I was born and raised in So. Calif. so I know what heat and smog is. Anchorage has neither-the average summer temperature is in the high 60's.
Feedback is apprectiated in advance.