Alan C.

I just received a call from the installer. He took the car out for a drive and said the headers were worth every cent. Great sound and pull throughout the range and no drone. Said the sound on cold start will bring a smile to your face.

I'm picking it up tomorrow around noon. I'll post my thoughts later in the day.

Jamie@dundonmotorsports

Hi Rick,

Wasn't saying no, please don't take it the wrong way...

Was saying that we've been challenged by everyone and it does get exhausting trying to not get defensive.

I appreciate you putting your money where your skepticism is, you're rare in this industry, most push for a crazy discount or free...

We're excited for you to test them. It will be a little while before we can ship as we have to finish the catted system and get the 2nd batch built. We truly are a small shop, 5 guys, and 3 do service, It's Charles doing development and initial fabrication and Solomon doing the production welding along with Charles, with Charles and I doing the tuning. (you can see Charles is a pretty busy dude, hence your stuck with me on the forum).

We have you down for a set from the next batch and look forward to your feedback.

I'll be making a call shortly, even though it's a bit late in NY.

Sorry if the post came out strong, it wasn't intended directly at you or DeMan Motorsports, but the nature of this industry with so many making claims that have never been backed up, and us posting everything and folks still assuming we're like everyone else is a bit frustrating...

CarAholic

Dying to get a pair of these

Jamie@dundonmotorsports

Left you a phone message at the shop. Give me a call when you get a chance... 3oh2 521 23oh7

stout

It certainly is not a perfect test, for a variety of reasons. However, with the gains claimed, it should be pretty obvious. A GT4 with Dundon headers should walk away from a stock GT4 pretty smartly.

In my experience, there are quite a few variables with dyno tests, as well. One editor I know tried to do the end-all, be-all exhaust test for a magazine and it turned out to be a nightmare due to heat sink, pressure changes during the day, etc. etc. In the end, the power differences were pretty small, the results were contested due to time of day (for instance), and a lot of tuners were unhappy.

The nice thing about a long enough closed-track straightaway—or a drag strip—is that the two cars share the same pavement, air, fuel (if you plan ahead), etc. And there are ways to deal with driver error.

Not illegal at Thunderhill, Road America, Big Willow, etc. Not particularly dangerous, either. Again there are ways to minimize or effectively eliminate driver error. Even the simplest data acquisition would be just one of those ways.

I'll offer up my perfectly stock GT4 for a rolling test or a dyno test, but I am less enthusiastic about letting someone dump the clutch in my GT4. As in...no way.

A very wise engine builder once told me: "Son, I can make a dyno say whatever I want it to." As you note, many companies do use dynos as marketing tools, which has decreased the credibility of dyno results—especially dyno results published by a vendor. That's not your fault, but it is your problem. It's the same problem every tuner faces. The good news: You've generated a lot of interest (which is good for your endeavors...just look at the page views here) along with some healthy skepticism (which is both a challenge to and an opportunity for your company). But there is going to be plenty of interest and skepticism in this crowd when a new product based on a conventional component comes along offering what look to be truly incredible gains.

No one is asking you to republish more data or charts, or trying to exhaust you (nice choice of verb, btw! ). Or at least, I am not—and I do appreciate your explanation of the basic concepts behind your product. Thing is, any intelligent person has no choice but to view all of your data and info as inherently biased—just as they would with Porsche, Chevron, Comcast, etc. They'll listen and think about the information you preset, but it has a different value than a third-party's take (which can also be flawed for various reasons). Having both viewpoints is a lot better than having one of them.

I get you, but sure they do. They go out and collect lap times, 0-60 times, 1/4-mile times, etc. Yes, the dyno is a useful tool. But real-world, in-car testing is critical, too. Your competitors have used it, and I have found some of their videos to be interesting and fairly compelling—even as I took into account the source as well as driver-induced variables.

No worries, man! No one here is out to get you. Actually, a lot of us want to see you succeed. For real. I'm among them—so long as you tell me you're not selling cat-less headers to customers who have posted their intention to run them on the street. If you are, then we have a fundamental difference...but that doesn't mean I wouldn't like to say hello in the paddock.

Thing here is, you've kind of fixed a target on your back by claiming 438.8 hp from a set of headers when it took Porsche AG a new set of heads, new cams, a new intake plenum, a new exhaust system, and a tune to get from 400 hp to 430 hp on the same engine in a 991S. If you've done it, you will gain tremendous respect from a lot of upstanding people in this community—especially if those gains can be repeated or neared with catalysts in place. But you have to understand that the Porsche community is just that, a community. We care about our own, and don't like to see friends get taken for thousands of dollars. Years ago, I conducted a dyno test that showed an intake claiming 30~hp gains actually lost power. It was a bitter pill to swallow for the tuner, but it did right by its customers who had shelled out for the product—and today is one of the more respected U.S. tuners. I also put a twin-turbo 986S claiming "GT2 levels of power" on the dyno, and man was that a long day to find it made about as much power as a 996-2 Carrera—after several hours of tweaking and shimming the waste gates. It sure was a pretty kit, though, and one with some very innovative ideas.

I've found this community is tight knit yet has a very open mind, and open ears too. Again, we want to see you succeed, and bring something cool to the party. You've already got two respected colleagues offering a hand to you, and I take their offers as offers in good faith. If I was a little further along, or was still at Excellence or Panorama, I would look at setting up a three- or four-way comparison test. Not sure which way I would go with that test—there is a "non-Porsche" dyno I like to use—but it would probably include both a dyno test and a rolling acceleration test. It would not be inexpensive to do it right, or even "right." Fortunately, I'm far from the only media game in town...

Rick DeMan

Open invitation to anybody who has ordered a set of these headers.

We will dyno before install, install headers and re-dyno test after with printed results for FREE!

We are in the NY metro area. Feel free to call me directly to arrange.

Thanks in advance!!

AfricanHunter

well. They did start the last WW =)

AfricanHunter

I am in San Diego. Have no affiliation besides buying the DMS headers. Would be open to doing a back to back test at a local dyno with any other comparanble products. Both before tune applied and after.

O5C4R

As a manufacturer I can totally agree and sympathize with Dundon, the amount of unpaid work and stress running your own business producing products that are quite literally an extension of you is extremely under appreciated and wanting to protect you IP is smart.
I am also very happy to have received mine 😀 Probably the only set of these unicorns in the Southern Hemisphere lol.
Gotta say I wish my welders could tig weld like yours👍
Hopefully I'll have these on before xmas 😝

okie981

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?

d00d

Like O5C4R, my sympathies go out to DMS.
The questioning with implication that there must be something nefarious going on with their dynamometer tests, call for the burden of enforcing after sale track only use, etcetera, must be fatiguing.
Please visit other model forum threads for end user tests that have verified those of DMS.
Just because a business makes itself available in a forum doesn’t give carte blanche for every inane question under the Sun, and don’t expect a free header design education.
Many of the questions asked here have already been answered elsewhere or even in this thread, do your homework.
Please let DMS develop their products and get them out the door to those of us who appreciate their hard work.

Spyerx

I can't keep my mouth shut any longer.

^Sorry bud if you are a vendor and make claims and are selling a product based on those claims, those claims absolutely are subject to critique and evaluation. When you buy headers you get or expect: looks good, sounds good, reliability, some performance gains.

Would you praise Johnson and Johnson for the "hard work" of developing a drug that does nothing (for anyone)? And was never trialed and was never peer reviewed?

And let's face it, header design is not a black art. It's well understood.

Those claims need to stand up to critique, peer review, and in the world of cars... the peanut gallery.

Offer:
Anyone that has purchased these headers in SoCal I will be happy to organize a free evaluation of the pre and post performance gains. We can use my aim and some 3rd gear pulls, we can use the shop dyno, etc. I'll foot the bill. I am sure there are some gains. Color me skeptical they are anywhere near what's posted.

OlsenMotorsports

Rick, I have a car here that has a set supposedly ordered, although we have waited over three months for them, which is incredibly frustrating.

I can run the car to the dyno to get a baseline on the BGB tune, swap headers and back to back it.

If they are as good as advertised I could probably sell five sets immediately. But with three months lead time I cant do that no matter what the margins are. In this business excessive down time or waiting time on parts is a deal breaker for me no matter how good the product is. Cars sitting in the shop means money isn't being collected.

Take this with a grain of salt as constructive criticism, but it is just my .02. Cannot sell product we can't get.

-T.O.

d00d

Spyerx, I know you're active on the GT3 forum, did you find DMS cooking the books in any way when they developed those headers?
If not, why would you assume they are now doing so?

mooty

yes, waiting time is not good
espeialy for those who keeps cars 3 week at a time
that's why i have so many **** to sell.
usually i would have sold the car 6 months before stuff i ordred show up.