View Single Post
Old 11-30-2012, 06:47 PM   #20
Beastly Adventurer
Joined: Dec 2006
Location: North Cowichan
Oddometer: 3,070
The only time I ever had exposure to Iridium spark plugs was on De Havilland Beavers or high performance Twins back when I started my aviation wrenching career. Performance enhancement? I didn't believe this was the reason that we used them. It was merely to improve serviceability on these engines between scheduled maintenance checks. Standard plugs would erode severely between the 100 hour intervals that existed between plug removal and testing. Many times the rear plugs on the Pratt & Whitney 985's would be seized and removal might mean the damaging of the cylinder head/spark plug holes - best to leave them in and look with a flashlight through the front plug hole and see how they were doing.... Throw some Iridiums in the back plug hole and things held together longer. On the high performance horizontally opposed engine end of things, the bottom plugs would always get covered with all the junk - just the same way our dual plugged Beemers do in their much easier working environment. So all you folks who think that you're creating a race machine by throwing in these plugs, by all means do so. I'll carry on running my NGK's which never seem to erode at all.....
jackd is online now   Reply With Quote