Question about Upgrading the 1984 Fender Oil Cooler

gtc · gtc's Garage

Does the radiator style oil cooler used in the '85+ 911s just swap in for the 28 row brass cooler on the '84, or do I need to replace some of the oil lines and brackets?

Jeff Alton · 02-21-2011, 04:22 PM

why replace the cooler? The 28 tube cooler you have is superior in a street environment than the later cooler....

Cheers

gtc · gtc's Garage

My oil temps are fine during most normal driving, but they get too high in bad traffic and when I'm driving spiritedly on tighter (slower) roads.
I have thought about installing a cooler scoop to direct air to the cooler from either the fog or marker light opening, but that wouldn't help in traffic.

Bill Verburg · Bill Verburg's Garage

The plumbing swaps over, don't know about mounts but they sure look the same

Wil Ferch · 02-22-2011, 01:52 PM

I've added a 7.5" SPAL fan on my previous 85 that had the radiator style....forcing a movement of air over the tube style ( '84) may also be good but maybe not as effective. If it only seems sub-par at idle or slow traffic.... it would seem to respond well to a fan too. Fairly cheap compared to your other possible options.

James Brown · James Brown's Garage

I think a fan is all you need. with a switch so you can control the temp in slow traffic. That is a easy fix.

gtc · gtc's Garage

The fan might work in traffic, but I'm not convinced it would help at speed.

I haven't seen any figures for the brass cooler's heat rejection, but I have no doubt that the radiators beat them easily as soon as you get some appreciable airflow.

Buying a fan for $75 and a cooler scoop for $90 brings me pretty darn close to the $215 cost of the repro Carrera cooler (Tasker brand, via Pelican).

rusnak · 02-22-2011, 04:28 PM

The finned cooler w/o a fan is pretty terrible. The fan should be wide enough to push a good amount of air, so you feel it coming out hot on the other side. It's a tight fit in there. Most likely you will need to buy or make some mounting brackets, or move the horn.

jwakil · jwakil's Garage

I did the upgrade you are considering. As with everything, the first time you do something it is a lot more work than you figured. Getting those short oil lines on and off the copper pipes and the cooler itself can turn into quite a b-tch. Makes it easier if you have two people, one to align the pipes and the other to screw the nuts. Otherwise you can get them stripped. You will need to rig up some kind of a bracket for the top of the cooler. That's the only thing that's really different as far as mounting. The fan is definitely needed when stuck in traffic. Without the fan, you are not much better than the brass cooler. I got a cheap generic one that works pretty well. Luckily it had two mounting points that matched up with the edge of the cooler.

If you have vacuum retard on your distributor, I would suggest disabling that first to see if your idle temps go down. I think that made a bigger improvement for me than the cooler upgrade. The air scoop alone is not going to do much of anything.

Quicksilver · 02-23-2011, 12:12 AM

Quote:

Originally Posted by jwakil

. . .

If you have vacuum retard on your distributor, I would suggest disabling that first to see if your idle temps go down. I think that made a bigger improvement for me than the cooler upgrade. The air scoop alone is not going to do much of anything.

Unless it is a turbo all of the 84 and later cars are Motronic. The computer does all the timing so there are no hoses to the distributor.

DRACO A5OG · DRACO A5OG's Garage

I added an Elephant Racing fan with adjustable thermal switch to kick in right at the 190 degree mark on the Oil Temp Gauge.

It helped in stop and go traffic ( and waiting in in drive thru with A/C on during summer ). I know your set up is not the same but what I did from suggestion from a well known member here is to add plastic liner from a spare wheel well liner at the bottom so the forced air will not just blow out the bottom. Just cut to shape and drill holes and use the mounting bolts at the bottom to hold in place. No other mods.

You could do what my buddy did and remove the side marker and fab a mesh (sprayed painted black ) in place and it will at like a less direct scoop at speed and if you ad a fan allow more air to flow in.

At speed no effect, the rear oil cooler works perfectly well.

Jim

Wil Ferch · 02-23-2011, 07:09 AM

Since the original poster specifically said there was a problem in traffic or not-moving conditions, it implies all is well...or at least OK...while moving. That suggests that air flow has a positive effect. Therefore a fan might not be a bad idea to try at low cost.

If you do, suggest using a manual , lit switch to activate the fan...you have more control that way. There is a cut-out on your dash already there normally used for a rear wiper switch....just "feel" for it ! Best also to wire-in a relay. Here is what I did--->

Wil Ferch · 02-23-2011, 07:23 AM

I also did this.....a bit more involved than it looks.

- inverted and mounted front signal housing to the side. Inserted a wire harness that I made, inside that module.... per Daniel Stern lighting instructions....to make for a "blinking" side marker light. Uses the external male spades on that housing to feed wires to the "side-marker"....but side marker light is now mounted to the front.
- used Porsche Euro side marker and placed in front, instead of normal side marker, to make a forward-visible blinker... and is a smaller size that allows more direct air flow to the oil cooler. This front light gets power fed from the external spades on the other light pod now moved to the side.
- cut up old rear deck grill... for the grill here...some fab work required to mount a small sheet metal holder.
- removed trumpet horns that block air flow to the cooler, and used "puck" horns mounted lower.

Wil Ferch · 02-23-2011, 07:30 AM

Actually....gives a nice impression of both a long hood and short hood car, with the grill used for the long hoods--->

Flat Six · Flat Six's Garage

Quote:

Originally Posted by Wil Ferch

Actually....gives a nice impression of both a long hood and short hood car, with the grill used for the long hoods--->

Dang, Wil -- nicely done. Looks over-engineered (a big compliment in my book!).

Are those two plugged holes in the hood just above the front plate? What are/were they for?

Dale

Wil Ferch · 02-23-2011, 08:17 AM

Of course over-engineered...because it was a hobby-project...not a paying job ! ( LOL ! ). I love noodling on my car.

Ahh.....I tell people the two little grommets on the hood are for the removable Cibie Oscars, and they all walk away nodding. Truth?.....one covers a nasty scratch and the other is placed in the mirror-image location to make it seem like grommets. Only a piece of vinyl that avoids a respray to an otherwise near perfect paint job elsewhere.

And before anyone asks...yes, those are flamethrower driver lights ( Cibie 35's ) down below to get rid of those awful useless fog lights.....

,

.......

Flat Six · Flat Six's Garage

Quote:

Originally Posted by Wil Ferch

And before anyone asks...yes, those are flamethrower driver lights ( Cibie 35's ) down below to get rid of those awful useless fog lights.....

,

.......

Looks like they could melt snow & ice on the road ahead

wildcat077 · wildcat077's Garage

Hey Will,

Congrats on post 10,000 and that nice looking air scoop

Cheers !
Phil

gtc · gtc's Garage

Wil,
Thanks for sharing. Your switch is set up exactly how I had planned.

I guess I will just have to buy a cooler to see what bracketry will be needed. It sounds like my oil lines will work, so that is a plus.

Wil Ferch · 09:01 AM

Glad to help...man, gotta stop posting so much....or maybe start with a new Pelican name

Double edged sword.....poor business means allowing more time to post here...also means business was bad enough to help with the decision to sell that car. Miss it.