How Not To End Your National Championship Race

SCCA Runoffs Touring Group 4

In September, CorkSport participated in the SCCA Runoffs, the largest club race event held every year. In 2016, the Mid-Ohio Sports Car Course hosted the event in Lexington, Ohio. Having only raced there in a simulator, we spent two days testing at the track the weekend before and received coaching from Will Dodd, a local Spec Miata racer who has spent plenty of time getting to know the course. After trying several setup changes along with the awesome BFG rain tires for the first time on our Mazda 3, we felt pretty good about our odds of placing higher for qualifying.

SCCA Runoffs 2016 CorkSport Mazdaspeed
Credit: Melissa K Lepper

The runoffs format is made up of four qualifying days followed by a one-shot, winner-take-all championship race. For the Touring 4 group there were 34 people entered, which made for great racing no matter where you were in the field. The T4 field also shares the qualifying session with the B-Spec class, which adds excitement catching up to them on the track with the higher top speeds of the T4 cars.

SCCA Runoffs Touring Group 4
Credit: Melissa K Lepper

Qualifying session #1

On the out lap, an Rx8 blew a line off his oil cooler and laid down a puddle in turn two (aka the keyhole) and proceeded to drive down the straight before he went off in turn four. This meant heading into four you were staring at a car in the gravel, the fastest spot on the track heading into a heavy brake zone. Not a good place to go off. The session should have been called with the oil down but the stewards let us run around the track, which was a waste of time. The best time I managed was a 1:47.84 — horrible for T4.

Qualifying session #2

The bad part about qualifying poorly in the first session is you are placed in order of speed from all of the days of qualifying. This meant I was sitting in 22nd behind several drivers I knew I could beat, and I would have to get a fast clean lap. After six laps I cleared the other cars and caught up to the B-Spec cars, which made me back off a bit. This was a bummer, since the predictive lap timer in the car showed I was on path to run a low 1:42 time.

The end result from Q2: I was in 18th with a 1:43.107. After the session was over, I was pulled into tech to make sure my car was in compliance with the rules. After 60 minutes of tech fun to make sure my car didn’t have a spool, the fuel was from the track, my ECU was stock, and we were cut free. Lucky for me they didn’t find the nitrous tank hidden in the trunk. (J/k)

Qualifying session #3

I went faster and was consistently in the 1:42s, but everyone else went faster as well. I slid back from 18th to 19th. Boo!

Qualifying session #4

Last chance to make a difference on Thursday. We went over the car setup and made sure we were in the best shape for starting higher in the field. In the end it didn’t make a difference. I got caught in traffic and struggled with the car. I was going to be starting 19th. There was one bright spot though: The top speed I hit was one of the highest at 120.8 mph going into turn four, which means I was exiting the keyhole carrying more speed.

Race Day

After getting new brakes installed on the car and running a hardship lap to make sure everything was good, we were set to race. Will noted that being on the inside at the start was a good place to pick up after going through Madness (corner five) and into six due to the track line and the width of the track. Being in 19th, I was on the inside to start.

SCCA Runoff Corner Five "Madness"
Credit: Melissa K Lepper

The start went well; I got the jump on a few Rx8s and moved up a few spots heading into four with a Pontiac Solstice in tow behind me. So far so good. I got though turn nine and the Pontiac was able to carry a bit more speed than me, so he went around the outside — a pretty hairy move but I saw him and left him space so he didn’t get run off the track. We proceeded to have a drag race when it happened. We made contact, and his right rear tire hit the side of my car at the driver’s door. We got wheel-on-wheel contact that spun him across my front and took his tire bead off. He went spinning off the track towards the wall.

I had hit the brakes so I wouldn’t punch his car in the door with the front of the Mazda 3. My car was pulling hard to the left; his hit wheel had punctured my left front. In a live track with a race going on, stopping is not an option. So in an effort to not cross the track to get to pit lane, I opted to pull into the middle of the track at turn 12 and park behind the wall to wait out the race.

I had my phone in my car, which prompted me to post this video while I watched the finish.

The other driver was able to pull into pit late. I was happy to see he did not hit the wall. I was able to talk to another racer I know who caught our contact on his camera. He was willing to share it with me.

This wasn’t the way any racer likes their week to end but it is racing. You never know what is going to happen out there on the track.


Derrick Ambrose, CorkSport, Mazda

High-Pressure Fuel Pump Troubleshooting

Good day, my fellow Mazdaspeed enthusiast! Vincent here, back at it again with the white Vans (just kidding, I wear Nike). In today’s tech blog, I want to talk fuel pump internals. No, I am not here to debate whose internals are better or what brand offers what. I am here to help you track down and correct your low fuel pressure issue. Now, it’s no debate that anyone who’s anyone in the Mazdaspeed community will always recommend a high-pressure fuel pump internal upgrade before you start to go crazy down the mod list. But why do we want them and, more importantly, how do they work? I can confidently say that a majority of people who buy and install upgraded fuel pump internals do so simply because they are suggested it by their tuner, a forum, or a friend, but a very small percentage of people understand how they actually work, and how to correctly diagnose a problem should they ever have a fueling issue. So, grab a seat, and let’s dig in.

Continue reading “High-Pressure Fuel Pump Troubleshooting”

Troubleshooting Issues with Your Mazdaspeed Boost Control Solenoid

Having trouble with your mazdaspeed EBCS? Here are the most likely issues and how to fix them.

Good day fellow boosted enthusiast, Vincent here with CorkSport Mazda Performance. Today, I want to share some expert advice with you on diagnosing boost control issues with your turbocharged Mazdas.

I would venture to guess that about once or twice a week, my team and I get a phone call here at HQ related to customers who are trying to diagnose a boost control issue with their electronic boost control solenoids. Whether it’s too much boost, not enough boost, or random and sporadic boost signals, a boost control issue can have you digging around your engine bay for quite some time if you don’t have a good diagnostic procedure.

This blog is intended to function as an aid in diagnosing boost control issues. If you’re interested in a more thorough understanding on how an EBCS works, check out this white paper that one of our engineers wrote. Now let’s get to it!

To start, let’s have a quick review on what an EBCS is and isn’t.

The EBCS is a unit composed of an electrically operated solenoid housed in its own little manifold designed to regulate and route boost signals to the appropriate area in the engine bay. The EBCS is not the mechanical device that physically moves the wastegate flapper to re-route exhaust gases around the turbine wheel, that’s the job of the Wastegate actuator.

Now that we cleared that up, let’s look into some possible causes for poor boost control issues.


I can’t stress this one enough. I would say a bad or improperly routed vacuum hose is the root cause for about 70% of all issues. When diagnosing a boost control issue, start with a visual inspection of all vacuum hoses in the system. Any hoses with nicks, tears, rips, or cuts should be replaced with a good quality silicone vacuum hose. Silicone is preferred because it has a longer life than a traditional rubber hose and tolerates engine bay heat better. Also check to make sure the hoses are not pinched in between anything. I’ve seen cases where a signal hose gets trapped between a nut and stud of some sort, causing it to be completely pinched off and rendering it useless. So make sure your hoses go from point A to point B clearly and perfectly with no stops.



Since we’re on the subject of hoses, let’s also be sure that we’re routing them correctly. Each hose is meant to take some air from one place to another in a particular fashion. Often times guys and gals get in a rush and just start plugging in hoses wherever they see empty spots. This is especially evident on the EBCS unit itself considering there are 3 ports on it that are all very close to each other and it’s quite easy to put the wrong hose on the incorrect port. This is where a good set of high quality instructions becomes helpful, so you always have something to reference.

Important note: Make sure to reference instructions specific to the brand of EBCS your vehicle is equipped with, not all controllers designate the same letters and ports.


Isolate the problem

If you’re dead certain that the above two points check out, then the next logical step is to isolate the problem. What I recommend is to set your turbocharger to run off of spring pressure only. What you would be doing here is running a hose from the compressor cover to the lower nipple on the WGA and then putting a vacuum cap on the other port of the WGA. When this is done, what you’re doing is isolating the mechanical side from the electrical side.

If we perform this and our car runs 100% hitting the targeted spring pressures, then we can check off the turbo or WGA as being the issue and we can return our focus to the solenoid and its components. If when we’re in this set-up and still experiencing a boost control issue, then we want to check out the turbo and its related components. Things to check are the WGA flapper for any binding or contact, and the turbocharger itself for any mechanical issue such has damaged wheels or housings. Also we want to check any boost tubes, intercooler piping, connections, etc. to make sure it’s not skewing any of our signals.

Fix the problem

If you get to the point where you feel the EBCS unit itself is the problem, a simple thing to do (if you have the ability to) is to bug a friend. Say your buddy is running the exact same EBCS as you, ask him to borrow it for half an hour and swap it in. If we leave everything as we had it and swap solenoids, and our problem goes away then we have a really strong reason to believe the controller is the issue and it should be inspected. This is the point when you would want to contact the manufacturer so you can send it to them and have them test it. Don’t try to take it apart yourself! Almost all solenoids have really tiny and precise O-rings that can break easily if mishandled.

These are just some of the most obvious and most likely things to check. Before going to crazy, you still want to be sure that you have a healthy engine and no other forced induction problems such as a massive boost leak somewhere that can skew results.

I hope this blog was helpful and can be useful to some of you. I leave you with some last minute points.

  • When diagnosing, change one thing at a time to eliminate variables. You don’t want to jump in and change 10 different things and hope for the best. You’ll just waste time and resources.
  • Double-check your tune. When switching to an aftermarket EBCS, a tune will be required since almost all aftermarket units work faster and are much more precise than an OEM unit.
  • In regards to vacuum hose length, I can say for 99% of you it won’t matter. Unless you’re running 20+ feet of hose, the length itself will not affect your signals. At the tiny sizes we’re using, you’ll need lots of hose for length to make any noticeable impact. My recommendation is to use just what you need for a nice clean set up, no more and no less.



Your Suspension Questions, Answered

We get quite a few comments (okay, a ton) on our reviews and FAQs page asking questions like: will these wheels fit, will my car scrape, what do I do after I instal, etc. With so many questions coming in recently, I wanted to address this topic.

Will my car scrape speed bumps?

With any of our CorkSport springs sets, you shouldn’t have any problems with normal traffic control devices if taken at the posted speeds with stock Mazda body work. If you try to be Ken Block in your Mazdaspeed 3 and launch the car at 75mph you will scrape on the launch and landing.


Will my wheels rub?

With the OEM wheels, you won’t have any rubbing problems with our springs. We engineer our springs to be comfortable and most have an increased spring rate of 5-15% over OEM. With the car sitting lower, it’s possible to hit bumps with a heavy load but you shouldn’t rub unless you have a suspension alignment problem. On the second gen Mazda 3/Mazdaspeed 3s, the rear acceptable suspension range is already wide and if you plus size the diameter and wheel width you can run into some clearance problems. We found after an installation of the springs, the rear camber was -2.2 degrees on one side with no rubbing and -1.0 degrees on the other side with rubbing. To fix this, a set of adjustable rear camber arms is required to set the suspension even between both sides to give the wheel clearance and keep the alignment within specs.

Will these wheels fit my car?

Let’s make this easy. Go to and punch in the numbers. Google is your friend. Use a tape measure to see how much clearance you have on the inside against the suspension and the outside against the body work.

Will I need aftermarket wheels to run your springs?

You will not. We test our springs on the OEM wheels for all Mazda models we offer springs for.


Will I need to align my car after installing the springs?

Yes, you will. The toe settings on the suspension will be affected which will cause excessive tire wear if not corrected after installing any lowering springs.


Will I need to roll my fenders/guards/wheel wells?

If you want to run a different offset wheel, and the clearance is going to be tight, it’s a good idea to roll them. You won’t have to roll your fenders with the OEM wheels.

Have a question we didn’t answer here? Feel free to post a question in the comments or in the FAQs page of our website.

Meet Derrick from CorkSport. Loves racing, Mazdas, and his CS fam.


Ask the Expert: CS Engineer Drops Knowledge

We asked the CorkSport community for their ultimate Mazda performance questions for our new series, Ask the Expert. From the good to the bad to the weird, here are the top four questions straight from CS fans and our engineer’s answers.

Your top Mazda performance questions answered by our experts.
Owner: @sikemantana Photography: @konceptphotography

Q: What is the maximum horsepower you can get from a MazdaSpeed 3 with just bolt-on’s?

A: With the typical bolt-on performance modifications from air filter to exhaust tip, you should be in the 320-330wHp and 340-360wTq range. You may be able to up those numbers a small amount with an E85 mixture, but for some locations that is not readily available. This is not including an exhaust manifold, intake manifold, or larger turbocharger. Now, if you were to add the exhaust manifold, intake manifold, and larger turbo (this being the largest power gain) then you will quickly find the limit of the fuel system at the 380-390whp range depending on the fuel grade/type.

Q: Will a supercharger/turbocharger kit become available for the SkyActiv platform?

A: This question has been stirring around since the release of the SkyActiv platform. With the release of the MX-5 with the 2.0L in the U.S. and the 1.5L in foreign markets I would not be surprised to see a supercharger and/or turbocharger kits being released in the next 1-2 years.

Q: What’s the boost threshold on the CorkSport Performance Drop-In Turbocharger?

A: We don’t have a compressor map to quote from, but I believe I can answer this fairly accurately from my knowledge and experience. The CorkSport turbo will be the most efficient in the 1.75 – 2.25 pressure ratio range. This equates to approximately 11 – 18psi, but this doesn’t mean the CS turbo will fall on its face in the higher boost levels.  Due to the more efficient design of the forged billet compressor wheel, the CS turbo should stay above 75% efficiency until around pressure ratio 3 (30psi), and then begin to fall off a bit.  At around pressure ratio 3.5 (36-37psi) you will be very close to the maximum shaft RPM for safe operation, so I wouldn’t push it past that. Either way, if you are running the CS turbo above 30psi, then bravo sir. I’m sure you have a very fun car.

Q: Here’s a hard one. If I have a manifold, which calipers should I buy to get a better exhaust sound?

A: Well the issue is you weren’t clear enough with your collection of parts. First off, what kind of manifold are we talking? Is it the manifold forged from Unobtanium with the blood, sweat, and tears of Santa’s Elves or is it the one and only manifold hand fabricated of carbon nano-tubes in the R&D lab at Koenigsegg designed by the alien race called…The Stig? And then you have the caliper… Do you mean the kind that grip locks the ferrous circular structure utilizing kinetic friction to cause conductive and convective heat transfer ultimately converting mechanical energy into thermal energy until it comes to a squealing stop or the kind that measures to the 0.001” and was used to design aforementioned caliper? See how I’m a little confused? Now we have four combinations to pick from and I could explain each and every one of them in great detail, but I don’t want to bore you. So the one I would pick goes as follows: Your cold start announces your presence like the trumpet of the Greek God Zeus riding his chariot into battle followed by your WOT pull roaring like a thousand lions chasing down a heard of Zebras.

What other performance questions do you guys want our experts to answer?