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30-40+ whp due to air filter restriction seems pretty hard to believe...
yep the quoted Dundon BHP claim 10 pages back is starting to look a bit daft !
so far with have a 12 bhp real gain atm ! which is about right getting 2 cats out the system
the rest is done by software alone as a standard car just with a tune gives 405BHP ! (crank)
and as I said above the TB and IPD helps the mid range and offers no real peak BHP.
also new paper filters have been tested to flow just as much air as K&N/BMC the issue is the paper ones clog up faster from day 1 of use, where the K&N/BMC keep flowing for longer.
new a new paper filter vs a K&N I would say is the same.
Its because the testing was done without the K&N high flow airfilters that we've been using since day 1.
Our testing was done with the BMC Filters installed, not the K&N.
Do the K&N flow that much better then the BMC to make the 20 additional HP we are looking for?
The headers are nice pieces, the sound is awesome. And your tune is well done. It pulls smoothly, and drive-ability is very nice. Horespower gains with the headers are right on par with what you expect with a header swap. It is a well done piece.
Its because the testing was done without the K&N high flow airfilters that we've been using since day 1.
i'll post up some testing we did in the last few days to try and duplicate these results and show what's missing... We have and can show the differences between what was shown by others and what people are feeling.
No deception no smoke and mirrors just data... the context of the data is key and deciphering it all is even more key.
We've been transparent and will continue to be.
No place on your Day 1 posting do you mention, refer to or include the K&N filter as a VERY important part of the setup. We will try to bring the test car back and run with the K&N filters to bring this test to a finish.
Originally Posted by Jamie@dundonmotorsports
Hi All,
We're very happy and humbled by the response we've received from the forum members on our development work for the GT4 so far. We've finished up the development and production prototypes. Just tested them on the car this morning.
Here's the results on a stock car, bolt on, no tune.
Our dyno read the stock car at 330.8 whp at 7400, Porsche rates the car at 385bhp at 7400, this is 14.1% loss with our Dynapack 4000 hub dyno running the car in Rolling Road mode using the factory PIWIS tools.
Using this Conversion the headers alone get us to
426BHP
For those that want a bit more we offer a Cobb Accessport with a Dundon Motorsports Pro Tune tailored to the Race Headers.
Dundon GT4 Race Headers with Dundon Pro Tune
Dundon GT4 Race Headers, Dundon Pro Tune. 377.1 WHP
The Headers are 18 Ga 321SS. We keep stressing this as the quality of the materials matters. It dictates fitment, it dictates the quality of the welds and the ability of the system to withstand the abuse a car like the GT4 can dish out. This makes our systems cost more than our competitors as 321 is typically 2x the cost of 304SS (what most others stainless systems are made with), but it's important to us to use great materials. We believe in it so much that we offer a lifetime structural warranty to the original owner of our systems.
Design:
The design of our headers is unlike any other on the market, and was specifically created for the GT4, not just to fit a 981 Cayman, but specifically for the 3.8L engine in the GT4. When we make headers for the rest of the Cayman family they will specifically designed for them as well, each engine requires a different design to extract the most from it!
Fitment with factory PSE:
The Dundon Race headers are designed as a direct replacement to the factory system and will bolt right up to the factory sport exhaust, so you retain your valves and ability to quiet the car down for "dinner date duty".
Sound:
Very much a dual personality system. With your foot out of the throttle very livable, talk on the phone in the car etc. PSE button on and foot in it, and get this!
To keep the CEL off while using this racing and offroad use exhaust, we have improved our post cat O2 bung defouler so that it is off 99% of the time. We've been testing with 991 GT3RS with very finicky programming and it's been working like a charm.
Plenum/TB:
We ran a popular plenum and 82mm TB on our headers and our tune and found no measurable improvements even at high rpm. This is good news to some as it means the power improvements are easily achieved with just headers and a tune or even headers alone. We do believe there is more power available through work on the intake/plenum and we will be pursuing this as a Stage 3 package. Work is on going fitting porsche factory parts as a modification.
Street System:
Catted system development is already underway and we will putting together a prototype for testing in the next 2-3 weeks. We need to finish the 991 GT3 catted system first and then back to the GT4 catted.
Dundon Race Header Pricing and ETA:
We sold out the initial group buy and as we finish the first batch of 20pcs, we're already getting materials in stock for the 2nd batch of 20. We're looking at 6-8 weeks to have the next 20 finished. We'll push to do it faster, but this is realistic looking at the last 20 pcs.
Retail Pricing for them is $4250.00 Rennlist Pricing is $3950.00
Ground shipping in the US is free
Tune Pricing:
The Cobb Accessport is a very convenient and stable method for tuning a modern vehicle. It has the ability to store tuned and stock files, log engine parameters and read/clear engine fault codes. The price of the Cobb Accessport is for the device and some generic off the shelf tunes. The OTS tunes add some power, but not near as much as our custom developed Pro Tune.
Cobb Acessport: $1295
Dundon Pro Tune for Race Headers: $495
Package Pricing:
We'll offer a further discount for those that order the headers, Cobb AP and Dundon Pro Tune at the same time.
Total Package Price: $5590 (savings of $250)
Please email Jamie@dundonmotorsports dot com and we will send a paypal invoice for a deposit
As always, any and all questions are welcome!
__________________
2016 GT4-R
Rick DeMan
DeMan Motorsport
Upper Nyack, NY
845 727 3070
Porsche Sales & Service
Porsche Race services and parts www.DeManMotorsport.com
Am I missing something or are these numbers nowhere close to what dundon originally showed? Not trying to be negative but kind of have to talk about the emperor's clothes here. Looking back at the original dyno claims and looking here, I'm not even sure there is a truly desirable change from stock.. yes you get the torque bump in the midrange as with the other brands, but there is some significant dipping below the stock line as well which if I recall was not present with cargrafix or fabspeed. And the power claims are simply not there. What am I missing?
Have been following the thread closely and it has gotten interesting, both from the claimed performance gains perspective as well as the recent dyno graphs perspective.
Dundon has been pretty transparent thus far, so perhaps it is more a complete package with filters, headers, tune, etc tested in a particular way that got them those results as opposed to just the header swap getting all the gains.
Looking forward to someone also posting a roll race with these mods and a stock GT4.
ipd and TB gives NO peak gain but is better on the torque curve so worth while.
All the curves I have seen show an increase in peak power and mostly at the top end. My comment is how much is due to the filter and how much the ipd/tb
Here's the results from MQANDIL's car that we just installed on Wednesday
Stock vs Headers no air filter, stock DME Headers only no filters, GT4, 6300 rpm about 10whp
Headers only no filters GT4 7300 rpm about 35whp
Headers only no filters GT4 3600 about 37lbft gains
Headers and Airfilters Headers and Filters 6300 about 20whp gains
Headers and Filters 7300 about 40whp gains
Headers and Filters 3600 about 48lbft
There are still some differences we're seeing between the Cobb AP stage 0 tune and the Stock DME. The Stage 0 tune is what we've been using as "Stock" for our tests as we loaded the it on our car long ago. And is the stock tune to use from Cobb. We'll continue to investigate this. Also MQANDIL is coming back to see if adaptations after some miles makes a significant difference.
You can see we're up in some areas and down a bit in others.
I hope all can see that we are trying to be as transparent as possible even though this opens us up.
Our 100% moneyback guarantee stands and we will take back any system that the customer isn't pleased with. So far all are pleased, even the customers that have been tested elsewhere.
In the end we want happy customers, not to win the internet...
You won't hear any more from us until after the New Year, everyone go enjoy your friends and family and have a safe and happy holiday.
Let's compare max to max gains.
I see ~349HP on the stock (max HP)
And I see ~364HP max on the other setups.
That's a 15WHP gain (MAX).
We all get the gains UNDER the curve, those are great, especially the dips top and mid end.
But let's be real here, no parts maker quotes the max point in time gains, they all post the gains they see at max HP or TQ. Sure, area under curve is super critical. But when you quote those big numbers you're not quoting at apples to apples.
12-23-2016, 07:00 AM
