exhaust question

[truckinduc]

After i finish my swingarm and frame ill be building my exhaust. 1 5/8 primary tubes collecting into a 2 1/4 tube at equal lengths, 24 inches.  All out of 304 stainless.

Please make apparent the advantages, / dis-advantages with going with a 2 into 1 setup like i will be doing.

Also make apparent the advantages, / dis-advantages with going with a dual setup with an equalizer pipe.

Im still in the design stage so im open to concepts and ideas.

Thanks

[Drunken Monkey]

Possible more midrange and less top end with a 2-1...

Basically a 2 into 1 into 2 is going to flow slightly more than a 2-1, but the changes are small enough that you probably won't notice.

Nice graphs of flow requirements can be found here:

http://www.moto-one.com.au/performance/900monsterexhaust.html

[brad black]

i've never seen anyone do any sort of real testing to find the answers you're looking for.  usually because people want someone to give them the answers for free so to speak.  it just never happens.  and often those who make their own exhaust don't or won't get them dynod or tuned properly so there's never any evidence of how they work apart from "feels great", which is what everyone says in comparison to std mufflers.

i have a guy who emails me quite a bit from sweden who made a 2-1 that appeared to work as well as a set of slip on mufflers on std header.  i think he expanded both headers from 40 to 50 or so mm before the collector then ran a 50mm collector.  don't know if it was a critical point or not.

i'd mimic the original header design as much as possible in whatever style you want - it seems to work really well.  i think you'll find style and practicality outweigh any other considerations when you're making it.  i'd use a proper collector with 2-2, the equaliser pipe doesn't work ime.

[clubhousemotorsports]

I want to say that Doug Lofgren has dynoed 2-1 pipes and compared them check his site out
it is in the 2 valve stuff section .

Hey if you are going to build them build both and then have them dynoed, you tell us!

[truckinduc]

where is the 2 valve stuff section?

[clubhousemotorsports]

where is the 2 valve stuff section?

Here

http://www.visi.com/~moperfserv/report.htm