Dundon 718 GT4RS Development Thread. Input wanted!
#31
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- More Power, less weight, Weissach Style Tips, eliminate GPF
- 20" x 9" front wheels
- 20" x 9" front wheels
#32
Burning Brakes
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The Dundon headers/OAPs remain the best aftermarket tune available for the GT4, so I have little doubt they will deliver the same with the RS. Similarly, if Dundon sticks with the header/OAP combo they have for the GT4, the GPF will be gone with the RS.
No comment on the front wheels, other than to say I think the RS wheels are beautiful. I suspect your desire in different wheels is more performance-related?
Avera
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Odin (01-08-2023)
#35
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The rear muffler on the 4RS is the same as the GT4 with the exception of moving the path split to the muffler on the 4RS...…expect same sound.
Also, another vendor already confirmed that the internal passages of the 4RS muffler are smaller than the 992 GT3 while using the same engine with longer exhaust plumbing.
It's no secret that a muffler rear section on the GT4 produces power (not a lot) and we could assume that will be the same with the 4RS.
If a muffler is develop I'm pretty sure it can be used on both cars.....
The OEM manifold and OAP is a different arrangement from the GT4.
If you ask me to guess, we will have the same problems on the 4RS as on the GT4...of the 3 sections that can be swap, pick 2 or risk getting lots of drone and being too loud.
If there was a way to package a GT3 muffler internal design into the GT4/4RS step muffler design that would be great
Also, another vendor already confirmed that the internal passages of the 4RS muffler are smaller than the 992 GT3 while using the same engine with longer exhaust plumbing.
It's no secret that a muffler rear section on the GT4 produces power (not a lot) and we could assume that will be the same with the 4RS.
If a muffler is develop I'm pretty sure it can be used on both cars.....
The OEM manifold and OAP is a different arrangement from the GT4.
If you ask me to guess, we will have the same problems on the 4RS as on the GT4...of the 3 sections that can be swap, pick 2 or risk getting lots of drone and being too loud.
If there was a way to package a GT3 muffler internal design into the GT4/4RS step muffler design that would be great
#36
Burning Brakes
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Louder than anything I have heard that is not straight-piped.
Delivers more TQ/HP gains than any aftermarket tune available.
OEM rear box manages drone/resonance impeccably with decent tone.
I threw on the JCR Race Pipe to get that straight-piped decibel level and RSR tone. I got both in spades . . . along with the most unbearable drone/resonance imaginable. I crossed the line and the OEM rear box is back in its place.
So, as to the 5% . . . I have been holding out hope Dundon could deliver the rear box solution myself and many other Dundon header/OAP owners have been hoping would become available. Unfortunately, @Ted@dundonmotorsports sounds less than optimistic Dundon can deliver a small miracle.
Given the RS has the exact same chassis as the GT4, I do not THINK the fact it has a different engine is going to alter the scenario significantly, if at all. If one chooses to go with Dundon headers/OAPs, the OEM rear box will be just about mandatory and the combination will be better than most anything else on the aftermarket. . . since this is a Dundon thread, I am certain most will not mind my bias.
Avera
P.S. As for the 'only loud when I was 4-5K RPM' part, well, I took care of that with valve shaft collars. Eliminated the abrupt transition from quiet to screaming when the valves fly open.
Last edited by Avera; 01-07-2023 at 06:44 PM.
#37
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I have to agree with you 95% . . . Dundon header/OAsP with OEM rear box is almost the perfect setup.
Louder than anything I have heard that is not straight-piped.
Delivers more TQ/HP gains than any aftermarket tune available.
OEM rear box manages drone/resonance impeccably with decent tone.
I threw on the JCR Race Pipe to get that straight-piped decibel level and RSR tone. I got both in spades . . . along with the most unbearable drone/resonance imaginable. I crossed the line and the OEM rear box is back in its place.
So, as to the 5% . . . I have been holding out hope Dundon could deliver the rear box solution myself and many other Dundon header/OAP owners have been hoping would become available. Unfortunately, @Ted@dundonmotorsports sounds less than optimistic Dundon can deliver a small miracle.
Given the RS has the exact same chassis as the GT4, I do not THINK the fact it has a different engine is going to alter the scenario significantly, if at all. If one chooses to go with Dundon headers/OAPs, the OEM rear box will be just about mandatory and the combination will be better than most anything else on the aftermarket. . . since this is a Dundon thread, I am certain most will not mind my bias.
Avera
P.S. As for the 'only loud when I was 4-5K RPM' part, well, I took care of that with valve shaft collars. Eliminated the abrupt transition from quiet to screaming when the valves fly open.
Louder than anything I have heard that is not straight-piped.
Delivers more TQ/HP gains than any aftermarket tune available.
OEM rear box manages drone/resonance impeccably with decent tone.
I threw on the JCR Race Pipe to get that straight-piped decibel level and RSR tone. I got both in spades . . . along with the most unbearable drone/resonance imaginable. I crossed the line and the OEM rear box is back in its place.
So, as to the 5% . . . I have been holding out hope Dundon could deliver the rear box solution myself and many other Dundon header/OAP owners have been hoping would become available. Unfortunately, @Ted@dundonmotorsports sounds less than optimistic Dundon can deliver a small miracle.
Given the RS has the exact same chassis as the GT4, I do not THINK the fact it has a different engine is going to alter the scenario significantly, if at all. If one chooses to go with Dundon headers/OAPs, the OEM rear box will be just about mandatory and the combination will be better than most anything else on the aftermarket. . . since this is a Dundon thread, I am certain most will not mind my bias.
Avera
P.S. As for the 'only loud when I was 4-5K RPM' part, well, I took care of that with valve shaft collars. Eliminated the abrupt transition from quiet to screaming when the valves fly open.
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Avera (01-08-2023)
#38
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There's one available for the GT4 which could potentially be adapted to a 4RS...but there's so little info on it and the cost is pretty high.
Might as well do a proper set of dampers/springs (KW, Ohlins, MCS, etc) with some minor suspension and call it a day.
#40
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You already know what we want . . . what nobody else has been able to produce ![burnout](https://rennlist.com/forums/graemlins/burnout.gif)
A rear box solution to go with your headers/OAPs that has that RSR tone and a few more decibels to boot . . . without unbearable drone.
Yes, we know you have the RS, but us GT4/Spyder owners with your headers/OAPs have been PATIENTLY waiting on your obtaining the RS to get our rear box solution.
Can you deliver . . . next week?
Avera
![burnout](https://rennlist.com/forums/graemlins/burnout.gif)
A rear box solution to go with your headers/OAPs that has that RSR tone and a few more decibels to boot . . . without unbearable drone.
Yes, we know you have the RS, but us GT4/Spyder owners with your headers/OAPs have been PATIENTLY waiting on your obtaining the RS to get our rear box solution.
Can you deliver . . . next week?
Avera
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Avera (01-09-2023),
MechEngr1287 (01-10-2023)
#41
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Last edited by Ksdaoski; 01-10-2023 at 02:09 PM.
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Jevi Javi (01-11-2023)
#42
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Last edited by Ksdaoski; 01-10-2023 at 03:21 PM.
#43
Rennlist Member
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One thought occurs to me about the exhaust... if you develop the RS exhaust system to require the use of the Dundon back box then I see no reason why the existing design you have for the GT4 back box can't be made to work with the new header/OAP design you cook up for the RS. The only reason I see that Porsche changed the geometry of the muffler connection was to manage the longer secondary cat + OPF. Knowing you'll likely come up with a much more compact - cat only - solution you could relocate the connection back to where it is on the GT4. Regardless... I'm still looking forward to seeing what you do with the GT4rs!
Thanks also for sharing that quick tear down
Thanks also for sharing that quick tear down
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
Thanks for posting these!
https://www.instagram.com/reel/CnN4J...d=Yzg5MTU1MDY=
https://www.instagram.com/reel/CnN4J...d=Yzg5MTU1MDY=
#44
Burning Brakes
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You and I have communicated privately and it is no secret we are both among several who have been holding out for a rear box solution that seems more and more to be asking for a miracle.
If I were to guess, we will find out - despite their best attempts - Dundon will never come out with a rear box solution for either the GT4 or RS that matches up well with their headers/OAPs. Dundon will come out with headers/OAPs for the RS that - coupled with the OEM rear box - will satisfy the majority.
'Majority' is an awkward term in this case because RS owner already live in rarified air. Not sure how much aftermarket exhaust business is out there for a lot of competing companies trying to get a piece of the extremely small pie.
Avera
#45
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Great tear down video. Thanks Dunedon. I’m looking forward to seeing what parts you suggest for upgrading my gt4RS.