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We've been getting a ton of questions lately on a recently posted thread using our headers as a baseline for a competitive product. While this is very flattering to be used as the benchmark it seems the data reported was different than data we've generated, so to recap...
All of the below testing was done on a 991.2 GT3 4.0L Manual, in rolling road mode, on our own Dynapack dyno ensuring good airflow to the intakes using fans.
Dundon Valved Side Deletes and Black Lifetime Muffler
25lbft gain at the wheels and about 10whp
Dundon Valved Side Deletes and Loud Muffler (keeping OEM catted headers on the car) compared with Stock 991.2 GT3 4.0L
We've been selling quite a few Street Header and Black Lifetime mufflers to customers looking for great power, less weight, bullet proof reliability and a lifetime warranty (oh and it sound's fantastic as well...).
And for those that are interested...
Dundon Race Headers
47+ lbft gains max and 16lbft gains peak, gains everywhere, and 25whp at 8400rpm
Dundon Race Headers and OEM Muffler compared to 991.2 GT3 4.0L Stock
We have the Race headers installed on a handful of cars around the world and our standard bungs used on the 991.1 GT3/RS are working for the most part (seems the car can adapt with some miles driven). There are intermittent CEL on some cars, so we have been promoting and pushing the Street headers as the difference in power is really quite slight, and keeping cats on a street car really does give you the best of all worlds. That said those that want Race headers, and don't mind a possible intermittent CEL, and having to change the steel/Ti muffler to one that won't crack (like our lifetime center muffler), they're available and have great proven power...
Have the race headers and black lifetime muffler on my .1 RS resurrected from PT3_RS and man are they incredible. Have had limited driving due to crappy weather and cannot wait to drive the car at Spring Smokies. While hp and torque are all good things (right, who would turn that down) what I really wanted was loud and mean. Check. Car seems to spool up quicker, but that is probably me getting use to it. More feedback for you at Smokies.
Well, at least they said you were highly regarded and proven, that exactly what you guys have, tested and PROVEN vs prototype..... Can't wait to get my setup from you guys!!
We've been getting a ton of questions lately on a recently posted thread using our headers as a baseline for a competitive product. While this is very flattering to be used as the benchmark it seems the data reported was different than data we've generated, so to recap...
Do please feel free to comment on our thread, Jamie. I welcome any proper explaination as to why you deem our results to be innacurate.
Also to note our testing was completed on our 991.1 RS, everything you’ve posted in here is Gen2?
Do you have any dynos of the orange quiet muffler with the side deletes for those of us that track on dB limited tracks?
It would also help explain where the 10whp is coming from (muffler or side deletes). I have done side deletes to loose weight but it's always been assumed they wouldn't help peak hp. And most center deletes don't claim much gains but you guys are getting decent gains with just deletes and a muffler. What did the Street headers do with the Black muffler for peak gains?
Last edited by trompazo; 01-31-2019 at 08:22 PM.
Reason: typo
Do please feel free to comment on our thread, Jamie. I welcome any proper explaination as to why you deem our results to be innacurate.
Also to note our testing was completed on our 991.1 RS, everything you’ve posted in here is Gen2?
JC
As a courtesy, didn't want to clutter your thread with banter unrelated to your post...
Thought you were posting 991.2 RS data, as the torque values stock were 325wtq, way higher than the values we get on all the baselines we've run on our dyno. 325wtq is more like a 991.2 GT3 (which is what I posted). Seems a more favorable SAE adjustment is being used with the facility that did your dyno's? Not sure and honestly doesn't really matter if only deltas are used.
Here you go...
991.1 RS Dundon Race Headers, 65F intake Temps, 40whp gains, at the rev limiter
Do you have any dynos of the orange quiet muffler with the side deletes for those of us that track on dB limited tracks?
It would also help explain where the 10whp is coming from (muffler or side deletes). I have done side deletes to loose weight but it's always been assumed they wouldn't help peak hp. And most center deletes don't claim much gains but you guys are getting decent gains with just deletes and a muffler. What did the Street headers do with the Black muffler for peak gains?
Great questions.
We don't sell the side deletes or black/orange muffler as HP/TQ gaining mods, but there is a little bit of benefit. The stock system necks the major flow path down to 2.5" before it goes into the OEM muffler. On our side deletes/muffler packages we can keep the size at 3" with our 3" valves (same as used on our header systems), this keeps the flow unimpeded at lower RPM (where flow restriction and reduction in back pressure can help) and at high rpm when exhaust gasses may start to "bunch up" and prevent gasses from escaping as quickly as possible from the Muffler. There are a few other tricks in the muffler (full xpipe etc...) that help a bit as well.
The Orange muffler uses the same 3" lower flow path, but with added features to reduce the dB, so it's a little heavier, and doesn't flow quite as much.
Feel free to shoot me an email with any other questions. And remember all of our exhaust parts have a 30 day try and love it or send it back for a full refund. If you want to try it and see what you think there's no risk...
As a courtesy, didn't want to clutter your thread with banter unrelated to your post...
Thought you were posting 991.2 RS data, as the torque values stock were 325wtq, way higher than the values we get on all the baselines we've run on our dyno. 325wtq is more like a 991.2 GT3 (which is what I posted). Seems a more favorable SAE adjustment is being used with the facility that did your dyno's? Not sure and honestly doesn't really matter if only deltas are used.
Here you go...
991.1 RS Dundon Race Headers, 65F intake Temps, 40whp gains, at the rev limiter
Ah, would explain. I did think the same when we baselined the OEM car however we’re only interested in the delta and only refer to delta in our test. Could be fuel, AIT’s and correction as you say but importantly everything was totally consistent between the runs as to produce accurate delta readings.
As I’ve openly said, we chose the Dundon Race headers as a benchmark because you guys have done a great job with them. They work and everyone knows they work. Competition is competition but there is zero animosity from our side, only respect for what you guys do.
Ah, would explain. I did think the same when we baselined the OEM car however we’re only interested in the delta and only refer to delta in our test. Could be fuel, AIT’s and correction as you say but importantly everything was totally consistent between the runs as to produce accurate delta readings.
As I’ve openly said, we chose the Dundon Race headers as a benchmark because you guys have done a great job with them. They work and everyone knows they work. Competition is competition but there is zero animosity from our side, only respect for what you guys do.
JC
All good brotha, just wanted to clarify data that wasn't jiving with ours and others that have dyno'd our setup...
01-31-2019, 07:21 PM
Dundon Header 991.2 GT3 Dyno Comparisons
