Diff Cooler Necessary for HPDE?

[starnsey]

I've got a Cobra IRS in my Mach 1 and I've seen a lot of the racers here seem to use a differential cooler on the IRS. I'm not trying to make my car a race car but I would plan on doing some open track day events. I know the sessions are typically between 10 and 20 minutes. Would it truly be necessary for me to have a differential cooler (I'm talking about maybe once or twice a year of HPDEs)? Majority of time would be on the road or auto-x.

Obviously, I don't want to have to worry about destroying the internals of my rear end, but I really don't want the ugly heat extractor showing out the back end of my car. So would I be able to get away with it okay or would it be best to stay off the road course?

 

[99COBRA2881]

Not needed. The higher temps will degrade the oil faster so plan on changing the diff oil yearly. I drilled a small hole in the bottom of the IRS pumpkin and tapped it for a npt hex plug this allows easier draining of the diff.

 

[starnsey]

Not needed. The higher temps will degrade the oil faster so plan on changing the diff oil yearly. I drilled a small hole in the bottom of the IRS pumpkin and tapped it for a npt hex plug this allows easier draining of the diff.

Alright, perfect. That's no problem. The IRS is completely upgraded bushing wise and has the upgraded FRPP cover with drain plug (thank goodness)

 

[Jimmysidecarr]

Not needed. The higher temps will degrade the oil faster so plan on changing the diff oil yearly. I drilled a small hole in the bottom of the IRS pumpkin and tapped it for a npt hex plug this allows easier draining of the diff.

Ditto, not needed . Except yearly lube change out for only two track events a year is actually significant over kill, if you are using Royal Purple Max Gear 75W-140 (part #01301, quart bottle) and possibly some other high end synthetic gear lubes..

:beer:

 

[starnsey]

Ditto, not needed . Except yearly lube change out for only two track events a year is actually significant over kill, if you are using Royal Purple Max Gear 75W-140 (part #01301, quart bottle) and possibly some other high end synthetic gear lubes..

:beer:

That is in fact what I use :beer:

 

[wheelhopper]

Third the motion that the diff. cooler not needed. I drive the crap out of my '90 GT with an IRS and have been for 3 years. No problem. I do about 25 track days a year and simply change the diff. fluid at the beginning of every year.

 

[ac427cobra]

I've been doing track events since 1996 and I have never done a 10 minute session. However, I have done sessions of 20, 25, 30, 40 and unlimited. Ok, technically not unlimited, but 8:00am-Noon and 1:00-5:00.

There are many factors that come into play to determine whether or not you need a diff cooler on your car. Here are a list of some things that come into play:

1: Your RWHP. The higher the HP the greater the chance there 'may' be a need for one.
2: Your experience level. Typically newbies are not going to be pushing the limits of a vehicle.
3: Gear ratio. Stock 3:55 gears run cooler than 4:10's.
4: OEM clutched diffs run hotter than say a Torsen T2-R.
5: The track you are going to. Faster tracks generate more diff heat.

You 'may' very well be able to get away without a diff cooler and you should have an IR thermometer in your tool box to check the temperature of your diff housing immediately when you return back to the paddock from a session. If you are experiencing temps over 250 degrees, (it will be hotter on the inside) you need a diff cooler.

You should have a hose connected to your diff breather fitting and run it straight up into your trunk to a catch can, that way if your diff does puke it won't be puking all over your hot car and hot exhaust.

We have been getting more and more requests for diff coolers and we are finally putting one together. We should have one on our site in the next week or so.

I hope that helps.

:thumbsup::coolman::beer:

 

[N/Angel]

We have been getting more and more requests for diff coolers and we are finally putting one together. We should have one on our site in the next week or so.

I hope that helps.

:thumbsup::coolman::beer:

that's good news, I was going to put together my own kit but just didn't have the time. Now I'll wait for yours to be available to see if it fits our needs.
your bushing kit for the IRS was the best purchase ever made for the car :beer:

 

[03 DSG Snake]

Love seeing FTBR keep pushing out the new parts. :rockon:

 

[Bingo13]

We have been getting more and more requests for diff coolers and we are finally putting one together. We should have one on our site in the next week or so.

I hope that helps.

:thumbsup::coolman::beer:

Damn Bruce, are you just trying to get me in divorce court?

 

[03 DSG Snake]

We have been getting more and more requests for diff coolers and we are finally putting one together. We should have one on our site in the next week or so.

I hope that helps.

:thumbsup::coolman::beer:

How about a bolt on Oil Cooler setup for the 4vs after that? :dancenana:

 

[TDS-03]

This is completely the wrong timing. Bruce is only supposed to add a new product after I have spent way more on the same thing somewhere else.

 

[Steveespo]

If you have ever checked your diff lube temp after a 30 minute session in 90 degree weather you would be amazed at how hot the 8.8 will run. I have 3.55 gears and a Torsen T2 and after blowing the left axle seal I decided to check temps. Added the 2013 GT 500 diff cover and drilled the sensor port for an Auto Meter sensor. Got up to 285 degrees after the second session at Lime Rock Park. The next week I put together a system using a Cup car Long power steering cooler, a Tilton pump, some Aeroquip lines and fitting and a console mounted toggle switch. At 235 the warning light on the gauge comes on and I throw the switch. Haven't had temps above 250 since. 275-280 should be considered the absolute upper temp for even the good GL-4 synthetics that Motorcraft, Mobil, and Redline have. Above that parts will start to fail.
Steve

 

[99COBRA2881]

Where's your exhaust routed?

 

[wheelhopper]

Out of curiousity, what weight with driver is your cars that are using the diff. coolers? I am right around 3200lbs. If it wouldn't push me out of my class I could easily get to 3000lbs. Just wondering if you guys are much heavier than I am and that is why I don't have any issues with my IRS diff.

 

[99COBRA2881]

Post race weight is about 3250 w/ a 240# driver. 3.73s and an auburn diff. Exhaust goes out through the body in front of the rear tires.

 

[Steveespo]

Exhaust is routed out back stock location. All up weight 3848 and 432 RWHP. Torsen diff, 3.55 gears. I run the spec Motorcraft 80-140 Synthetic.

 

[wheelhopper]

Not to many responses about the weight, but as I am suspecting, it looks like those that are seeing high temps and having issues with the IRS are in full weight cars. Cutting 500+lbs off the car makes a big difference on how the IRS performs. An added benefit is the car will be faster, the brakes will work better, and the suspension components should last a little longer.

 

[99COBRA2881]

Wrapping the exhaust under the diff will also help lower temps. in the IRS.

 

[wmfateam]

Wrapping the exhaust under the diff will also help lower temps. in the IRS.

Do you have any under car pictures or in car pixies on how you routed your exhaust?