Pipe numbers

[cbonner99]

Was just looking at some of the different engines and pipes available and got to wondering
What do the different numbers represent on the pipes? There are 056, 086, 1005, 2020 and many others. It there any industry standard for the assignment of the numbers and what are the benefits of one number over another?

[twigstoy]

Lots of companies make the same number on the pipes, but I do not think they are the same..Some pipes are for top, some bottom. some mid.. some pipes work better on certain engines. (Example) The 1005 you have is killer on the nova's especially the p5x line. The .086 is good for top. The 063 is bottom.. This does not mean they work great on all engines.. The best way I have found, is ask about the engines you have or are buying.. Maybe you won't have to spend money on a pipe..

[cbonner99]

Yeah but one persons opinion may be different than mine. I am just trying to gain some knowledge so I can make my own opinion. I know there are pipes for different engine rpm/torque ranges, but what numbers are for which range and what are the actual physical differences of the pipes?

[LUV DA AIR]

the numbers on the pipes and bodies are HOMOLOGATION numbers. they are numbers issues by a sanctioning body(usually IFMAR) in charge that is in AGREEMENT with other sanctioning bodies(ROAR, FEMCA, EFRA) and manufacturers to meet a certain detailed industry standard. That why you can get an RB 086 and an Ofna 086 pipe. It means the overall design, length, number of chambers, and exhaust tip length meet an agreed upon standard.

Silencers may be homologated by ROAR, EFRA or FEMCA up to four (4) months
before the event. Silencers homologated in the four (4) month period before the event
will not be included on the IFMAR Approved Muffler List for that event.