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* Muffler shown is not included with the system, only to see how the systme goes together!
The Dundon 991 GT3, 991 GT3RS and 911R Long Tube Street Header Exhaust System on 991 GT3 make
31whp at 8200rpm and
25lbft gains at 4600rpm
Dundon Convertible Street (Catted) tuned length headers and valved side delete exhaust system for the 991GT3 991 GT3RS and 911R are available now! We were able to keep all of the things that people love about our race headers:
- less weight
- more power,
- great sound,
- quiet when you want it to be
- no drone
- lifetime structural warranty
- 100% 30day money back guarantee
- if you try it and don't like it, send it back we'll give you your money back!
- Convertible to no cats with the swappable test pipes for track days (available separately).
We use 321SS (a superior grade of Stainless steel to the cheaper 304SS) and use a metal core spiral wound 200CPSI catalytic converter. All our products are mfg in the USA in our shop in Gig Harbor, WA.
By routing the primaries up and positioning the catalytic converter more vertical we were able to retain 99% of the primary length of the race system. This is how we are able to achieve 30whp gains on the 991 GT3 and 32whp on the GT3RS. This is the most power from a catted 991 GT3 Exhaust, 991 GT3RS Exhaust or 911R Exhaust system.
The Dundon Street Headers on 991 GT3 make
30whp at 8215rpm
26lbft, 23whp gains at 4586rpm
The Dundon Street Headers on 991 GT3RS and 911R make
32whp at 8400rpm
29lbft, 24whp gains at 4478rpm
The 991 GT3 and RS with the catted system shows it's emissions based camshaft tuning for about 5100-6000rpm area. This stock tuning flattens the power delivery for about 400rpms and then climbs quickly starting at 5400rpm. This is completely fixable with a tune, but understand that many will not want a tune.
You get everything you love about the Dundon Race Headers, 321 SS construction, industry leading power, lifetime structural warranty, and 100% money back guarantee, if you try it and don't like it, send it back we'll give you your money back!
To that end, see the dyno below!
991 GT3 Dundon Street (Catted) 434whp peak
991 GT3 Dundon Street (Catted) System vs Stock
991 GT3 Dundon Street (Catted) 26lbft and 23whp at 4500rpm
991 GT3 Dundon Street (Catted) vs Stock, 26wtq and 23whp at 4500 RPM
991 GT3 Dundon Street (Catted) 30whp max gains
991 GT3 Dundon Street (Catted) 30whp max gains at 8215RPM
991 GT3RS Dundon Street (Catted) 445whp peak
991 GT3RS Dundon Street (Catted) 445whp
991 GT3RS Dundon Street (Catted) 29lbft and 24whp at 4478rpm
991 GT3RS Dundon Street (Catted) 29lbft and 24whp
991 GT3RS Dundon Street (Catted) 32whp max gains
991 GT3RS Street (Catted) 32whp max gains
Some pics installed on the car, the street headers are only about 0.5" shorter than our race headers. To fit everything we had to go up into the wheel well where the side mufflers sit. Only way to get the length required for real power gains...
Dundon 991 GT3/RS Street
Dundon 991 GT3/RS showing length of primaries and routing required to fit the cat
Dundon 991 GT3/RS showing length of primaries and routing required to fit the cat2
As you can see to get the length we wanted we had to go up, anything that can bolt up to the stock location is leaving power on the table...
Video from the dyno so you can see and hear the awesomeness! You also get a good shot of how the headers are routed with the wheel off!
Dundon Street Headers on 991 GT3 - YouTube