not our body style but still on the same cars. this can show a trend between muffler desings. I have seen one on the newer body style but I can't find it. should have bookmarked it.
the other I remeber bassani, magnaflow and borla where on top. I think bassani had the best hp but borla had the best torque.
the chambered stuff like mac and flowmaster where not too far behind.
I remember seeing one quite some time back.....Magnaflow and Borla blew away all the others in the comparison....The car was a old fox body....headers, can't remember what else....I remember many of the others produced close to the same amount of peak power-but magna and borla gave much more power throughout the entire rpm range.....
When I saw the comparison there was 2 race mufflers that were #1 and #2 I want to say #2 was some dynomax muffler then the Borla XS mufflers were #3 and Magnaflow was #4 cant remeber after that but they did like 10-15 different ones.