View single post by Ron Earp
 Posted: 09-05-2005 01:51 pm
PM Quote Reply Full Topic
Ron Earp

Joined: 03-12-2005
Location: Cary, North Carolina USA
Posts: 339
Duct, duct, duct.  Did I say duct?

Improved Touring has LOTS of cars that have solid rotors and less than optimal brakes for severe race duty.  But, they can be made to work and work well.

For example, Datsun Z cars run in IT with solid discs, rear drums, and weigh in about 400lbs heavier than a JH with more motor to boot. With no care taken to lines, fluid, and ducting the brakes will be done in within two laps, no kidding.

But, with care to lines, using high boiling point fluid (550-600F) that is always fresh, race pads, and the big one - two ducts to each wheel, the brakes will last a 45 minute race with no fade which is a heck of a lot more stress than you can come up with doing any street or spirited driving on back roads.  You need one duct to the caliper itself and the other duct goes to the rotor hat.  A rotor hat is simply a metal tube with a slot cut in it where the rotor spins through and the tube is bolted somewhere convienent so it won't move around. A air tube is clamped to the hat and thus air is blown on both sides of the disc.

Ducts are easy to make, really work, and are cheaper than fitting aftermarket brakes, calipers, etc.  Right now I'm laid off my JH prep because I have a spec Miata to finish up, but once I'm back on it I'll finish the duct work and shoot some pictures in case anyone wants to duplicate them. 

Just duct it.


Last edited on 09-05-2005 01:53 pm by Ron Earp