Rear fender oil cooler mount details, How I did it Options

[IronHillRestorations]

After I made a post about my alternate location for an auxiliary oil cooler, I thought more details would be helpful.
First let me say that this was a piece of cake for the current project, as the right rear quarter panel was removed for rust repair and chassis stiffening. Due to the difficulty in properly locating the forward mounting holes, I don’t know how feasible this is for a car with the engine installed. When I put a (slightly smaller) cooler in this same area 25 years ago, I made no notes or kept any of the measurements, I just made it work, but at that time it was done with the engine out of the car.
After trial and error fitting of a cardboard mockup, I picked a Mocal 34 row, 235 matrix cooler, which measures 260mm by 280mm, or roughly 10 5/16” x 11 1/8” which doesn’t include the -12AN fittings. This is what I think to be the largest cooler you could get in that area ahead of the right rear wheel. This cooler has a capacity of .75 quarts, which is .20 of a quart more than the kit BAT offers to upgrade a 911 front oil cooler. This is a case where bigger is definitely better.
Since airflow in the rear quarter panels isn’t as good as the front fender , I added a 7” Spal puller fan that will be mounted directly to the oil cooler with a plastic mounting tie kit, which are very sturdy round zip tie fasteners that make it easy. The fan will be wired with a relay to a switch on the dash or an automatic inline switch (to be determined later). On my old install I tried to make the fan automatically switched, but it ran too much and the fan died. A testament to this set up is that I never knew the fan died, and oil temps never got over 220* even in the hot Tennessee summers. Since this is going to be a widebody hot-rod with flared rockers, I’m toying with the idea of incorporating a scoop in the rocker flare, but that too is undetermined.
Here’s a hardware list, that doesn’t include any oil lines, thermostat, or relay wiring for the fan.
1 Mocal A34A12 34 row -12AN 235 oil cooler
2 Mocal/Setrab ABKT-235 oil cooler bracket for 235mm core
1 BAT ABKT1 cooler/fan mounting tie kit
1 M8 x 1.25 x 60mm fully threaded cap screw (13mm hex)
2 M8 x 1.25 x 50mm fully threaded cap screw (13mm hex)
12 M8 washers
8 M8 x 1.25 nylon insert nuts
1 M8 x 1.25 weld nut

Even with the fender off it took more than one attempt to get it in the optimum location, which is as far forward as possible without interfering with the outer suspension console. Using the suspension console as the baseline level plane, the cooler is tilted down at the back about 5* give or take a degree.


Just for reference

Here's what the cooler looks like mounted. It's pretty big.


I wanted to make sure the cooler could be installed and removed with the fender on, I made sure there was no interference. I had the fender on and off several times during the test fitting process.
With the fender off it was easy to use the bracket as a reference where to mark and drill the 5/16” front mounting holes, which are 70mm apart.

[IronHillRestorations]

On a street car, I'd add another cooler under the rear trunk before I'd put one up front, for reasons already stated.

For a track car, I wouldn't put it anywhere else than up front.

All the information I've been able to find says 210* is what you want, which is when the water in your oil will vaporize. Over 240 for extended periods isn't advisable.

A fresh tight engine will always run cooler than a tired one needing a rebuild; the old engine will have more blow-by in the case which will raise oil temps. So the fresh 230hp 2.7 going in this car will run cooler out of the box, than your old 2.0T engine that burns a quart every 500 miles.

[DRPHIL914]

On a street car, I'd add another cooler under the rear trunk before I'd put one up front, for reasons already stated.

For a track car, I wouldn't put it anywhere else than up front.

All the experts that I've spoke with have told me 210* is what you want, that's when the water in your oil will vaporize. Over 240 for extended periods isn't advisable.

Mine is up under the rear trunk with a good angle to it and seems to allow a sufficient amount of air to move thru it. I didn't have that fan wired up for the drive in Helen, and up the hills I topped out right at 230-235 but never went over that, and only hit that as a max during long steep hill climbing. Last year on the same hills and the year before in Banner Elk, NC, with the fan kicking on at about 220, it never went over 220 , verified with dip stick thermometer. I used to also see some pretty high oil temps here in the summer heat in SC just on the highway and this was why we put the aux oil cooler in in the first place, but with the aux it stays a good 20 degrees cooler. so I can see your point about not requiring a front cooler unless you are racing. I don't plan on tracking the car, and its cool to see that your set up in the rear is good enough even for a nice /6 motor! How far out are you from actually having that car on the road? have you posted a build thread with details of the rest of the restoration?