Rear differential cooler
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Speaking of HD caps. Has anyone seen any strength testing between the straps and the HD caps? I've replaced a bunch of HD caps being run on the street with mild motors because they stretch out leaving the u-joint loose.I've never seen this with the lighter duty caps even with some cars running big blocks and large tires.
Team Owner
Joined: Jul 2004
Posts: 40,380
Likes: 788
From: Redondo Beach, California
The differential gets hot because of the HP loss. An acquaintance of mine has spent really big bucks on his C4 and one thing he recommends is having the differential REM treated. Don't know what the acronym stands for, but the idea is that the ring and pinion are given a quick dip in a corrosive bath and then the ring and pinion are placed in a vibrating tub of small abrasive ceramic particles. This process is repeated two or three times and the net result is that the ring and pinion are left with a mirror like surface finish. The story is that friction between the ring and pinion is greatly reduced, heating is reduced, and you don't need a diff cooler. He's had the gears in his transmission similarly treated. The abrasive treatment doesn't go deep enough to disturb any surface heat treatment. The REM process produces a noticeable horsepower increase at the rear wheels according to their brochure. I'll try to get back with the name of the vendor.
