Gents, I am a newbie to this forum, so any help would be greatly appreciated. I have a early Euro spec F355 (2.7 engine). I also have a Tubi Pipe Only exhaust system (similar to a Spa Challenge system). I have been told that the cats have blown out, and are now hollow. My questions are: What would the effect of replacing the worn cats with test pipes be? Would I lose too much back pressure with this i.e. pipe only Tubi and worn cats/test pipes?? Should leave the cats as they are, or replace them? Thanks in advance, Roger.
dump the cats and get them rebuilt for when you sell. Your car will be much happier w/o them. I used to get check engine lights all the time. turns out one of the cats was completely gone and plugging up the gas flow. I bet I was losing 15HP from that cat problem. Engine bay temps will drop, and I believe that the cats contibute to header failure (I could be wrong). Get rid of them. Install straight pipes and a tubi (or other aftermarket muffler of your choice). If its too loud get the silenced cat bypass pipes to take out some of the harshness. You should be happy with the results
