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Hi everyone. Here is a teaser about our new High Flow Cats that are in dev..
All have Vektor Headers. All runs shown are second pull (out of 3). Coarse Dashed Line was before blower setup was added; plots stopped at 6,700 RPMs, with blowers 7,000 RPMs.
Coarse Dashes are Cobb Stage 1 w/OEM Cats
Fine Dahses are Cobb Stage 1 Vektor HF Cats
Solid Line Stage Cobb 2 Vektor HF Cats
We are in the process of obtaining independent testing.
Check ourweb page for more information about our company.
New HF Cat feeler....
Last edited by VektorPerformance; 03-31-2021 at 05:45 PM.
Looking forward to seeing how these turn out and thanks for providing data with your product, I never see that as a bad thing. Good to see a VA based performance shop too, when I had an Evo I went to PA for my tune because there were not any good shops in VA at the time.
Looking forward to seeing how these turn out and thanks for providing data with your product, I never see that as a bad thing. Good to see a VA based performance shop too, when I had an Evo I went to PA for my tune because there were not any good shops in VA at the time.
If you're ever in the area, feel free to stop by and I'll give you the nickel tour. We have one of the nicer dyno cells on the east coast too
They look great! There is significant opportunity for product differentiation on the HFCs in the quest for maximum power. The gains are all in the details. Off the top of my head, the main design freedom areas on the 991.2 cat for non-PSE are:
The cat core: cell count, diameter, length. The lower the cell count, the larger diameter, the shorter the length, the less the restriction. Of course, with lower cell count and shorter length, there's less emissions scrubbing going on.
Core location, offset or not. If the core is offset from the turbo outlet, the flow won't be as evenly distributed across the core = higher flow losses. So you want the core centered with the outlet.
Conical diffuser from the turbo outlet to the core. Anyone who did Formula SAE in college and had to design the intake restrictor knows the importance of the conical diffuser angle and pressure drop. The rule of thumb for a conical diffuser is to not exceed a 14-degree included angle/7-degrees from the center axis. Basically, you want your diffuser as narrow and long as you can make it to minimize flow separation inside the diffuser as the flow separation increases pressures drop.
The angle of the conical nozzle on the outlet of the cat which narrows down to the 90 degree outlet pipe is not nearly as critical. But what's important is the transition from the cone into the pipe. You want as smooth as a transition as possible to minimize the flow separation at the entrance.
The last major area for opportunity is the sizing of the 90 degree pipe. The bigger, the better and it's really important when it comes to bends. Remember that flow pressure drop is a function of velocity SQUARED. So anything you can do to reduce the velocity (bigger diameter pipe) has an exponential effect in reducing pressure drop. In a straight pipe, looking the basic Moody chart for pipe flow losses, the friction factor is in the 0.01-0.02 range.
For flow in bends, we don't even look at the friction factor because it's so low compared to the loss coefficient due to the bend.The loss coefficient for a 90 degree bend is like 0.2-0.3, or around 20x higher than the friction factor for a straight pipe. So using as big as a diameter pipe for the 90 degree bend as possible pays big dividends in reducing pressure drop.
Regarding materials, the exhaust temperature coming out of the turbo in a typical gasoline application is around 150 degrees Celsius/270 degrees F lower than the exhaust gas going into the turbo (what the header sees). The turbine wheel is extracting power from the exhaust flow, power = heat, so the exhaust flow gets colder as power is extracted out of it. So, the high temp capability of 321SS is not necessary for the cat/downpipe.
I remember reading an article way back when the Ducati 999 was coming out when I was in engineering grad school. The engineering director was walking through the design office and stopped by one engineer's desk where the engineer was designing the brake lever. The engineer had an older generation 996 lever on his desk (I think, this was like 15 years ago). The director asked how much the new 999 lever weighed and the engineer said something like 120 grams.The director asked how much the older lever weighed and it was something like 112grams; I'm making up the numbers a bit, again, 15 years ago... The next day, the new 999 lever weighed like 108grams. That lesson has stuck with me in my engineering career. I've done competitive bench marking and analysis all the time in all my job roles (I've worked in turbos, electric vehicles, and now HVAC) as I have to know how my projects stack up with what's already out there.
Any idea on the diameters for: Fabspeed, Kline, Akrapovic, Soul, AWE? I tried searching all of the internet but no luck.
Soul is also 120 mm, and I have heard that Akrapovis and Kline are 130 mm.
My Soul at 120 mm seems to work okay, and the power increase from sport cats to cat-less is not huge.
Sharpening our pencil on the design in an attempt to bring to market a more competitive bang-for-the buck offering. We're throwing around the idea of making a cast downpipe with a high flow GESi cat. Target price: $1,795.
Appreciate any feedback, questions, or concerns you may have.
09-11-2019, 05:28 PM
Vektor Performance High Flow Cat
