IRS Differential Cooler

[PaleRider]

subbing

 

[Maynor]

John,

Fumes may be an issue, I have yet to drive the car but that thought did cross my mind more than once when I did this. I will be running on VIR South this weekend, so I will let you know. If it does get to be too much, I am thinking I will put a vent tube down to the rear baffle in the passenger corner of the trunk.

I should probably go ahead and fabricate something in case the smell is too much on Saturday. The bad thing about VIR South is there really isn't a hard left turn to test out my g-load theory. Other than T4 on South (which is really an uphill braking zone and then a hard off-canter left after you crest the hill), everything else is a right turn or a low-g left turn.

-Kevin

I just spent the past two days at VIR. Full course. Even with my vented to the outside catch can, the fumes were pretty strong in the car. I'm going to need to find a better way of way to seal off/vent the catch can and/or seal off the rear seat area.

A small puller fan would be ideal but it might be as simple as using Teflon tape on the screw in hose fittings. Anyone else have this problem?

John

 

[PaleRider]

Not trying to get off topic, but looking at ways for a cooler IRS. Anyone familiar with the MikroMax High Performance Ring & Pinion gears? Can their claim be real?

 

[pkwest]

PK, thanks for the pics. One concern... how do you manage airflow through radiator?

99 Cobra, yes, it will help.. Its just a pain to mount them if you have subframes and want to maintain some ground clearance.

I just ran at willow springs in 101 degree temps and the differential temp was 207 degrees. No fan needed.

 

[brkntrxn]

BTW, I ran two days on Roebling Road last week and had zero fume issues with the diff vent/catch can being mounted in the trunk.

 

[Sintore]

I run a Detroit Locker in my 8.8 IRS carrier and haven't had any problems in two season...even when running 90 min. races. I did have a lot of overflow with the clutch type diff and didn't like maintaining the clutchpacks...

 

[mmustangsrus]

op:

 

[SilverNotch]

I was wondering how loud these pumps are? Will I hear this over exhaust?

 

[ac427cobra]

I was wondering how loud these pumps are? Will I hear this over exhaust?

You'll hear the pump at idle in the paddock but not on the track.



:thumbsup::coolman::beer:

 

[mmustangsrus]

if this isnt a sticky in this forum it should be :rockon:

 

[VNEMUS]

I completed my IRS Differential Cooler set-up at the beginning of last year and realized I never posted an update to this thread.

Here’s a couple pics of the oil pump and oil cooler mounting rack that I had a local fabricator (Tube Chassis Designz) make for me based on some specs I drew up for what I wanted. The second pic shows the rack with self etching primer and a couple coats of flat black paint:

Here’s some pics of the parts I bought from Racer Parts Wholesale to put together my rear differential oil pump & oil cooler set-up. I originally thought I could get away with 12’ of -8 stainless line, but ended up needing another 6ft’ of -8 stainless line and a few more AN fittings that what I originally thought. Fortunately, I was able to get that stuff last minute at a local roundy-round track shop nearby:

Here’s a couple pics of the disassembly showing the halfshaft, knuckle, tie-rod & brake assembly removed as one piece. With 2 people, it was easier to remove each side as an assembly, rather than piece by piece. The other pic shows what the IRS looks like when the driveshaft is disconnected, cat-back exhaust is removed and the pumpkin and halfshaft/knuckle/tie-rod and brake assemblies are removed:

Here are pics of the differential cover being drilled for the 2 aluminum bungs that will be drilled and tapped for the AN fittings. I used a second cover to modify so I wouldn’t have much down time when the pumpkin was out. The second pic shows the diff cover modified with 2 aluminum bungs welded in for the draw and return fittings & lines. I paid a local guy to do the aluminum welding:

Here’s a pic of the pumpkin with the modified diff cover in place. I have forward and rear Maximum Motorsports solid aluminum differential mounts, rather than factory or urethane bushings:

 

[VNEMUS]

When assembling AN fittings and stainless braided lines, the process goes smooth using the right tools. Koul Tools & AN wrenches, along with a bench vise, 30W assembly oil and steel cut-off wheel made the process easy. The second pic shows a $40 AN fitting that was ruined during “practice” assembly, Lol. One the fittings are installed on the lines, there is no removing them without destroying it:

The first pic shows the mock fitting the oil pump and cooler. The second pic shows the rack, oil pump, oil cooler and some AN fittings and stainless steel braided lines mocked up and ready to install. The fittings on the right side of the first picture coming into the cooler are for the temperature sending unit:

Here’s some pics of the rack, oil pump & oil cooler installed up behind the rear bumper support. The stainless steel lines were run on both sides of the fuel tank on the top shelf area. The lines were zip-tied and I used small sections of black rubber hose as a protection sleeve any place where the line could rub up against something else:
The second picture shows the sending unit installed in-line:

Here some pics of the Diff Temp gauge, manual on/off toggle switch & relay wiring before everything was cleaned up neatly.
The second pic shows the diff temp gauge and manual toggle switch mounted in the steering column pod:

Here’s pic of the differential oil pump & oil cooler install completed:

There were many steps along the way that I don’t have pictures for, but most will get the point. I took my time running the lines, tightening the fittings, filling and cycling the system, checking for leaks and putting everything back together, etc. My diff temps have yet to exceed 205 degrees on track since adding this set-up. I’m so glad I did this.:banana:

 

[SilverNotch]

Looks really nice. Is there any way to keep the cooler and pump out of sight though? So how loud is the pump actually can you only hear it if your in a garage or can you hear it while driving under normal conditions?

 

[ac427cobra]

Looks really nice. Is there any way to keep the cooler and pump out of sight though? So how loud is the pump actually can you only hear it if your in a garage or can you hear it while driving under normal conditions?

If you're driving an IRS under 'normal conditions' you don't need to run the pump.

The IRS needs cooling on a road course when you're on the loud pedal to the floor 90% of the time.

FYI

:thumbsup::coolman::beer:

 

[SilverNotch]

Well when I do your bushing kit I plan on tapping my diff and cap for diff cooler fittings. So when my car is retired from regular street use I can take it to some auto x events and have some fun.

 

[ac427cobra]

Well when I do your bushing kit I plan on tapping my diff and cap for diff cooler fittings. So when my car is retired from regular street use I can take it to some auto x events and have some fun.

Your typical auto-cross run does not generate enough heat to require an IRS diff cooler. However if you're running on a road course at an open track event or racing, your track time can be 20, 30 or 40 minutes long and that will generate enough heat to require a diff cooler with an IRS.

FWIW

:thumbsup::coolman::beer:

 

[brkntrxn]

You'll hear the pump at idle in the paddock but not on the track.



:thumbsup::coolman::beer:

Exactly, Bruce beat me to it. Wire it up on a switch and turn it on when you want it.

 

[VNEMUS]

Looks really nice. Is there any way to keep the cooler and pump out of sight though? So how loud is the pump actually can you only hear it if your in a garage or can you hear it while driving under normal conditions?

My original mounting of the oil pump ended up being a little lower than I wanted (see pic below on left). I actually had an issue driving on the street, pulling out of parking lots or driveways where the inclined transitions of the street and sidewalks or driveway entrances were the lowest pump fitting just barely scraped. The car is low to begin with. The easiest fix was to make a new mounting plate to move the pump up on the rack 1.5 inches (see pic below on right). I have no ground clearance issues now.

Mounting the pump in the rear the way I did was a compromise to what I really wanted to do, which was mount the set up in the spare tire well of the trunk, mainly for safety reasons. My mounts more closely replicated a couple other local Cobra R (Steve C & Dave G) owners’ set ups. I think between the way Bruce and Kevin have their pumps and coolers mounted up on the rear bumper support (with a little fabrication here and there) is the stealthiest way to go. As you can see in the pics, there is a decent amount of space behind the bumper cover, bumper support and fuel tank for mounting options.

Bruce’s set-up:

I wired up a relay with a manual on/off switch, so I can turn it on before going on track and off when I’m done. With the gauge and switch mounted right in front of me on the steering column, its hard to forget to turn it on. The pump makes a vibrating/buzzing noise, but it can barely be heard over the exhaust at idle. I used thick rubber grommets between the pump and where I mounting it to my rack.

 

[SilverNotch]

Bruce do you have any pics of your pump and cooler from the rear of the car? I just want to see if it is hidden behind the bumper.

 

[ac427cobra]

Bruce do you have any pics of your pump and cooler from the rear of the car? I just want to see if it is hidden behind the bumper.

You really can't see my diff cooler until you get eye level to the bottom of the bumper. It's pretty well hidden. But that's because of the 2000 R fuel cell. You're not going to be able to do that with a Terminator. There simply isn't enough room.

This is not the best photo but it's all I could find.

I've got the car on the lift now so let me know if you want me to shoot some pics for you.

:thumbsup::coolman::beer: