| Author | Message | ||
| Rob Schermerhorn (Rexrcr)
Member Username: Rexrcr Post Number: 512 Registered: 11-2002 |
Manu, you're right about the resonators. | ||
| Manu (Manu)
Member Username: Manu Post Number: 698 Registered: 2-2002 |
Rob Lay - in answer to your question mate... I don't know the answer and was hoping RXCR could help us out... With reference to the so-called cat-bypass channel for the exhaust flow - (the upper channel) - obviously the exhaust flow passes through the diagonal pipes.... Well take a close look at the two pipes....BASICALLY IS the increased diameter (from the very beginning central inlet) allowing for the two diagonal pipes to give a type of 'resonation' chamber effect...muffling the noise slightly. On 'conventional' straight exhausts, the increased diameter is the mark of a 'resonator' - is this the case here and if this was eliminated - and the pipes were smaller and of continuous diameter, would I be right in saying that car would be even louder? | ||
| Rob Schermerhorn (Rexrcr)
Member Username: Rexrcr Post Number: 498 Registered: 11-2002 |
See the color difference between the outboard and inboard. Catylists. | ||
| Rob Schermerhorn (Rexrcr)
Member Username: Rexrcr Post Number: 497 Registered: 11-2002 |
This reminds me: if you go through impound and they subject you to a sniffer test gas analyzer, make certain that the probe is placed in an inboard tailpipe. The outboard ones don't go through a catylist! I had to do this a couple times in '98. | ||
| Rob Schermerhorn (Rexrcr)
Member Username: Rexrcr Post Number: 496 Registered: 11-2002 |
LOL Not wrong, learning! This is a photo of OEM Ansa F355 Challenge exhaust system. There are silencers for the "third" exhaust branch. Otherwise, it's just up to the catylist for sound damping. Yes, very loud. I only had to change to the "quiet" Challenge exhaust at Blackhawk Farms Raceway in Roscoe, Illinois for sound violation. We blew 105 dB. The quiet system (which resembles the OEM street exhaust) was only 96 dB. We ran the "open" system at Road America, Mid Ohio, Gingerman with no sound problems. Just make certain you own a quieter muffler for the possibility of sound violations. BTW, love the sound of this system. Rob | ||
| Rob Lay (Rob328gts)
Board Administrator Username: Rob328gts Post Number: 4377 Registered: 12-2000 |
Is there even a muffler on that thing? Are those 100% straight pipes. No wonder it's so loud. The SCCA won't allow them even and they allow 103 Db from 200 ft. or something like that. I heard the Challenge exhausts are up above 107 Db. I'm sure Rob will provide the facts. I'm always wrong on my 355 Challenge stuff so far. | ||
| Manu (Manu)
Member Username: Manu Post Number: 697 Registered: 2-2002 |
Those of you who own the F355Cs (or indeed are familiar with them).... Which type of exhaust system do you have fitted to your cars - which do you like better FROM A SOUND POINT OF VIEW? (not that this is a primary concern on a racecar). Any of you have (or have you heard) the super-loud Challenge "spa" system and do you like it? See picture attached below:  |