GMG Racing WC-EVO Long-Tube Headers for 991 GT3 & GT3 RS
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Being that these are completely modular, the headers are compatible with all side deletes and of course the factory side muffler as shown. We do believe the factory side muffler to be pretty restrictive, but imperative to keeping a certain comfort level for street driving. This was the goal with our headers from the beginning.
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BlazinPond (11-11-2019)
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[QUOTE=We do believe the factory side muffler to be pretty restrictive, but imperative to keeping a certain comfort level for street driving. This was the goal with our headers from the beginning.[/QUOTE]
Can you elaborate a little ore on this?
TY
Can you elaborate a little ore on this?
TY
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We will be posting weights shortly. Just waiting for a fresh pair of headers to come off the fab table![burnout](https://rennlist.com/forums/graemlins/burnout.gif)
Being that these are completely modular, the headers are compatible with all side deletes and of course the factory side muffler as shown. We do believe the factory side muffler to be pretty restrictive, but imperative to keeping a certain comfort level for street driving. This was the goal with our headers from the beginning.
![burnout](https://rennlist.com/forums/graemlins/burnout.gif)
Being that these are completely modular, the headers are compatible with all side deletes and of course the factory side muffler as shown. We do believe the factory side muffler to be pretty restrictive, but imperative to keeping a certain comfort level for street driving. This was the goal with our headers from the beginning.
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We will be posting weights shortly. Just waiting for a fresh pair of headers to come off the fab table![burnout](https://rennlist.com/forums/graemlins/burnout.gif)
Being that these are completely modular, the headers are compatible with all side deletes and of course the factory side muffler as shown. We do believe the factory side muffler to be pretty restrictive, but imperative to keeping a certain comfort level for street driving. This was the goal with our headers from the beginning.
![burnout](https://rennlist.com/forums/graemlins/burnout.gif)
Being that these are completely modular, the headers are compatible with all side deletes and of course the factory side muffler as shown. We do believe the factory side muffler to be pretty restrictive, but imperative to keeping a certain comfort level for street driving. This was the goal with our headers from the beginning.
I put mine back in to keep the noise down when cruising around. And I think they also have an impact on tone quality too.
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The easiest way to put it is that the runner lengths are hindered by the side mufflers. By using 3D scan technology, we were able to increase the runner length significantly and use all the space possible to maximize runner length without having to sacrifice the comfort of eliminating the side mufflers. This is also how we were able to fit them without and modification to the rear diffuser/under panel.
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^Thanks- finally some one who makes Catted LT headers that are modular.- Great job guys.
Can not wait to hear from those who jump on these shortly
May have to to buy Myself an Easter gift when Spring hits and pull her out of storage.
Can not wait to hear from those who jump on these shortly
May have to to buy Myself an Easter gift when Spring hits and pull her out of storage.
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Thanks for the recognition Jimmy D! This is why we build them this way, so we can offer different solutions for our clients.
Plus, I am starting to see a lot of our competitors units for sale from users who have said the system they installed is just too loud!
It's great for a weekend and/or a track day but it's just not livable on the street. Side mufflers certainly help manage that sound while giving you the options of opening and closing the valves.
The Headers are great for low end torque, which is very much needed on this car, and the rear Center Section gives you that glorious sound.
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Global Motorsports Group ™
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F: +1 (714) 432-1590
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We will be posting weights shortly. Just waiting for a fresh pair of headers to come off the fab table![burnout](https://rennlist.com/forums/graemlins/burnout.gif)
Being that these are completely modular, the headers are compatible with all side deletes and of course the factory side muffler as shown. We do believe the factory side muffler to be pretty restrictive, but imperative to keeping a certain comfort level for street driving. This was the goal with our headers from the beginning.
![burnout](https://rennlist.com/forums/graemlins/burnout.gif)
Being that these are completely modular, the headers are compatible with all side deletes and of course the factory side muffler as shown. We do believe the factory side muffler to be pretty restrictive, but imperative to keeping a certain comfort level for street driving. This was the goal with our headers from the beginning.
It aligns with my goals and current setup (Center bypass) yet keeping the side mufflers for cruising (for the wife).
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gmgracing (11-12-2019)
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The easiest way to put it is that the runner lengths are hindered by the side mufflers. By using 3D scan technology, we were able to increase the runner length significantly and use all the space possible to maximize runner length without having to sacrifice the comfort of eliminating the side mufflers. This is also how we were able to fit them without and modification to the rear diffuser/under panel.
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The thing that gets my attention is actually the lack of a big dip in the 5000-5500 rev range that I have seen elsewhere..
I am sure everything has a trade-off but I am no expert by a long shot
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On Dundon headers, the .1 GT3 and RS gets a significant drop in torque at 4800rpm that it doesn't make back up until 6000rpm.
But on their .2 GT3 and RS dynos, that drop doesn't occur and the graphs look pretty similar except Dundon has more top end gains.
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The easiest way to put it is that the runner lengths are hindered by the side mufflers. By using 3D scan technology, we were able to increase the runner length significantly and use all the space possible to maximize runner length without having to sacrifice the comfort of eliminating the side mufflers. This is also how we were able to fit them without and modification to the rear diffuser/under panel.