Oil cooler ideas for this situation?

Danny_Ocean · 08:57 PM

Although my car is a regular ole' 79 911 under its skin, there are some parts which do not fit due to the body kit, a fender cooler being one of them:

I have a ton of available space in the front fascia, under the "nose". My idea is to install an oil cooler, laying flat with a puller fan on top, in this cavity. Would that be adequate or must the oil cooler sit upright to take advantage of the air flow?

911pcars · 10:49 PM

I think you would get optimum cooling if the airflow goes directly to and is perpendicular to the heat transfer surface. However, "optimum" can be overruled by high velocity/high volume and directed airflow, a large-capacity, efficient oil cooler, fan(s) to encourage air flow at reduced vehicle speeds and an exit passage for hot air. The variables need not be optimal for any particular installation to obtain adequate cooling. However, you don't want to compromise and end up with borderline cooling effectiveness. It depends on the cooling load. 160 NA or 900HP turbo? Street or track?

Sherwood

Danny_Ocean · 04-23-2007, 06:53 AM

Motor is a stock 3.0. Occasional street driving only. Car has only trombone cooler now. I'd like to upgrade before the FLA summer heat arrives.

My theory is the cooling air will be sucked upward by the puller fan while the car is in traffic or idle. As speeds increase, there should be enough air flow moving upward...fan will then kick-off via t-stat switch. There is plenty of room for the hot air to exit...either upward or off to the sides.

1980 911 sc · 04-23-2007, 07:48 AM

MY 2 C...

anything you add will be = to or > than the trombone. Dont forget you have a cooler on the motor itself. Plumbing tubing across the front and back will be enough; like a straightened trombone. An actual finned cooler in any orientation will fine.

IROC · IROC's Garage

I have the Mocal trombone replacement cooler kit on my car and it works great. I installed a 6" Spal fan and it keeps my 3.2 nice and cool on the street (never above 190F). It struggles a bit on the track, but I still don't exceed 220-230F on the track.

911pcars · 04-23-2007, 12:20 PM

"As speeds increase, there should be enough air flow moving upward"

Sometimes you can't presume air will turn where you want it to. You can only try and see how it works. If airflow hits a front-mount oil cooler, it should be fine.

Trombone "coolers" are fine for mild temperatures. However, 230ºF is getting close to too hot.

Sherwood

Danny_Ocean · 04-23-2007, 01:29 PM

Quote:

Originally posted by IROC
I have the Mocal trombone replacement cooler kit on my car and it works great. I installed a 6" Spal fan and it keeps my 3.2 nice and cool on the street (never above 190F). It struggles a bit on the track, but I still don't exceed 220-230F on the track.

Do you have a source for the Mocal kit? I did a cursory search here, but didn't find it.

Grady Clay · 04-23-2007, 02:22 PM

Danny,

Your ‘79SC has a smaller engine cooling fan than most other 911s. It is 226 mm diameter where most others are 245 mm. You already have the large (134 mm crank pulley. Find a late 11-blade fan and housing to get the larger 1.82:1 fan and ratio.

Not only will it improve engine cooling where most important (heads & cylinders) but will even improve the A/C performance.

A front cooler with sufficient heat dissipation capacity to stay in the thermostat modulating range is important also

Best,
Grady

Danny_Ocean · 04-23-2007, 03:48 PM

Quote:

Originally posted by Grady Clay
Danny,

Your ‘79SC has a smaller engine cooling fan than most other 911s. It is 226 mm diameter where most others are 245 mm. You already have the large (134 mm crank pulley. Find a late 11-blade fan and housing to get the larger 1.82:1 fan and ratio.

What year(s) fan/shroud should I be looking for? I'm not sure if/how my car has been modified in the past (e.g. upgraded valve covers had been installed previously), but the current pulley is extremely close to the existing shroud...we're talking a hair. Might I already have the bigger fan/shroud?

Miguel Antonett · 04-23-2007, 03:52 PM

A carrera cooler will be an improvement, a Mocal will be better yet, they really don't need that much air flow to do their job, but OBVIOUSLY the more air going thru the better they perform.

Jack Olsen · 04-23-2007, 04:11 PM

You've already got plumbing to the wheelwell, right? My concern with putting it behind a piece of fiberglass on a street-driven car is that you're increasing the chance of it hitting a curb or other obstacle -- for what would probably be a negligible change in cooling capacity (with your sucker fan idea). Why not keep it simple and add a Carrera cooler and a fan?

Danny_Ocean · 04-23-2007, 04:16 PM

Yes, plumbing is present where attached to the original trombone. When you say "Carrera cooler", I'm assuming you're referring to the fender mounted replacement for the trombone? My body kit fenders do not follow the same contours as the original fenders, therefore I am concerned the fender-mounted cooler (Carrera?) won't fit.

IROC · IROC's Garage

Quote:

Originally posted by Danny_Ocean
Do you have a source for the Mocal kit? I did a cursory search here, but didn't find it.

Try here:

http://www.racerpartswholesale.com/cooler.htm

and scroll down to 911/930 coolers...

Danny_Ocean · 04-24-2007, 05:59 PM

Quote:

Originally posted by Grady Clay
Your ‘79SC has a smaller engine cooling fan than most other 911s. It is 226 mm diameter where most others are 245 mm. You already have the large (134 mm crank pulley. Find a late 11-blade fan and housing to get the larger 1.82:1 fan and ratio.

Not only will it improve engine cooling where most important (heads & cylinders) but will even improve the A/C performance.

Woo-hoo! I measured my fan today and it is right at 245mm & 3.25" for the pulley. I guess the previous owner did this mod.

Now, onward with the cooler install.

Thanks all,

D. Ocean