MazdaSpeed 6 | CorkSport Mazda Performance Blog

July 8, 2013

Inside the upcoming CorkSport Blow Off Valve

When you look at the blow off valves (BOV) and bypass valves (BPV) on the market today you see many examples of the same thing with little to no innovations. For those of you that aren’t aware, BOV’s and BPV’s are valves that vent pressurized air in the tract between the turbo and the throttle body. This prevents the turbo from suddenly stopping or slowing as those can cause unwanted bearing wear on the turbo. A BOV vents this pressurized air into the atmosphere (into the engine bay). A BPV vents that air back into the intake just after the mass air flow (MAF) sensor. Venting back into the intake allows the ECU to correctly meter that air that it has already accounted for. Many times when venting to atmosphere you can get a momentarily rich condition because the ratios are off.

We were talking about innovation though, the last great innovation in valve technology for turbos was probably years ago with pull type valves like the SSQV from HKS. Many years have passed since then and not much has changed, outside of the few valves that partially vent to atmosphere and route the rest back to the intake tract. Typically now you just see one copy after another of someone else’s idea. SURE, it can be hard to innovate in the blow off valve market but we were convinced there was something exciting we could do.

We speak often about your ideas sparking our innovative minds, this project was started by just one of those customer suggestions. We started with a customer submission of using wave springs that led us to design a new valve design to reduce the size and weight of the moving parts.

Key Features of the upcoming patent pending CorkSport Blow Off Valve:

Reduction of spring height

With the use of a wave spring we are able to reduce the spring height by 50%. The traditional spring sits at 40mm and the CS wave spring sits at a 20mm height. These springs both provide the same force and will move the same distance before experiencing coil-bind.

Reduction of piston size

Because the spring is 50% smaller we are able to reduce the piston and still maintain the same amount of movement. As you can see, just changing to the wave spring we were able to decrease the piston by 33%!!!

What does that all mean?

The reduction in mass is all well and good, but just being smaller isn’t the only benefit (even though that is pretty cool). With the force (F) being the same and the mass (m) decreasing by 33% we can see how the mass relates to acceleration (a) in the formula F=ma. Rearranged, this becomes a=F/m. This means we have accelerated the actual speed of the valve, which means the valve is able to react much faster than a larger valve with a traditional spring (33% faster!) Because the blow off valve is a safety feature to protect the turbo from premature wear, this increase in acceleration can help increase the longevity of the turbo and the system as a whole.

What does all this innovation look like?

With the reduction in the size of these key parts, we can reduce the body size. This can be especially helpful in situations with airboxes, custom turbo and intercooler kits or even in universal situations where space is at a premium. Below you can see a comparison of similar BOV’s, the spring chamber on our design is significantly smaller but the function is not lost; in fact, we improved it!

To maximize flow, we pushed the piston area out to ensure a larger venting area, this reduces the time it takes to vent the air and allows larger turbos to vent more efficiently. As a blow off valve, this certainly pushes the envelope, we think we can find even more applications for this kind of innovation. We are very proud to be able to offer things for the Mazda market we helped create and will continue to engineer parts that push the scene for you.

July 1, 2013January 11, 2020

Dual Product Release!! CorkSport Shift Knob and MazdaSpeed 6 Rear Differential Mount

After months of testing and making sure it couldn’t be broken, we are finally ready to release the CorkSport Mazdaspeed 6 Rear Differential Mount!

With all the testing we have done on this part, we know it is the strongest available on the market, but don’t take our word for it. To quote Dennis Gardener, who tested this part on his Mazdaspeed 6 equipped with a GT35 turbo: “I threw everything I had at this mount and my engine blew up long before I could even make a dent in it.”

Machined from lightweight billet aluminum and anodized black, the Rear Differential Mount from CorkSport is durable and built to last. Priced below the cost of replacing the stock mount, the CorkSport Rear Differential Mount is ideal for all Mazdaspeed 6 owners, especially when you start turning up the boost!

The CorkSport Mazdaspeed 6 Rear Differential is available at https://www.corksport.com/corksport-mazdaspeed-6-2006-2007-rear-differential-mount.html

The CorkSport Shift Knob provides smooth throwing shifts, and clean style to complement your Mazda.
Weighing in at 320 grams, the CorkSport Shift Knob provides easy weighted throws that improve response and feel. Shift smoother and let gravity help with extra weight in the palm of your hand. With soft leather, and baseball style embroidery the CorkSport shift knob will complement your interior and feel good in your hand. Works great with your Mazda or Mazdaspeed.

The CorkSport Shift Knob is available at: https://www.corksport.com/corksport-shift-knob.html

May 24, 2013June 1, 2023

Grams Per Second Explained

At CorkSport we’ve had a lot of questions over the years about mass airflow (MAF) signals. Including some great discussions about a pesky measurement called grams per second (g/s) and what that really means. There is a lot of interesting misinformation out there that we have heard and wanted to take the time to explain how grams per second actually work and what it really translates to. To understand what grams per second really is, we will first discuss where the reading comes from.

CorkSport Mazda SkyActive Short Ram Intake CX5 Mazda 6

When you are logging a MAF signal you have a few options. One is MAF voltage and one is MAF signal. They are really the same thing, just expressed in different ways. The MAF sensor itself is a 5-volt system that gets a signal from the air traveling in the MAF housing. A typical MAF sensor uses a wire or film that is heated electrically. The incoming air cools the element to which the sensor has to regulate; this regulation lets the ECU know how much air is going through the engine. This voltage is then converted in a table stored in the ECU (Engine Control Unit) and this is where you get your g/s reading.

Now for the fun part: when you purchase an aftermarket short ram intake the MAF housing shape and diameter determine the voltage reading and thus the g/s reading. If the housing has been engineered correctly then the reading should be fairly close to the factory reading. Often the factory runs cars on the rich side for fueling when they are in open loop. The sizing of the MAF can be adjusted to create more power at the top of the rev range by leaning out the air/fuel mixture. The MAF signal also is a major part of calculating load values which control timing and most other functions of the engine. This is not a part that should be taken lightly or changed indiscriminately. In our extensive testing we have found that even half a millimeter in diameter of a MAF can cause measureable differences.

The g/s reading can also be used to check power-increasing mods such as exhaust or intercoolers. If you log power runs you can see the g/s increase with different mods. Although, be careful when comparing data on the same car. If you aren’t testing on the same day or conditions you can see slight differences because of air density or other environmental conditions. Unfortunately, when you want to compare different intakes you will not be able to show an apples-to-apples comparison. Because the MAF housings are not the same sizes between brands the signal will be different. If you check a MAF housing that is larger than stock you will read less g/s and one that is smaller you will read more g/s. Simply put, when comparing different intakes or any other factors that are different: Grams per Second does not equal power.

With all the complications in making a MAF to perform exactly how you want, we chose a one-piece fully machined aluminum MAF housing. This way you can precisely control quality and sizing. Then by creating an air straightener that is injection molded, we can have the most control over our MAF signals. There can often be issues with purchasing lesser quality MAFs housings that are welded together or bolted to pipes. Not only can you have leaks but you cannot preserve the shape perfectly. Look for more intake articles and an explanation of what a big MAF intake is and when you actually need one soon.

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April 25, 2013February 28, 2018

Fuel Pump Comparison Part 2

In part 1 we discussed fuel pumps, their uses and what’s inside them. Now we can talk a little about what goes into making them and what the differences are.

Does size matter? When looking at the stock piston on the factory fuel pump you can sure say that it does matter. If you increase the piston diameter you increase the flow of the pump. We have decided to compare the similar internals first and then compare the APR pump afterwards. The Autotech/KMD internals use the same diameter piston head. At 9.8mm compared to the factory 8.0mm. When comparing the volume area they are both about 50% improvement with the KMD edging out the Autotech by a marginal amount. This slight edge comes from the shape of the end of the shaft being slightly different. The Autotech looks more like a piston from an internal combustion engine where the KMD is very similar to the factory design at the end. Because these are the older version of the KMD internals they are coated differently. They look to be a TiCN coating but we can’t say for sure. The Autotech internals are listed as a DLC coating which stands for Diamond Like Carbon. The newer KMDs are now PVD coated (Physical Vapor Deposition).

When we start comparing the sleeves that the piston rides in we notice they are all similar in shape and size. The Autotech has a coated sleeve that appears to be some sort of tool steel. The factory is uncoated and appears to be tool steel. The KMD is uncoated and appears to be stainless of some variety. Internally there is a relief cut that is ~3 times larger on the aftermarket internals which should help with the 50% improvement in flow. The sleeve shows the constraints for why you can not go much larger than the 9.8mm piston. The end that fits in the factory pump can only be so large and the wall thickness must maintain a certain size or failure will be imminent.

For a long time the CP-E pump was rumored to be made by APR. The CP-E pump we ordered actually came with an APR sticker on the side of it. Oops. We quickly disassembled it and documented the findings. The pump uses a 9.5mm piston which is smaller then the two internal only options. APR claims 40% improvement and we calculated about a 41% improvement so no issues there. They also chose a Stainless steel sleeve and DLC coating on the piston. The big difference comes when you look in the cap. They machine in an extra Seal to help with the oil deposit issue. Is this needed? We aren’t sure yet but it is an interesting addition.

Now for the one big addition that only one manufacturer saw fit to think about. APR added a spring that increases the ability to return the piston. This can be very important for wear on the cam shaft if you get any float from the spring at higher RPM’s; the more the pump worked, the more important this would be. Remember that the cam has three lobes on it so even though the cams spin at half the speed of the crank the pump spins at three times that of the cam. This makes a 1.5 times the crank difference. So what ever the RPM you are at the pump is at 1.5 times that. At a 8000rpm redline the pump is going 12000rpms. The pump also has to draw in 40-50% more fluid so a return spring plays apart in that as well.

Next time we will get these pumps on the dyno and check out how the hold pressures at the same load. Luckily we have an in house dyno that can vary load and the ability to log pressures.

April 23, 2013

Help CorkSport help you!!!

Here at CorkSport we know you, the customer, are what really drives our business. We don’t just build parts we think you need, we build parts YOU ask for. We understand Mazdas and we love to innovate, but some of the best product ideas we’ve ever had, have come from our customers. We’ve gone to great lengths to make sure we stay involved with you and have a genuine interest in the parts that you want. We’ve set up a link on our website to help make it easier to get your great ideas to our great engineers. If you go to our site and scroll down to where it says “Collaboration” underneath it is a link that says “Request a Product”

We’ve worked hard to make sure we provide exciting products that live up to your expectations and who better to tell us what’s needed then the very people who get excited about it? In the past we’ve worked with our customers to decide everything from the colors we offer for our upcoming brake caliper kits to sending out test parts to customers with high horsepower to try and see if they can expose any weaknesses that we may not have seen.

As we ramp up for the race season we want to make sure your voice is heard and you get the best from us. Please feel free to add your suggestions online, email us or even pick up the phone and let us know what you think. We can’t wait to see what amazing things we can do together with you this year!

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