GPR race exhaust

[waspp]

I just came across this ebay store which sells various hand built "race exhaust" and see they have several systems for Guzzi's. The 2 into system for the V11 is offered for $700 which considering its a whole sytem doesn't seem bad. Has anyone here had any dealings with these folks, or have one of their systems, I see they also offer a competition ecu as well.

 

http://cgi.ebay.com/ebaymotors/ws/eBayISAP...;category=35619

[Skeeve]

I just came across this ebay store which sells various hand built "race exhaust" and see they have several systems for Guzzi's. The 2 into system for the V11 is offered for $700 which considering its a whole sytem doesn't seem bad. Has anyone here had any dealings with these folks, or have one of their systems, I see they also offer a competition ecu as well.

 

http://cgi.ebay.com/ebaymotors/ws/eBayISAP...;category=35619

 

Not a good idea, converting the V11 to a 2->1 exhaust, with one can approx. the volume of one of the stock cans. Too much restriction, unless the can is simply hollow, then it's just too much NOISE!.

 

Big twins like big [exhaust] volume. This is one of those things the H-D crowd just never seem to "get," & keep putting on either stupidly loud drag pipes or skinny "chopper" pipes.

[Tom M]

Not a good idea, converting the V11 to a 2->1 exhaust, with one can approx. the volume of one of the stock cans. Too much restriction, unless the can is simply hollow, then it's just too much NOISE!.

 

Big twins like big [exhaust] volume. This is one of those things the H-D crowd just never seem to "get," & keep putting on either stupidly loud drag pipes or skinny "chopper" pipes.

 

 

Someone get Guareschi on the phone! He needs to know this!

 

 

(photo from http://guzzitech.com/PHPBB2/viewtopic.php?t=110)

[Skeeve]

Someone get Guareschi on the phone! He needs to know this!

(photo from http://guzzitech.com/PHPBB2/viewtopic.php?t=110)

 

Thanks for making my point, Tom. That's not really a muffler, and if you tried running your v11 w/ that open megaphone Gianfranco's using you'd get a ticket for disturbing the peace in pretty short order, I'm sure!

[Paul Minnaert]

well that same quat d comes for the breva/griso with all papers for road use:-) and sounds like this:

 

http://au.youtube.com/watch?v=2h2DOz2TIOc

[GuzziMoto]

As far as noise goes, a well designed 2 into 1 system can be just as quiet( or quieter) as a 2 into 2 system. Believe it or not a well designed collector acts as a muffler, lowering sound levels. We used to run a custom made 2 into 1 pipe on our Harris chassis Ducati and it was quieter with the collector then with out(by a lot). And not only the new Guzzi's are all 2 into 1's(probably in part due to the noise issue), but so are Buells. In fact Buells have very well designed 2 into 1's that are quiet and make great power. And most noisey H-D are not 2 into 1's but straight pipe 2 into 2's so that does not support your case.

I was not a 2 into 1 fan until we tested them for our race bikes and found that a well made 2 into 1 made more power. I'm now a believer. But they are not all created equal. Some make more power then others. Ours were custom made by a local guy in Maryland that mostly does race cars(NASCAR and Dragsters). He takes things like head flow and cam timing and builds each pipe for each motor. Has done at least one Guzzi pipe a long time ago for an old friend of mine named Dave. If you prefer the look and sound of a 2 into 2(or a 2 into 1 into 2), that's fine, but if you want max power( and I must admit, I have grown to love the sound. It's a little more of a growl. The individual pulses blur together instead of sounding like two singles in unison) a 2 into 1 is the way.

[Skeeve]

As far as noise goes, a well designed 2 into 1 system can be just as quiet( or quieter) as a 2 into 2 system. Believe it or not a well designed collector acts as a muffler, lowering sound levels. We used to run a custom made 2 into 1 pipe on our Harris chassis Ducati and it was quieter with the collector then with out(by a lot). And not only the new Guzzi's are all 2 into 1's(probably in part due to the noise issue), but so are Buells. In fact Buells have very well designed 2 into 1's that are quiet and make great power. And most noisey H-D are not 2 into 1's but straight pipe 2 into 2's so that does not support your case.

I was not a 2 into 1 fan until we tested them for our race bikes and found that a well made 2 into 1 made more power. I'm now a believer. But they are not all created equal. Some make more power then others. Ours were custom made by a local guy in Maryland that mostly does race cars(NASCAR and Dragsters). He takes things like head flow and cam timing and builds each pipe for each motor. Has done at least one Guzzi pipe a long time ago for an old friend of mine named Dave. If you prefer the look and sound of a 2 into 2(or a 2 into 1 into 2), that's fine, but if you want max power( and I must admit, I have grown to love the sound. It's a little more of a growl. The individual pulses blur together instead of sounding like two singles in unison) a 2 into 1 is the way.

 

You've missed the point. I have nothing against a 2->1, in fact, I would favor them, since 1 large can will usually weigh less than 2 smaller ones. I was only pointing out that the VOLUME needed for an effective muffler [we're discussing street-legal applications here, not race cans] just was not visible in the link to the ebay vendor that started this thread. In fact, the "race exhaust" sold by that vendor appeared merely to be the standard exhuast with a 2->1 collector feeding into one of the unnecessarily restrictive [see the thread on dissecting the stock cans] stock mufflers.

 

The point being, I think, that a healthy dose of "caveat emptor" is in order when dealing w/ some no-name eBay-only seller w/ a "race exhaust" of unknown provenance.

[GuzziMoto]

That muffler in the E-Bay ad is larger then the Quat-D that I was running on my Griso. And that was a pretty quiet system. One of my points is that you do not need double the muffler volume if you switch from a 2 into 2 to a 2 into 1. You can actually get away with the same size or even smaller. Muffler size is more related to the displacement of one cylinder since only one is exhausting at any given time. And a 2 into 1 diverts some of the exhaust energy back up the other header so there is even less exhaust energy to quiet down. The only thing that scares me is I would want to see a pic of the collector before I laid down that much coin. 2 into 1's are very dependant on the design of the collector. The newer style merge collectors(they're really not that new, cars have been using them for years) are sweet. But I've seen too many collectors on bike exhausts that are just two pipes cut and welded together with no thought about flow.