Nissan 370Z Forum - View Single Post - STILLEN 370Z Supercharger System

Phimosis · 12-12-2010, 08:52 PM

Just a short update: I melted my Stillen HFC's during a track session. The cats had about 8k miles on them, 3k with supercharger. about 10 minutes into second session, after a redline shift, back to 5k, then off the throttle and "pop!" like a backfire, then the engine note changed and power was way down. I shut it off, called it a day, talked to the guys at Stillen (it threw a cataylst insufficiency code) then took it to a local mechanic. He took it apart. Both cats were melted. One core broke loose and was serving as a cork in the HFC's outlet.

I put the stock cats back on it and it runs fine. Maybe a little down on power, but not a lot. Has a less macho engine note too. :-(

Why do I post this? Because leaning out the a/f ratio is the most likley reason to get a cat hot enough to melt. Granted, I had prolonged, high rpm, full throttle use... but add the lean condition and it's gonna get real hot. The concerning part to this is that on the dyno, my car is pretty rich under boost all the way to redline. Is there something in real world driving - like fuel washout under high lateral g load - thats causing a lean condition? Just throwing it out there.....

12-12-2010, 08:52 PM	#2457 (permalink)
Phimosis Enthusiast Member Join Date: May 2009 Location: Oildale, CA Posts: 412 Drives: 2013 911 4S Rep Power: 416	Cataylitic fondue Just a short update: I melted my Stillen HFC's during a track session. The cats had about 8k miles on them, 3k with supercharger. about 10 minutes into second session, after a redline shift, back to 5k, then off the throttle and "pop!" like a backfire, then the engine note changed and power was way down. I shut it off, called it a day, talked to the guys at Stillen (it threw a cataylst insufficiency code) then took it to a local mechanic. He took it apart. Both cats were melted. One core broke loose and was serving as a cork in the HFC's outlet. I put the stock cats back on it and it runs fine. Maybe a little down on power, but not a lot. Has a less macho engine note too. :-( Why do I post this? Because leaning out the a/f ratio is the most likley reason to get a cat hot enough to melt. Granted, I had prolonged, high rpm, full throttle use... but add the lean condition and it's gonna get real hot. The concerning part to this is that on the dyno, my car is pretty rich under boost all the way to redline. Is there something in real world driving - like fuel washout under high lateral g load - thats causing a lean condition? Just throwing it out there.....