Variable exhaust diameter

[Philly]

Hi all,

I was just wondering if anyone has done any research or gone even further in variable exhaust technology

I know a few current Suzuki motorcycles employ SET(suzuki exhaust tuning) which is basically a butterfly valve operated by a computer controlled servo motor. It is located in the downpipe of a 4-1 system.
Yamaha have had there EXUP system for years also.

I believe that it benefits low and mid range torque by sort of varying the diameter of the pipe on the fly.

Has anyone got any more info on this technology. Havent been able to find much on it yet.

Cheers,
Phil

[BMH]

heres one link I found that has a picture of it. Apparently this idea isn't new as Honda and Yamaha both have something similar.

http://www.mcnews.com.au/NewBikeCatalogue/2001/Suzuki/suzukigsxr1000page2.htm

Wiki says the SET is a device fitted to Suzuki engines that constantly adjusts the internal diameter of the exhaust system to perfectly suit engine revs. This ensures massive low to mid-range performance for a linear power output all the way to the rev limiter.

[ad]

im pretty sure TU Graz had one along with a variable intake runner, but im also sure the latest lambo has one before the entry to the muffler on both sides of their dual exhaust system.

[Diablo_niterider]

TU Graz had a butterfly on the exhaust just before the muffler... the car participated in fsg07

[Diablo_niterider]

have a picture dnt know how to upload , tell me how and will do it

[Dennis Seichter]

Yep, Graz had such a system in FSG07. They found the gap in the rules and used it - kudos for that.

However, they had to go to scrutineering again after the endurance, as their exhaust was significantly louder with the valve open. During the noise test, they had it closed, of course. http://fsae.com/groupee_common/emoticons/icon_wink.gif That's why there's this new rule item stating that all valve devices in the exhaust have to be set to fully open during the noise test now..

[Philly]

Wow. Great to hear there has already been teams doing such great things.

Sorry but who is TU Graz? Is it a University/person?

I wouldnt mind getting some contact details.

Cheers,
Phil

[Dan Deussen @ Weber Motor]

TU Graz = Technical University of Graz in Austria

Their car has a funny name: TANKIA = There Are No Kangoroos In Austria

Im sure if you google that you should find them!!!

[TG]

Originally posted by Dan Deussen @ Weber Motor AG:
TU Graz = Technical University of Graz in Austria

Their car has a funny name: TANKIA = There Are No Kangoroos In Austria

Im sure if you google that you should find them!!!

Austria! Well, then. G'day mate! Let's put another shrimp on the barbie!!

... sorry, couldn't resist.

I didn't know about that little trick TU Graz employed. That's pretty cool. And I wouldn't call it finding a loop hole in the rules either... there plain just aren't any rules about the exhaust outside the noise regulations and safety measures.

[Ian M]

Austria (not = ) Australia

but I am sure a lot of us got a good laugh over the mistake.
We shared TU Graz's tent and let them store their car in our trailer at night at FSAE (Mich.) last year.
Their car was pretty unbelievable, and they were a great group of guys. I believe they were running a sleeved 650 BMW engine if I remember correctly.

[Poe]

I guess you've never seen the movie "Dumb and Dumber"

[samphlett]

This isn't the first time I've witnessed a Yank not know that Austria and Australia are different places.

When living in America a few years back there was a news report about a pipe bomb in a hotel in Austria. The news reporter said "Australia" and then introduced the clip: mountains, snow, loads of signs in German, stern looking people. After the clip he repeated his error: "Scenes today from Australia. In other news..."

[Dan Deussen @ Weber Motor]

Originally posted by Ian M:
Austria (not = ) Australia

but I am sure a lot of us got a good laugh over the mistake.
We shared TU Graz's tent and let them store their car in our trailer at night at FSAE (Mich.) last year.
Their car was pretty unbelievable, and they were a great group of guys. I believe they were running a sleeved 650 BMW engine if I remember correctly.

There are actually two teams from Graz. TU Graz and FH Joanneum Graz. The guys with the single cylinder engine are the FH Graz teams.

The use of an exhaust flap indeed appeared to the Formula Student Germany organization as a loophole in rules. We actually have a few extra rules for the German event. One of them states that exhaust flaps must be fully open when performing the noise test. The main reason why we added the rule is due to the way events at the Hockenheimring are classified. The classification for all event held there is made by the amount of noise is produced by it. Currently the Formula Student Germany event does not even fall into any classification because the amount of noise we produce is low enough. This means we don't have specified time slots for our dynamic events. We can pretty much have running engines all day and all night. So if we don't do anything about teams that have exteremly noisy cars maybe next event they will actually put us in a class with limited run time which would be a huge disadvanted for all participants. Another aspect is the financial side. Non-classified event events are quite cheap to book at the Hockenheim Ring. For events with a noise classification there are only ceratin budgets available for the amount of days per year. So basically what it boils down to is: The louder your event, the more expensive it is to book at the Ring.