COBB Tuning

ATP release for POR11 and POR12 is still looking good for release end of this month/early February. Couple more clean up items and some testing to complete then off to marketing to release it goes.

Thanks!

~~~~Jared

Ttz06vette

Which version of PT works with the Turbo S(2017) 991.2 again??

flickroll

PTS-BRG

TXGold: Got the Dragy last night, plan on doing some testing today and posting later on today.
I don't know much about how it works but, I guess I will figure it out. I plan on launch starting it from 0 and going 1/2 mile.
I assume that the Dragy will break down the 0-60, 60-100, 1/4 mile and 1/2 mile from that..

cosmo1

I am also considering Vektor Headers and Kline's but don't see where the $1000 price difference is coming from between the two types...

PTS-BRG

^^^^ Neither does anyone else except 4 Point 0..

This has been an issue for many months now. We all would like to understand and all we get told by Vektor how everything is CNC machined with much prettier welds.
I tried to get a set to test against Kline but was denied so, I went with Kline for the exact reason you stated.. what justifies a 50% premium of one over the other?
Then, when I saw that the Vektor's actually hung lower than the rear crossbar I got worried about clearance. The Klines are tucked up higher than the crossbar, so I went with Kline.

Now Flickroll recently posted he is going to get a set and was given the ability to do a before and after dyno test which, in theory sounds great. But, who is doing the testing?
If its Vektor, with Vektor employees on a Vektor provided Dyno, then I wouldn't put much weight in the results. Flickroll is 100% honest and one of the best guys on RL, so I hope he goes independent.

In the end, even if the Vektor's provide gains, the question would still remain how those gains compare against Kline, Fabspeed, Cargraphic, or any other Header manufacturer..

cosmo1

I actually spoke with Hydra Motor Works who tuned my car and they said they had experience with Kline and not Vektor. When I spoke with a Vektor rep yesterday he told me the difference in price was the due to using the better SS.. I definatley don't want anything hanging any lower on my car than the lowest point now.. To me the Vektor looks better but 1k more seems wasteful..

PTS-BRG

I am not a metallurgist so, I cannot tell you what the benefits of superior SS are (if that's even true) over a lower grade of SS on an exhaust pipe. Being that SS is cheap to begin with, I dont think the difference would be $1000 in the raw material. Once they are coated I would also assume the heat characteristics would be similar as the coatings retain the heat more than the metal does.

I have always said it was smoke and mirrors and some fancy Social Media hype to justify the crazy price. I was further convinced when they wouldnt offer me a refund of a full retail purchase (no discount requested) if the pipes didn't perform CLOSE to what they advertised. If the manufacturer wouldn't stand behind their performance claims with a refund then I was in no way going to be that fool to blindly follow an online chart without proof.

I even agreed to pay John at BGB Motorsports to do the testing, who everyone knows is a stand up guy with long history of racing heritage and experience. The answer was still NO. No dyno trickeration with John.

Add to that the lack of any history with Porsche, throw in the poor lower hanging design (PS Kline and Vektor both use equal length pipes)..and I think you can understand how I arrived at my decision.

The day an honest, credible dyno comparison is made between the two showing one is better than the other with regards to performance, is the day I would consider jumping ship. Until then, I am a Kline fan.

PS: My Dragy performance tests will be up later today so you will have some idea how my car performs with a Cobb Tune and Kline parts if that helps..

cosmo1

Once again I appreciate your honest review and based on that I'm going with Kline. I will also try to get some tests in today hopefully we can compare.. TGIF everyone!!

spdracerut

well, I guess it comes down to your priorities. I have no doubt the Vektor headers make the best power based on two points of reference: their design compared to the others (largest radius bends, a merge with all runners entering around a central point instead of a flat merge) and also comparing gains between the three makes with available (not back to back, but best available and calculated % change) data. I crunched the numbers already and my analysis is out there. The other aspect is reliability of the product. 321 has higher strength at temperature compared to 304. So of you beat on your car a lot, this is of value. The Vektor design has much fewer welds compared to the kline design and every weld joint is an additional weak/potential crack point due to the Heat Affected Zone (HAZ) creating brittle material. Material costs are a big factor of course, just look at the cost of kline headers in inconel. So, from my point of view, if power and reliability are you priorities (drive hard a lot, track car, etc), then Vektor is the best option. If your car is more of a cruiser and the sound is more important than performance, the kline is a better option to save some money. But in the grand scheme of things, say you have a gts that cost you $140k, I would consider the extra cost of the Vektor headers as very little for the benefits. Another cost reference, look at his much all the various options on the 911 are and consider headers make an actual quantifiable improvement in both response and power. Sound is subjective of course. As for hanging low, the only real risk scenario I can see is if your backing the car up against a curb or parking stop. Please excuse any typos, typing from phone at airport.

PTS-BRG

SPD: You know I value and respect your knowledge regarding chart reading but, in this case your comments aren't accurate or fair IMO.

Yes, you saw data logs on three cars with three different downpipes. You failed to mention that all three cars were different 911's.
My car in particular, is a Targa which is 325lbs heavier than the other two. As you also pointed out, my car has a higher drag coefficient so, it loses 8-9% power based on those factors alone. Your data only shows speed at rpm. So, the actual power produced isn't really known. Only that the lighter car with lower drag coefficient is faster at "6700" rpms. Well, I dont need a handheld Cobb AP to tell me that, with all things being equal..


4 point 0's car is built for one purpose..speed racing. He has a much lighter coupe, several other mods, Titanium exhaust, etc,, If his car had the EXACT same mods as mine his car would still be faster.


As far as the design, that is pure speculation on your part. Stronger welds and less welds means nothing when it comes to performance. More fail points? Ok maybe, but they would be replaced by Kline if they failed and as far as I know and have read, I have never seen a single Kline header report a broken or failed weld in all my years of research and online Google searches..

With Regard to the "largest radius bends, a merge with all runners entering around a central point instead of a flat merge" sounds good. Reads well. Looks nice. But, until it's proven to be more powerful its just fluff.

I have seen all of the scientific charts showing how the larger bends and pipe diameter allows for more air flow, less turbulence, etc. Again, if the headers are providing MORE air flow than the car can use than IF Vektor is providing even more air flow than the Kline, what difference does it make? If the car cannot use any more air than X, what difference does it make if the Vektors make 4 times X? The car can only flow so much..

The only analogy I can make is a garden hose. I have a 1" hose connected to my faucet. I turn it on full blast and it flows 4 gallons a minute. Ok, Now I connect a 5" diameter hose to the same faucet. Will it now flow 20 gallons a minute? There is a limit, a bottleneck a design maximum that the faucet can flow with NO Hose. So, increasing the hose diameter only helps when the hose limits the flow to begin with. Once the max flow has been reached, a larger diameter hose does nothing more... Silly analogy but, hope it helps someone understand the concept.

spdracerut

I did make plots showing percent power gain at different rpm points from dyno data which I posted on that other forum. And like I said, not perfect comparison as one car was a S and another a GTS. Both Cobb stage 1 tunes, but the gts had high flow cats. And of course the gts has bigger turbos. But it was the best available data as the time. Plane doors closing!

fsmich

Add me to the list of Vektor...fans (now plural).
I don't have a tune, started with X51 kit and Akra cats,then Akra muffler, and finally Vektor headers. The Vektor headers have been the most noticeable seat of the pants improvement. Full boost comes on much quicker now.

Aatish

I'll partake in 60 rolls with anybody once I get my tune. Stock headers for now; cat bypasses and my in work wing mod for increased inter cooler air flow...

///M3THOD

Can you elaborate on this? Is it just a lip on the spoiler assembly face to direct more airflow into the IC's?