Just thought I would check with RandomTechnologies to see what they thought.

And, here is their response:


Maybe I missed something, but I didn't see much on the thread besides
guys saying they were happy with Crawford converters. (Which are
standard muffler shop universal converters with pipes welded to them
to make them direct fits.) The issues we've had with our metal matrix
converters are that they are too flow efficient for the 350Z, given
its stock air/fuel calibration. After chasing the problem for months,
we finally determined that the stock air/fuel mixture at wide open
throttle is extremely lean. When our metal matrix converters are
installed, exhaust system back-pressure is reduced, so the air/fuel
mixture becomes even leaner-- so lean in fact that it causes
intermittent lean misfires. When this occurs, an excess amount of raw
fuel enter the converters, causing them to overheat. Every failed
350Z converter we ever saw showed obvious signs of being overheated.

We have numerous dealers who use the same converters in the
supercharged/turbocharged systems they sell, and they have no
problems because they recalibrate the computer. Additionally, we use
the identical converter cores in the converters we build for a
variety of other vehicles (including those with turbocharged engines)
and don't have any problems. That's just an additional indication
that the problem is with the car, not our converters.

To eliminate the problem, we now offer converters with ceramic cores
for 350Zs that have not, or will not be retuned. The ceramic cores
don't flow as well as the metallics, so the mixture doesn't become as
lean. Unfortunately, many Z owners decided to post negative comments
before they even notified us that they had a problem, so it took us a
lot longer to find the cause and solution to the problem. I hope this
answers your questions.

Dave

 

bunch of BS.. I went up there a year ago in person and their response was "well, why did you bring them here?" They asked if I turned in the warranty card, then explained that something had to be wrong with my car cause their cats were perfectly fine..

They replaced them and they failed again 3 months later, I just decided to gut em and use them as test pipes. They knew this was an issue but denied it initially.. now a year later they're losing business and its the Z owners fault.. whatever.

 

Don't be hatin'...

 

+1. They lose our business due to their product failing then blame us. I thought it was the FI guys and the heavily modded NA guys that were having most of the problems. After reading the above message it would seem like only those who keep the stock tune would be having problems. Contradictory???

 

Mine collapsed at the track...I gutted them and used them for test pipes for a while . I didnt car for the rasp with them even when they were new

 

Mine failed N/A, I didnt want to take the chance with FI.. imagine all that backpressure going into the turbos if the cats fail? I would of been PISSED.

 

*** hf cats.....just get test pipes and if you live in a city that requires smog just switch back to the OEM cats for testing.