Dundon GT4/Spyder Race Header Group Buy
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Hey all, I want to bring some clarity to the posts from yesterday as it appears there may have been some slight misunderstanding by a few. First, we fully know and expect complete independent testing on our product. We are not expecting anyone to just take our claims because we claimed it. (Even though that seems to often be the expectation by many of our competitors.) We are excited for you all to see first-hand (through independent tests) what we already know to be true. And as some have correctly posted since yesterday, anytime Dundon has made a claim on any of our products it has ALWAYS stood up to independent verification … and this product will be no different … as audacious as our claims may seem to be. Part of the reason for this is our patent pending design of this particular header, which helps maximize volumetric efficiencies.
If any of you sensed frustration in my posts yesterday, or interpreted my words as being resistant to independent testing, that would have been an error on my part. That is not the case at all. Please test at will!
From the beginning we have committed to be a different kind of company. A company that is transparent in our good AND our bad. If something doesn’t work … we admit it publicly and then show the fix. If something is a work in process … we show the tweaks along the way. And when something hits a home run … we eagerly post that as well.
I would challenge everyone on this forum (not just this thread but the entire forum) to request that same level of transparency from every producer of aftermarket parts, whether it be exhausts, plenums, tunes, etc..
I also realize we may be getting more scrutiny because our GT4 race headers appear to claiming the most bolt-on power in the marketplace. We get that. We would likely feel the same way if the shoe was on the other foot. (We’re just glad it’s not. We really like the way this shoe fits. Ha.)
But here’s the good news. As I mentioned yesterday, we have our first 20 sets that have either been recently received by our customers or are in the process of being received. It is these sets that will show this community that we have gone to great lengths to provide highly accurate and detailed data.
These will be the nations test subjects … if the owners allow. They have to be. Why? Because we don’t have any sets left … even for our own car (sigh!) … we ordered parts to build 20 sets and have sold 20. If we had extra sets just sitting around that might be different, but we don’t. So, please be patient. We are a small, start-up company, that is running at full speed to produce the best quality product on the planet, both in terms of performance and quality.
Which does lead to addressing the 3-month timeframe. That bothers us even more than it bothers those of you who have been waiting for these units. We hate it. Unfortunately, however, with these being the first sets built, we ran into unforeseen issues along the way … I’ll spare you the details … but those have been resolved and everyone who has paid for their headers either have received them or will be receiving them very shortly. We do not anticipate that this long delay will continue in the future; however, we do have demand outstripping our current manufacturing capacity for all of our products, as every one of our header sets is hand-made in our own shop … and crafted with the care and attention of a piece of art more so than an automotive part.
I think very soon this community will see, through the independent tests that will certainly ensue, that we have made a unique and special product for the racing and dedicated track community that will not only stand up to our claims but also surpass what many of you seem to believe is possible.
And … important note to Olson Motorsports as well as anyone else who wants to run tests … please take care running anyone else’s tune (other than the stock GT4 tune from the factory) on this car with our headers. Not only will it likely not produce the gains we have claimed but it could put the car at risk… for many different reasons … as we don’t know what is written into that tune in regard to fueling, timing, etc.. Not saying other tuners can't make great tunes, they just haven't made a tune for these headers yet. And while we have created a product that works exceptionally well without an after-market tune, for a customer to receive the most efficient gains from our product they would need to use our specially optimized tune … a tune we have literally spent hundreds of hours going cell by cell in the maps to perfect. So please note, I am publicly saying that for our gains to be confirmed it shoult either be on the stock tune or the Dundon Pro tune. If someone uses a tune other than one of these they could possibly experience poor results or worse, potentially damage the car.
And lastly, while we love participating in this forum and will continue to do so, we need to take a step back for a while … at least in regard to these long posts … as this has taken a disproportionate amount of our time recently. So, all of that to say, if there are periods of silence from us please don’t interpret that as anything other than a crazy-busy production schedule that needs our attention. However, we are truly looking forward to reading the impressions and results of those who are receiving these first 20 sets. We appreciate all of your support. We’re excited for you and the world to experience what we have worked so incredibly hard to produce.
Sincerely,
Jamie and the entire Dundon Team
If any of you sensed frustration in my posts yesterday, or interpreted my words as being resistant to independent testing, that would have been an error on my part. That is not the case at all. Please test at will!
From the beginning we have committed to be a different kind of company. A company that is transparent in our good AND our bad. If something doesn’t work … we admit it publicly and then show the fix. If something is a work in process … we show the tweaks along the way. And when something hits a home run … we eagerly post that as well.
I would challenge everyone on this forum (not just this thread but the entire forum) to request that same level of transparency from every producer of aftermarket parts, whether it be exhausts, plenums, tunes, etc..
I also realize we may be getting more scrutiny because our GT4 race headers appear to claiming the most bolt-on power in the marketplace. We get that. We would likely feel the same way if the shoe was on the other foot. (We’re just glad it’s not. We really like the way this shoe fits. Ha.)
But here’s the good news. As I mentioned yesterday, we have our first 20 sets that have either been recently received by our customers or are in the process of being received. It is these sets that will show this community that we have gone to great lengths to provide highly accurate and detailed data.
These will be the nations test subjects … if the owners allow. They have to be. Why? Because we don’t have any sets left … even for our own car (sigh!) … we ordered parts to build 20 sets and have sold 20. If we had extra sets just sitting around that might be different, but we don’t. So, please be patient. We are a small, start-up company, that is running at full speed to produce the best quality product on the planet, both in terms of performance and quality.
Which does lead to addressing the 3-month timeframe. That bothers us even more than it bothers those of you who have been waiting for these units. We hate it. Unfortunately, however, with these being the first sets built, we ran into unforeseen issues along the way … I’ll spare you the details … but those have been resolved and everyone who has paid for their headers either have received them or will be receiving them very shortly. We do not anticipate that this long delay will continue in the future; however, we do have demand outstripping our current manufacturing capacity for all of our products, as every one of our header sets is hand-made in our own shop … and crafted with the care and attention of a piece of art more so than an automotive part.
I think very soon this community will see, through the independent tests that will certainly ensue, that we have made a unique and special product for the racing and dedicated track community that will not only stand up to our claims but also surpass what many of you seem to believe is possible.
And … important note to Olson Motorsports as well as anyone else who wants to run tests … please take care running anyone else’s tune (other than the stock GT4 tune from the factory) on this car with our headers. Not only will it likely not produce the gains we have claimed but it could put the car at risk… for many different reasons … as we don’t know what is written into that tune in regard to fueling, timing, etc.. Not saying other tuners can't make great tunes, they just haven't made a tune for these headers yet. And while we have created a product that works exceptionally well without an after-market tune, for a customer to receive the most efficient gains from our product they would need to use our specially optimized tune … a tune we have literally spent hundreds of hours going cell by cell in the maps to perfect. So please note, I am publicly saying that for our gains to be confirmed it shoult either be on the stock tune or the Dundon Pro tune. If someone uses a tune other than one of these they could possibly experience poor results or worse, potentially damage the car.
And lastly, while we love participating in this forum and will continue to do so, we need to take a step back for a while … at least in regard to these long posts … as this has taken a disproportionate amount of our time recently. So, all of that to say, if there are periods of silence from us please don’t interpret that as anything other than a crazy-busy production schedule that needs our attention. However, we are truly looking forward to reading the impressions and results of those who are receiving these first 20 sets. We appreciate all of your support. We’re excited for you and the world to experience what we have worked so incredibly hard to produce.
Sincerely,
Jamie and the entire Dundon Team
__________________
Dundon Motorsports
Gig Harbor, WA
253-200-4454
jamie@dundonmotorsports.com
www.dundonmotorsports.com
Facebook.com/dundonmotorsports
Instagram @dundon_motorsports
Dundon Motorsports
Gig Harbor, WA
253-200-4454
jamie@dundonmotorsports.com
www.dundonmotorsports.com
Facebook.com/dundonmotorsports
Instagram @dundon_motorsports
#333
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Jamie, as an engineer I really commend you guys on your open peer review approach here with data supporting your claims. Very impressive work!
Regarding the custom tune and gains, how do you think those would work or be impacted by 91 octane max fuels available in certain states?
the last time I used Cobb on my old STi, they had different tunes for 91 octane max vs 93, etc., though I could see that being more critical for turbo engines.
Would appreciate your feedback on safety of track use with 91 octane with your setup. Thanks!
Regarding the custom tune and gains, how do you think those would work or be impacted by 91 octane max fuels available in certain states?
the last time I used Cobb on my old STi, they had different tunes for 91 octane max vs 93, etc., though I could see that being more critical for turbo engines.
Would appreciate your feedback on safety of track use with 91 octane with your setup. Thanks!
#335
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Jamie, as an engineer I really commend you guys on your open peer review approach here with data supporting your claims. Very impressive work!
Regarding the custom tune and gains, how do you think those would work or be impacted by 91 octane max fuels available in certain states?
the last time I used Cobb on my old STi, they had different tunes for 91 octane max vs 93, etc., though I could see that being more critical for turbo engines.
Would appreciate your feedback on safety of track use with 91 octane with your setup. Thanks!
Regarding the custom tune and gains, how do you think those would work or be impacted by 91 octane max fuels available in certain states?
the last time I used Cobb on my old STi, they had different tunes for 91 octane max vs 93, etc., though I could see that being more critical for turbo engines.
Would appreciate your feedback on safety of track use with 91 octane with your setup. Thanks!
We're using 92 octane with 10% ethanol on our tests. We would decrease timing a tiny bit at the torque peaks, but that's about it. I'd expect the car to be within 3-4whp of our tests.
We haven't touched the knock sensitivity so the car is still very capable of trimming timing as necessary. We run our dyno runs pretty hot, 210F coolant and 230+ oil temps to really ensure the car doesn't fall on it's face in the real world.
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#337
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Let me chime in with my thoughts on the headers. I met with fellow Rennlister TM5 today to take the car out for the first time. TM5 is looking for a set of headers for his GT4 and I think today may have made up his mind.
Cold start - The exhaust has a bit more of a bark but not obnoxious. If you have sensitive neighbors they will appreciate this.
Warm up - We drove around town keeping the revs below 3k while waiting for the oil to get up to temp. During this phase it was easy to carry on a conversation and the interior noise with the windows up was pretty much stock. There was absolutely no drone!
Warmed up - I made a couple of runs at moderate through the lower gears and the car has more pull. Next I made a couple of harder runs up to 5k through 2nd gear. At 4k the sound really comes alive and as the revs hit 5k the car is pulling harder. Next up a couple of runs WOT just into 3rd gear. Completely different car. The pull from 5k is outstanding. Finally I switched on the sport button and you have to love the sound. On the way home I found a clear section of highway with an overpass and was able to make a WOT run up through 2nd gear, a tall 2nd helps, and to me the car sounds better than my 15 GT3. The CEL never came on during today's run.
I couldn't find a dyno facility that could deal with the non rotating front wheels in my area but I trust the Dundon numbers. Matt Moreman did a good job of documenting his Dundon headers on the 991 GT3 list and there were no surprises. I'm sure someone will have second party numbers in the not too distant future.
I was thinking of adding short gears but for now I am completely happy with the car. Probably the next thing I would add would be a Guard diff. I've had good results with their products in the past.
The car is garaged now till spring. Hopefully I'll have the Dundon cats on by then.
If you have a set of these on order you will not be disappointed.
Hopefully TM5 will chime in with his thoughts on todays ride along.
Thank you Charles and Jamie.
Cold start - The exhaust has a bit more of a bark but not obnoxious. If you have sensitive neighbors they will appreciate this.
Warm up - We drove around town keeping the revs below 3k while waiting for the oil to get up to temp. During this phase it was easy to carry on a conversation and the interior noise with the windows up was pretty much stock. There was absolutely no drone!
Warmed up - I made a couple of runs at moderate through the lower gears and the car has more pull. Next I made a couple of harder runs up to 5k through 2nd gear. At 4k the sound really comes alive and as the revs hit 5k the car is pulling harder. Next up a couple of runs WOT just into 3rd gear. Completely different car. The pull from 5k is outstanding. Finally I switched on the sport button and you have to love the sound. On the way home I found a clear section of highway with an overpass and was able to make a WOT run up through 2nd gear, a tall 2nd helps, and to me the car sounds better than my 15 GT3. The CEL never came on during today's run.
I couldn't find a dyno facility that could deal with the non rotating front wheels in my area but I trust the Dundon numbers. Matt Moreman did a good job of documenting his Dundon headers on the 991 GT3 list and there were no surprises. I'm sure someone will have second party numbers in the not too distant future.
I was thinking of adding short gears but for now I am completely happy with the car. Probably the next thing I would add would be a Guard diff. I've had good results with their products in the past.
The car is garaged now till spring. Hopefully I'll have the Dundon cats on by then.
If you have a set of these on order you will not be disappointed.
Hopefully TM5 will chime in with his thoughts on todays ride along.
Thank you Charles and Jamie.
#339
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I'm an engineer as well, although most days I have to wear my sales hat...
We're using 92 octane with 10% ethanol on our tests. We would decrease timing a tiny bit at the torque peaks, but that's about it. I'd expect the car to be within 3-4whp of our tests.
We haven't touched the knock sensitivity so the car is still very capable of trimming timing as necessary. We run our dyno runs pretty hot, 210F coolant and 230+ oil temps to really ensure the car doesn't fall on it's face in the real world.
We're using 92 octane with 10% ethanol on our tests. We would decrease timing a tiny bit at the torque peaks, but that's about it. I'd expect the car to be within 3-4whp of our tests.
We haven't touched the knock sensitivity so the car is still very capable of trimming timing as necessary. We run our dyno runs pretty hot, 210F coolant and 230+ oil temps to really ensure the car doesn't fall on it's face in the real world.
#340
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OP - In earlier posts you describe how your race header depends on the OEM GT4 exhaust to make maximum power because that's what you used to optimize the header design. When you offer your catted system, I'm assuming you will be providing a cat-back design and the OEM system will be removed?
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#343
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d00d, you're right, and I went back and found the answer (below) to my question above in an earlier post on this thread. I missed it as I read through the thread, probably because I was drooling over the photos and test results posted by Jamie.
Congrats Jamie on your innovative header design.
That 4th tube is patent-worthy for sure. Your design reminded me of a 2-stroke motorcycle/kart engine tuner I worked with back in the early '70s, Jim Stroud at MiSI. He designed some un-conventional looking exhaust pipes. They had ~4" dia. flat ends welded on to seal off the end of the ~4" dia. pipe barrel where exhaust would normally exit, then he would cut a rectangular slot (sometimes round hole depending on tuning and engine) on the barrel of the pipe about 3 to 5 inches forward of the flat, closed end of the pipe. With a race-tuned 125 or 250 cc engine at fast idle, the exhaust would sound like someone hitting the bottom of a Folger's coffee can with a ball-peen hammer and not much exhaust note.
The exhaust sound waves were slapping smack into that flat end of the pipe, and gasses would flow out the slot or hole. For a few years he had people from all over the US buying his exhaust stuff for flat track motorcycle and kart racing engines.
Congrats Jamie on your innovative header design.
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#344
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No worries, I posted mainly so Jamie wouldn't feel the need to waste his time responding to something he'd already addressed.
I'll respond in my Vehicle Marketplace listing to keep from taking this thread off topic.
https://rennlist.com/forums/vehicle-...ed-stitch.html
https://rennlist.com/forums/vehicle-...ed-stitch.html
Last edited by okie981; 12-11-2016 at 06:58 PM.
#345
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^Alan thank you for the ride along yesterday to check out the new Dundon headers.
With all of the banter on this thread my expectations were high and must say that I walked away throughly impressed. Surprisingly very oem like until you put your foot down then a strong push and glorious sound from about 3500 to redline that leaves no doubt this mod transform the car. No question - Alan's car would smartly walk away from my stock GT4. Kudos to Dundon for a great product and for finalizing my decision of what to buy myself for Christmas
With all of the banter on this thread my expectations were high and must say that I walked away throughly impressed. Surprisingly very oem like until you put your foot down then a strong push and glorious sound from about 3500 to redline that leaves no doubt this mod transform the car. No question - Alan's car would smartly walk away from my stock GT4. Kudos to Dundon for a great product and for finalizing my decision of what to buy myself for Christmas
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