GSXR Exhaust

[ameen]

I just purchased a GSXR exhaust for $20 and was thinking of adding it to my gs500.  I am not sure what bike it came off of but it definitely looks like it will flow a lot better than stock (i hope at least).

The can has a 4 bolt flange where i need to fab something up to connect to.  Anyone here do this already?   I  found a couple results when i searched, but not too much.  I may have my brother cut something to spec with a water jet.  Im not a machinist, anyone know how big the hole should be made in the adapter to weld to the stock GS mid pipe?

Thanks,
Ameen

[The Buddha]

If you got it with a short length of the header, you can cut yours and slide it on and weld.
Else you're gonna have to make a plate and drill and weld that plate on.
I got some 3 bolters lying about, sorry no 4's AFAIK.
Cool.
Buddha.

[Chanse]

+1 with da buddha

[ameen]

unfortunately i just have the can, no pipe piece.  I am going to get an adapter made. How big is the OD of the GS pipe? I know its about 2 inches, but is that exact ( i dont have a caliper)?

Im really curious how this will sound on the GS.  I am not really a fan of loud pipes, but we'll see what happens.

[kml.krk]

been there, done that.
Sounds exactly the same as stock exhaust. Flows a tiny bit better but it's not a straight-through pipe so don't get K&N lunchbox for it.

I had my flange custom made from 5mm steel plate. I made an outline in cardboard and transferred it to the plate then using simple tools like drill and dremel I got it all done. No need for fancy CNC but it will make things a lot easier if you have access to such tools.

If you want to see how it looks I can find some old pics for you. I have 04 GS with fairings.

I eventually changed the pipe to 05 GSXR Leo Vince SBK. Since I had the flange already done and welded to my midpipe it was just a matter of bolting it on.
Leo flows as much air as you can get from GS, it's straight-through pipe with no restrictor.
In my opinion it sounds great too!
If you want I have video/sound clip of it on youtube: http://www.youtube.com/watch?v=tx8_EsjAzx4

Please use some headphones when you listen to the sound. Laptop speakers just don't do the justice 

best of luck to you
KML

[007brendan]

Anything other than stock is going to be fairly loud.  Not harley loud, but loud just the same.  I had an exhaust for a mid 90s I4 honda that I just took to an exhaust shop and they were able to fabricate and weld a midpipe, and clamp on the can for $85

[gregvhen]

even if it is only a slightly better flow, having the flange adapter will let you bolt on an aftermarket gsxr exhaust (which is way more common then AM gs exhaust) in the future if you ever decide to do so

[ameen]

So, should how much better flow should i be expecting?  Would it or would it not make it worth it to upgrade the air filter?

I know it is not straight through but the hole is friggin huge compared to what is on the GS

[kml.krk]

is it stock GSXR exhaust we are talking about? do you have pictures?

it doesn't matter how big is the 'hole'. What matters is how the muffler is build internally (baffle) and how tight the packing is inside (usually fiberglass packing).

cheers
KML

[gregvhen]

is it stock GSXR exhaust we are talking about? do you have pictures?

it doesn't matter how big is the 'hole'. What matters is how the muffler is build internally (baffle) and how tight the packing is inside (usually fiberglass packing).

cheers
KML

and how big the tubes between the chambers are

EDIT: and the chambers themselves

[ameen]

It is the stock muffler from a GSXR (i dont know what displacement).  I figured that the GSXR moves substantially more air than the GS so the muffler should have a higher flow rate. 

The tube between the chabers is pretty big (i would say roughly 2 inches diameter) from looking in the bottom end of the can.  I don tknow what year it is from either but it is a 4 bolt bolt on model and is HUGE.  Much longer and wider than the stock GS.  I could get some pictures tonight.

[gregvhen]

It is the stock muffler from a GSXR (i dont know what displacement).  I figured that the GSXR moves substantially more air than the GS so the muffler should have a higher flow rate. 

The tube between the chabers is pretty big (i would say roughly 2 inches diameter) from looking in the bottom end of the can.  I don tknow what year it is from either but it is a 4 bolt bolt on model and is HUGE.  Much longer and wider than the stock GS.  I could get some pictures tonight.

you cant tell how big the internal tubes are though from looking at the end. only the last tube, but i would agree with you about the flow, that is i too would think that it would be built to pass more air then a gs

[kml.krk]

it does move more air but not as much that you could fully utilize K&N Lunchbox.
I know exactly because I fell in the same trap.
I bought Lunchbox, GSXR exhaust, and larger jets. Turned out that the air intake was larger than output and bike ran like sh!t.
I drilled holes in back of the muffle, and it run like crap and sounded like... Oh My God... disaster.

I ended up buying Leo Vince SBK, which solved all air flow issues. It sounds great and provide maximum air flow.


I am not trying to tell you not to use GSXR exhaust, I am just warning that the result may not be what you would expect and it may be hard to jet properly.
If you are looking for maximum power than your air intake should match air outflow, and you need proper jets so your mixture is rich enough.

Good luck,
if you plan to rejet search the forum first, if you still can't find answers then ask away 

[jeremy_nash]

it is going to sound exactly the same as the stock gs exhaust.  it will look different.  that is all.  I did the same thing with an exhaust for a r6, and it was QUIETER THAN STOCK