Dundon Motorsports 991 GT3/RS Street (Catted) Header Group Buy
10-31-2016, 01:55 PM
#46
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An easy fix to it is to modify the intake and exhaust cam timing to a more performance oriented setting, this requires a tune and very few folks are going to tune their GT3 and RS until they're out of warranty... We are working with Cobb to try and get their system available for the GT3 and RS, would allow for easier DIY flashing, logging and code reading and clearing. Reach out to them and let them know you'd be interested to push it along.
you can reach Mitch at
mitch.mckee@cobbtuning dot com
We've tested a number of exhaust configurations that can reduce this flattening of the HP curve, but they also reduce the gains everywhere else.
When you drive the car this is typically an area that you are part throttle (at least I am and hammer it around 6k anyway). The car pulls strong and you don't feel the HP flattening, this is because if you look at the graph the HP is delayed about 500 rpm before it starts climbing steeply, so you're butt doesn't have time to truly react.
We try to be as transparent as possible, most companies would have said there are 30lbft gains and 32whp and that would be that. We want you to know what's there and what you're getting!
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Dundon Motorsports
Gig Harbor, WA
253-200-4454
jamie@dundonmotorsports.com
www.dundonmotorsports.com
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Dundon Motorsports
Gig Harbor, WA
253-200-4454
jamie@dundonmotorsports.com
www.dundonmotorsports.com
Facebook.com/dundonmotorsports
Instagram @dundon_motorsports
10-31-2016, 07:47 PM
#49
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There's a confluence of things going on to cause this, we believe. First thing to understand the is the engine is governed by emissions first, performance second. To that end the engine is setup to have exhaust gas reversion or recycle from the factory, this means that the exhaust gasses are momentarily flowing backwards (reverse) to try and keep some of them in the cylinder. By burning a portion of the exhaust gas over and over again NOx emissions are reduced. This is governed by the cam timing, the pressure waves in the intake and the pressure waves in the exhaust. If the pressure waves in the exhaust are stronger than the pressure waves in the intake and the cam timing is such that both intake and exhaust valves are open at the same time, the gasses will flow towards the intake and less fresh air can get into the cylinder.
An easy fix to it is to modify the intake and exhaust cam timing to a more performance oriented setting, this requires a tune and very few folks are going to tune their GT3 and RS until they're out of warranty... We are working with Cobb to try and get their system available for the GT3 and RS, would allow for easier DIY flashing, logging and code reading and clearing. Reach out to them and let them know you'd be interested to push it along.
you can reach Mitch at
mitch.mckee@cobbtuning dot com
We've tested a number of exhaust configurations that can reduce this flattening of the HP curve, but they also reduce the gains everywhere else.
When you drive the car this is typically an area that you are part throttle (at least I am and hammer it around 6k anyway). The car pulls strong and you don't feel the HP flattening, this is because if you look at the graph the HP is delayed about 500 rpm before it starts climbing steeply, so you're butt doesn't have time to truly react.
We try to be as transparent as possible, most companies would have said there are 30lbft gains and 32whp and that would be that. We want you to know what's there and what you're getting!
An easy fix to it is to modify the intake and exhaust cam timing to a more performance oriented setting, this requires a tune and very few folks are going to tune their GT3 and RS until they're out of warranty... We are working with Cobb to try and get their system available for the GT3 and RS, would allow for easier DIY flashing, logging and code reading and clearing. Reach out to them and let them know you'd be interested to push it along.
you can reach Mitch at
mitch.mckee@cobbtuning dot com
We've tested a number of exhaust configurations that can reduce this flattening of the HP curve, but they also reduce the gains everywhere else.
When you drive the car this is typically an area that you are part throttle (at least I am and hammer it around 6k anyway). The car pulls strong and you don't feel the HP flattening, this is because if you look at the graph the HP is delayed about 500 rpm before it starts climbing steeply, so you're butt doesn't have time to truly react.
We try to be as transparent as possible, most companies would have said there are 30lbft gains and 32whp and that would be that. We want you to know what's there and what you're getting!
11-15-2016, 11:28 PM
#51
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GT4 headers are getting through production, still waiting for the cats to arrive, we're pushing to have all catted system orders finished before the end of December!
12-06-2016, 10:16 PM
#54
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Same here Jamie. Will the catted headers be ready before Christmass? Just if I should leave some room under the Christmass tree ��..
Best regards. Anyhow we are all patient!
Best regards. Anyhow we are all patient!
12-06-2016, 10:27 PM
#55
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We're getting on them as soon as the cats arrive. We're going to prototype a few enhancements while we're waiting to try minimize that midrange dip!
12-10-2016, 09:12 PM
#56
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The initial group buy of GT4 headers is complete! We're moving to 991 catted next, we're still waiting for the cats to arrive and the 3" tubing we ordered 10 weeks ago. We're pushing our suppliers to figure out what's going on...
We should know more this week. Just to confirm all that are on the list
Group Buy List:
1. Asco, deposit paid
2. Asco, deposit paid
3. Farisad
4. Ibssam, deposit paid
5. Rob2368 deposit paid
6. RajDatta?
We should know more this week. Just to confirm all that are on the list
Group Buy List:
1. Asco, deposit paid
2. Asco, deposit paid
3. Farisad
4. Ibssam, deposit paid
5. Rob2368 deposit paid
6. RajDatta?
Do you think we could get the headers mid Jan?
01-04-2017, 10:05 PM
#59
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Hi Guys, finally hearing back from the mfg for the cats, they're supposed to ship middle of January. In the mean time, we haven't been sitting on our hands, we're trying a few tweaks to the design to see if we can make some more gains!
Will have some results by middle of next week...
Sorry for the delay and thank you for your patience!
Will have some results by middle of next week...
Sorry for the delay and thank you for your patience!