Edwardo said:
Malibu, that was a sweet video. Thank you for posting it. I would be very interested in hearing more about the exhaust.
What exhausts have you heard that are higher pitched than that? Gruppe M?
Really cool. Thanks!
The mufflers are kinda similar to GruppeM V3. However I believe in changing the entire system including headers for max effect. This is similar to the design I used on my last 911 back in 2001 which made it sound no longer like the typical Porsche sound. Malibu saw the video of my 911 in Sepang and it too had a very high pitch on approach but driving away had a lower pitch. On the 911 I gained 11% in BHP and torque measured on Gtech with a much flatter torque curve.
The headers were modified from the template of a Mugen header. The pipe diameter/length was adjusted for street (more torque in mid revs) and the lengths of the pipes made exactly equal. The crossover pipes are also equal length but fabricated on the car after fitting the headers and mufflers (catback) so it's not on the CAD yet but the factory could input it into the CAD and make a jig for it. They are connected to the headers via flexible pipes with flat insides (ie. not wavy inside) and reinforced with steel braiding outside.
The muffler is custom made straight through design similar to Magnaflow: thin layer of stainless steel wrapped around perforated pipe then chamber filled with mineral/glass wool. The muffler is mirror finished including the welds which become totally invisible. Its like a muffler made from 1 piece of metal. The mufflers could be designed differently for different loudness or shrillness or rawness or delete them for similar effect to the scorcery F1.
All pipes are stainless steel and I used 16 gauge for durability.
As for tailpipes, there is a selection in the factory of what looked like 60-70 designs from the mild to the bizzare
Building from scratch with CAD adjustments for length, building the jig and fitting cost about the price of one of the cheaper headers/muffler combo without cats. Producing them now would definitely be cheaper than the lowest cost system available anywhere but their build quality is really good.
Some kinks that need to be ironed out for those into aesthetics:
1)The pipes are not polished to a mirror finish, might cost more to polish them.
2)the pipes turned matt blackish in colour after some heavy use on the track so i need to find out why this is so but there is no signs of corrosion even though its been used frequently in tropical rains and muddy conditions.
3) There's no space for stock cats so will have to replace with sports cats if cats are required
4) If muffler hanger points are different on later model cars then I wouldn't know where to put them unless I have data or a guinea pig car
5) Exhaust note is too quiet when new IMHO but starts to really "breathe" after some usage with a more complex sound with more harmonics
6) You can't hear the exhaust from the cabin at idle and outside it is as quiet as stock though it sounds very very sweet on startup from cold like as though it is idling at 2500rpm but its not (dont know why) but once engine is warm idling is very quiet even outside the car
I was opening bottles of JW Green Label everywhere and you can get it in some really cool clubs for $40. I even got a free JW Green long sleeve polo for ordering it at a club called Booze. JW pushes a really low price for their product to start the addiction there.
Nice NSX too <B>Pzull</B>. Great to see some video's being posted.
