Front oil cooler installation & pics

[MuffinMan]

Unfortunately, my 2nd generation RX7 oil cooler was not getting the job done on the track for my 3.6. It was adequate for the old 2.7, and up to ~8/10ths with the 3.6 on the track, but once I started to really whomp on it with a clear track, the temps got too high. The old cooler was installed with ~1.5" between the cooler and the front tub, so there was room for airflow there, but clearly not optimal.

I decided to cut the tub and install a sheet metal piece for better airflow, along with the installation of a big mother cooler. I bought the biggest cooler I could find, which turned out to be the B&B FPOR-9400 Front Spoiler Mount Oil Cooler, with a core size of 6" x 3" x 24". I figured better airflow and the big honkin' cooler would solve my issues. Here is the project:

This is my 2nd generation RX7 cooler:

[MuffinMan]

Since my metal fabrications skills are limited, at best, I decided to use the Elephant Racing RS/RSR replica duct.






Here is the B&B cooler next to the RX7 cooler. I think it's safe to say that it's bigger...

(the perspective is skewed, but it is notably larger)





This is RX7 cooler with the front valence removed.






RX7 cooler removed

[MuffinMan]

I initially began cutting the tub with an air-driven cut-off tool. The progress was very slow, as the tool didn’t have enough power to mow through the tub. My dad came over the next day and brought an electric grinder with a cut-off wheel, to save the day. This thing is much more powerful than the air tool, and sliced through the tub like butter. The metal shavings flying everywhere were the only thing slowing me down! It was very challenging to get the size of the hole cut correctly, but it's close enough for government work. If I did it again, I would probably be able to get the hole a little tighter to my sheet metal piece, but I'm happy with it.

Initially, I was planning on having the piece welded to the tub. After a lot of thought, we decided to rivet it in place with JB weld squeezed between the duct and the tub. I am happy with this approach, and the duct is not going anywhere...like ever. This is clearly the hardest part of the job, imo, but we'll find out soon enough!



The destruction begins! (My friend, Shawn, swung over to help cut my precious car into pieces)









Here’s my dad…with more power!

[MuffinMan]

The damage is done!






The duct is installed




Here are some comparison pics

[MuffinMan]

I got the mounting scheme idea from Steve Weiner. The idea is the hinges give the cooler a little big of give if there’s any sort of impact, while the big, fatty oil lines hold the cooler in-place and stop it from swinging.







The last step was to purchase another 45 degree hose end and fasten the oil lines to the car with more hose clamps. I tested it at Watkins Glen a few weeks ago, and although it was cold (in the 60’s), I think it’s safe to say that between the better flow and bigger cooler, the project was a success.

[Chuck Moreland]

Looks good. The size difference between those coolers is dramatic.

If you haven't already, I'd put some seam sealer on the new RS Duct to prevent water intrusion, both sides. I'd also seal the front of the cooler to your bumper opening to prevent any air from getting around the cooler.

I'm sure this will get your temps down.

[prooutlaw]

Do you want to sell the old Cooler ? How much ?

[MuffinMan]

Chuck, thanks for the tips. Although the duct is quite tight now, I'll follow-up with a sealant to ensure a perfect enclosure. Your duct made for a professional-looking installation, and made the whole thing a bit easier.

prooutlaw, you missed the cooler by a couple of days. It just sold in the classifieds.

[Joeaksa]

Very nice work and something to think about in the future for my car.

Joe A

[Wil Ferch]

IMHO.... although this is an excellent write up...

my opinion is that you didn't optimize your original cooler set up...in allowing air to flow around the edges of your original cooler. My view is that a concerted effort to effectively seal the edges around the cooler ( and forcing all the air flow THROUGH the cooler)...may have done the trick without resorting to cutting up your tub....

Still ...nice job !

Wil

[TonyG]

Wil Ferch

You hit the nail on the head.

Nice job Muffinman, but make sure to seal your air intake to your oil cooler. Air will take the path of least resistance (and going around the oil cooler is much easier than going through it).

TonyG

[Yellowbird RS]

great upgrade
nice work

[randywebb]

I like the pic of you cutting with a spray of sparks headed to the GAS TANK!

[Bill Verburg]

This thread should be called the "Ultimat Front oil cooler" installation & pics

[DW SD]

Rob,
Sweet setup! To where did you mount the hinges? What is that rubber pad in front of the hinge? Does it get bent at a 90 with the hinge or does the hinge remain straight, installed?

Thanks,

Doug

[88 Club Sport]

Great set-up as long as you are not running in a stock class. Most stock classes do not allow cutting of the tub.

I wish I could have done it your way but my Setrab seems to keep me below 230 while at at the track.

[Bill Verburg]

Most stock classes do not allow cutting of the tub.

That's interesting, I hadn'yt hheard that before. How sure are you for PCA?

[Shuie]

Nice work!

[88 Club Sport]

Pretty sure Bill. With his 3.6, big reds etc., it's not really an issue for Rob though

[MuffinMan]

Originally posted by DW SD
Rob,
Sweet setup! To where did you mount the hinges? What is that rubber pad in front of the hinge? Does it get bent at a 90 with the hinge or does the hinge remain straight, installed?

Thanks,

Doug

I bolted the hinges into the vertical portion of the tub, just above the duct. The rubber piece you see is simply a rectangular piece of rubber I cut from a random sacrificial item from The Home Depot. It remains straight when installed. I was worried that it would sway back & forth with the hinge, but between the subtle stiffness of the rubber isolation pieces and the hoses fastened to the body, very close to the connection point, it is a very rigid setup. Theoretically, there is a bit of give in the case of an incident, hopefully minimizing internal damage to the cooler. I hope to never find out if it works as planned!

Pretty sure Bill. With his 3.6, big reds etc., it's not really an issue for Rob though

Yes, I think it's safe to say I no longer qualify for stock classes