Vents in the bumper, really lower oil temps?

[RC70SCoupe]

I have been considering putting vents in the bumper similar in the picture to try to
lower the oil temps. The battery box is in place.

Do these "really" do the job or for looks only?

[steve shea]

If a front oil cooler resides behind the vents, then yes.

[boxster03]

Before you modify you might want to get some basics - I think from your profile Ray you are talking about either a 70 or 72 S ? Since both should have the front oil cooler - what temps are you running ? Is this regarding tracking the car or just normal ops ? I know on my 70E when I was running too rich and the MFI wasn't dialed in I ran much hotter particularly at higher altitudes and sustained speeds - maybe 230+ After getting the MFI dialed in and new plugs (same oil) I never ran over 210 and that was maybe doing 110-120 for 10 miles or more at 9,000 plus feet on a hot day - What plugs are you using ? Oil ? MFI dialed-in? throttle boddies in good order ?

[jameshtaylor]

Ray,
This long wandering thread below pretty much summarizes my quest for more air/cooler oil. If it bores you to tears, just skip to close to the end and find my conclusion that 20+ sq inches of air ducted to the cooler, no fan, will get you 20°. I doubt that a solution like the one in your picture would have done much for me. But a lot depends on how you use your car and how many degrees of cooling you seek. For all I know a fan and a few little holes would do a great job if all you do is freeway/city driving. I see after writing this that your battery box is still in place. That makes a serious attack on cooling awfully difficult short of a (center) front bumper solution.
Jim

http://www.early911sregistry.org/for...ooler+air+flow

[RC70SCoupe]

Guys, thanks for the replies…
I should have posted more info..

Its for the 2.9 twin plug, MFI. Its dialed in as good as it gets. I also have modern A/C. The stock 1970 911 S oil cooler is in place behind the battery box. Normal operating oil temp is 190

However, when the air temps hit over 90 at the beach, I want to use the A/C. Thats when my oil temps start to climb over 230-40ish..Thats when I turn off the A/C. Oil temp settles back down to 210. I am also spending more time in the desert.

Just wondering if I could place a few vents to really help out..Install a second cooler behind the drivers side battery box, change the front bumper to a cooler in the front..

James T., I did read your entire thread. Thank You. I now realize that no matter which option I choose, I need to have the ducting in place to the cooler.

[RSTarga]

You need a fan on the cooler. The vents won't help in traffic with A/C on.

[911pcars]

Ray,
In traffic, there's almost nil aero air flow through the grill. The heat absorbed from the cabin, then radiated from the condenser, is an engine killer. At low vehicle speeds with A/C ON, the engine is essentially cooled with hot air. There's only one condenser in an early 911 and it's in the cooling air path. A secondary condenser in the front (as in later 911s) or in a fender w/fan would help.

A/C was essentially an afterthought in our early cars. A better engineered system appeared years later.

As a WAG, in addition to increasing oil cooling capacity, I'm theorizing a condenser fan or two pushing air upward at speeds up to 5-10mph might help heat transfer, especially to redirect heated air away from the engine in traffic. Once at speed, the fan would either shut down or reverse flow to assist airflow through the condenser. This idea might have been attempted at some point in history and then discarded.

Once upon a time on a family car trip, this was my primitive solution to a sporadic A/C system in 100ºF weather. Swamp cooling at its most elemental:

Sherwood

[Paul Rodelo]

Ray,

Not only do you have an engine hotter than factory spec, you are running aftermarket A/C.
The factory oil cooling system is insufficient as you are referencing.
Remember my old 930 RSR? (see pic)
Although it did not have A/C, it did have the modified 3.3 turbo engine.
I had Steve Alarcon set me up with the center cooler system and it never ran hot, "ever".
The current owner of the car never complained of heating issues and the car was often raced on the track.
Thing is, the center oil cooler will help you cool your oil temps, but that will not mitigate the hot air passing the condenser.
That hot air is pulled through the deck-lid, passed the condenser through the engine cooling fan, over the cylinder fins.
I would also like to have A/C in my 70 911, but will have to see what can be done to relocated the condenser under the deck-lid.

See you tomorrow at Scott's

Paul Rodelo