airboxes and silencers, too much crapolla,

[srxvmax50]

To this day I still cannot believe that a Vmax person should not rid their machines of workspace-clogged airboxes and suitcase-sized silencers as seen on the factory Vmax. I'm just gonna do it. Change it . Airboxes and carbs: I can figure that out.. Muffler: because of necessary backpressure, I need to determine the flow that goes thru the suitcase sized silencer, so that I can get rid of this excess weight . My intention is to measure the volume of flow thru the silencer, maybe using H-2-O as a standard then select stinger silencers that do the same. I plan on dyno'ing this engine thru the process. Contributions? MJD.

[Vmax540]

Heck, the silencer can't weight more than....... what..... 30-40 Lbs........ I thought of trying to carefully split one on the seam with a sawsall or cut off wheel and take a look inside. Maybe just mostly gut it, then weld it back together. I've read articles on pipes and how they are designed and shaped to scavange exhaust and provide a certain amount of back pressure. I'm not sure..... but, I believe the silencer is to far downstream to make any noticable difference except to silence the exhaust ?

[Donnie]

I'm not sure but I believe the silencer is to far downstream to make any noticable difference except to silence the exhaust ?

Ahhhhh, not true. I took my silencer off once thinking I would gain some power. Didn't work one bit. The sled couldn't pull itself around even without me on it. The clutch would engage and the motor just bogged. The more throttle you fed it, the weaker it got. I stuck the silencer back on it and I was lifting the skis off the ground again. I asked a racing buddy of mine at the time how the silencer worked and he didn't know, but he did say that S shaped stingers of the same diameter as the pipe ends would provide the needed pressure. I never made them for my Vmax. I will say that my sled sounded good at idle and up to engagement. Sounded FAST while sitting still... which is where it sat.... not moving.

Donnie

[Weasel]

The actual stingers are inside the muffler,, read some where it said, "do not run the engine without being connected to the silencer/muffler". Can't remember where I read that but here's a look at the stingers, Other pics are in my "pipe orientation" topic

[jefflanthier]

My air box is coming out i,m gonna put uni filters and rejet it to work. I,m tired of it being in the way of everything. Makes me mad when i cant sync my carbs without tearing half the sled apart. I also have AAEN pipes which some people dont like, but they run my sled just fine, as i,m not racing it . And they sound nice as well!

[Undertaker#13]

Maine you can't run Loud pipes on the trail. Noise is nice,but it's not Fast!! Stock pipes make's more horse power on these old Vmaxes

[91 Vmax sled]

I seem to be having some problem with this issue as well. My 1990 Vmax was recently all tuned up but I still have that bogging feeling and sound. It also seems like when I give it more throttle it gets weaker and just sounds even different from my other one that I have. I can get some good speed but most of the time it feels and sounds like it is hesitating.

Could this be cause from the "silencer" being plugged from somthing? My mechanic took it off from the pipes and it ran crappy then he put it back on and it seemed to be gone. I got it home and it seemed ok for about 20 minutes then the same thing happen again. Sometimes even if I am climbing a small incline (hill) it would bog out and I would have to get off and feed it gas off and on and with no wait on the sled to get it going.

So again I am asking do you think it could be the "silencer" has anyone had this same problem happen to them.

This seems to really have us stumped. Again the sound of the pipes don't sound the same as they used to and definitely don't sound the same as my other one which sounds great and the way this one used to sound.

Has anyone ever open the inside of a silencer or know of a way to clean one out in case there is somthing in it causing this fluxuation in back pressure which we think might be the problem here.

Again I am not looking at taking it off as I know it needs to be on for the proper back pressure but has anyone had this same problem

Thanks for the help

[Undertaker#13]

Never had a problem with my Vmax! Old Maximum Overdrive alway's hauls the mail! My sled never stumbles! Just when it runs out of gas almost at the finish line That sucked. If you take the can off it won't run because you will change the backpressure! I don't see what all the fuss is about? I have noproblem with the can or stock airbox

[srxvmax50]

Mr. Ottawa, if you do have a blockage in your exhaust, which you need to check, then yes you are suffocating your engine. You know, squirrrels and mice can wreak havoc in the off season, so check that alll out. As you explained your situaton It does sound to me like you got fuel handling problems, clutch shifting problems etc., and not pipe, but...start with the exhaust, because that is more straightforward, then go to the hard stuff.

[srxvmax50]

Weasel where is your pipe orientation project at. Never mind, I'll find it, and thanks for the pics. You is cool. Nevertheless, the bore of stingers embedded in a muffler is not necessarily useful to a tuner because it's part of a back pressure silencer package. And I wanna get rid of that heavy box. I wonder if one could determine volume flow thru the stock box, then duplicate this with lite wgt. silencers and pipe, then.. maybe we got something. I'm gonna see. (next winter?) MJD.

[Vmax540]

Like I said, "I'm not Sure"....... So, looking at Weasels pictures if these tubes/Stingers(?) are inside the silencer and provide the necessay back pressure then, maybe you could leave them and just, remove the rest of the baffles or what ever else is inside to lose weight and still be somewhat of a noise reducer ? Heck, I have 3 or four silencers laying around guess I'll have to cut one and take some pictures. I have one that is off a 81 SRX that someone cut in half and rewelded that is definately lighter and seems to work fine.

[Weasel]

The stinger I.D. and length is a major part to the pipe tuning for a perticular engine.
They are mostly a pressure relief valve and a very specific one at that. I would like to think that the silencer/muffler would be made as to not interfere with the pipes tuning
rather than being part of it. I could easily be wrong but my other hobby is RC Nitro racing boats,, world class equipment I assure you,, the silencers we run on our tuned pipes are designed and tested to not interfere the pipe tuning.

With that being said, if you go to Aaen and look at they'er "Aluminum Silencers" and read the lower portion of they'er instructional blurb it says, "cut 6 inches off your pipes stingers" when using those silencers. Appearently those type of silencers will act as part of the stingers function,, which sounds reasonable to my ears,, I guess I'm gunna find out in a fews months.

BTW, cutting the V-Max stock silencer apart is not fun, that thing is really put together. As I remember it was shaped like an "S", stingers were layed out diagonally goin' into the top front and a unobstructed S shape to a turned down exhaust exit at the bottom rear,as I remember it. There are sheets of perforated steel on the sides of the passage way with fiberglass like material behind them. I remember a thick chunk of plate steel in the bottom, probably for floor mounting,, or just excessive gravity

[Vmax540]

Weasel, Thanks for the information, very interesting..... we learn something every day !
"cut 6 inches off your pipes stingers" when using those silencers. Do you think they want you too use the stock stingers (shortened 6") from inside the silencer in addition to their aluminum silencer ?

[Weasel]

I would call Aaen and verify before I cut anything, just to be absolutely sure, it's that important. Do you notice the two stingers being different in the pics? One is "near" 1- 1/8th inches I.D. (for the pipe with extra bends) the other is near 1" I.D. The 1" one has a longer stinger too.

I would bet that it would be necessary to reverse my carbs since my pipes are flipped up-side-down. I was going to use EGT guaging in my buggy and I'm really going to use them now knowing how different the pipes are constructed. Gawd I wished I had used a different buggy engine, but who knows, could be a real bullet too.

[Weasel]

The actual stingers are inside the muffler,, read some where it said, "do not run the engine without being connected to the silencer/muffler". Can't remember where I read that but here's a look at the stingers, Other pics are in my "Jetting related to pipe orientation?" topic,,, and look what it says on the left side of the airbox!