PorKen

Much easier this time than with (my 3-spd).



I used -6 Aeroquip AN socketless (push-on) fittings and hose again.

Flex-a-lite 4109
9000GVW Frame Rail Cooler

-6 fittings
(2) FBM2240 14mm x 1.5 adapter
(4) FBM1532 90°
(2) FBM2052 union
(4) FBM1512 straight

10' socketless hose
(1) 36"
(1) 30"
(2) 27"



Total cost ~$200 from local vendors.

PorKen

It's mounted using the big bumperette nuts, in place of the big washers.

A 120° fitting would probably be better for the outlet on the left side of the trans than the 90° I used. There's room, but it's tight.

I used unions to split the hoses over the axle. This made it much easier to string the hoses.

By summer I want to make a thermo-switched fan for it. I'm thinking a 3" bilge fan, connected via hose to a windshield defroster shaped duct blowing down through the cooler.

ZEUS+

Is this to be used with the existing cooling system or as the only cooling for the trans ? With fluid temps of 300 degree plus, it will still need liquid to liquid for effective cooling.

heinrich

I like it.

IcemanG17

Ken
So you disconnected the factory dual coolers? Unless you seriously track the car is it needed?

69gaugeman

Or for towing of course

PorKen

One thing I'm deathly afraid of is coolant in the ATF, or engine oil for that matter. I will change the engine oil cooler at some point.

The front coolers are disconnected, but not yet removed. There is less overall cooling surface, but there is less oil volume to cool, and it is easier to pump with only 10' of hose, and no banjo fittings!

I have never seen external pan temps higher than 220°F with my 3-spd, and that was going over the mountains from OR to CA. Most of the time the pan temps are 140-160. The four speed converter is 'tighter' than the 3 (slips less = less heat), but then again there's more power to turn it.

When I get around to tracking the car, I will add a fan/cooler combo in the fender. Right now, I will probably swap this 20" cooler (which I had laying around) for a Derale 13225 24" cooler.

PorKen

The effect is good as it was with my 3-spd. It kinda feels like you have more pedal, as the rpms don't jump as high when you roll on the throttle, especially on the freeway. There is less amplification as the converter is harder to spin, and I can hear the engine straining more. (A little cam advance will fix that, I have 0°, now. ) Engine braking is improved, and running in 1st/2nd is a lot more fun.

I'm impressed with this little cooler. Driving around in 60°F weather, my pan temps vary from 125-145, measured at the front of the pan. The front of the pan is 20° or more hotter than the rear, I assume that the converter dumps into the front.

John Veninger

I'm with Zeus+
Once it gets hotter outside there won't be enough airflow to kkep the fluid cool and you'll see higher temperatures.
If you really want to get rid of the internal water cooled cooler, then you need to mount a fairly large air to air cooler in front of the radiator.

PorKen

If water/oil cooling is the end all, why is the engine oil cooler 90- air only?

Air doesn't evaporate as it travels from front to back. When the car is in motion, cool air is sucked in front of the rear tires, and entrained in the air flow under the car.

I have had a similar system on my '81 for almost four years. 160°F external pan temps in 90°F weather, without a fan. The '86 has 100 more RWHP, but, the torque converter is larger, and the overall gear ratio is lower.

For low speed cooling when the weather heats up, I'm planning on a smallish stacked cooler (<10") and fan. This cooler would not need to be in direct air flow.

John Veninger

I was told the main reason they moved the oil cooler out was to allow the existing radiator to handle the increased cooling needs of the GT then GTS.

Personally I hate the 90+ oil cooler. They mounted it under the radiator with the thought of selling you a new one every time you rub on a curb or steep driveway

ZEUS+

I do think it is a great idea. I have seen quite a few trannys get lunched from ruptured coolers and some survive. If the adhesive that bonds the friction material was not affected by ethyl glycol, it would not be a catastophic failure. Just a big mess. Coolant sheds heat better than oil. It would be nice to eliminate that potential catastrophe.

doktor-t

I ran to pretty small oilcoolers with 12x12cm computerfans in my Camaro. It worked fine and there were even a higher stall converter in that tranny. I didn´t use the original cooling throu the radiator for safety reasons such as if the engine run hot, the tranny won´t

/Tobias

doktor-t

I actually might try this in my 928 aswell since it got it´s original radiator and my oilhoses started to sweat a bit. Would be nice also to get rid of these long hoses and piping running from back to front.

TAREK

I'm all for separating the coolers too, and have bought the parts for the project, except it's not my highest priority...though I live in Florida

My question is how did you measure the temps? do you have 2 gauges permanently installed? Are they the generic temp gauges you can get from the chain parts stores?

Also, do you see a drawback to using a larger cooler for the extra hot zones? My 928 is a daily driver and sometimes I sit in 100 degree temperatures in traffic for hours. I could swear you can fry an egg on that thing an hour after it stopped

thanks
Tarek