Cobb Tuning Mazdaspeed 3 FMIC (Front Mount Intercooler) Part 2 - Follow Up
 

Cobb FMIC Part 2 Update:

With nearly 11 days of real world testing on the streets of California, we're back to bring you some data. The last few days here in California has been well over 100F. Perfect for this kind of testing and although i tried to stay out of it much as i could, i had to get out there and see how the car reacted to the temps with the Cobb front mount installed. i was also able to capture some data in much lower temps as well as evening temps.

Prior to the install of Cobb FMIC, i had changed the setup of the car. Originally, an ETS 3.5" was installed on the car. I also had a manual boost controller set at 18psi and a map clamp. To conduct these tests, i chose to install the stock TMIC along with removal of the MBC and Clamp. I wanted to see how the car reacted to stock boost with the new FMIC as well as give an ideal scenario for the average owner who may not have these type of mods. Also, we wanted to collect some data from the TMIC and compare it to the Cobb FMIC.

Testing Methodology:

Although crude, we just don't have the extremely expensive test equipment like the big boys have. So, we must make due with what we have at our disposal. In the makings of this second half, I made arrangements to order better equipment for future tests, so at this time, we are using our trusty MSD Dashhawk loaded with V2.5 Beta 4 with all of the Mazda updated PIDs.

It should be noted that Cobb has helped MSD with their software in achieving better accuracy from the stock sensors. The unit itself is nice, gives you digital readings of sensors of your choosing, able to log 5 parameters during data logging and allows you to store up to 5 separate data logs at a time before downloading. It has several sample rates of 1250,2500,5000 and 10,000. Again, although crude, it works for this test to compare the stock TMIC to the Cobb FMIC since data was captured from both using the unit.


We chose Mazda specific PIDs during the test. They were Wideband AFR, Engine Coolant Temp, Boost Temp, Intake Aircharge Temp and Boost/Vacuum.


[multipage=Stock TMIC vs Cobb FMIC]

Stock TMIC vs Cobb FMIC:

So, let's get down to the nitty gritty of this whole test. I tooled around roughly for 3 days with the stock TMIC in place. I must say, going from the ETS 3.5 back to stock, was very noticeable. The question in my head was, will i notice the FMIC like the ETS?

There's alot of argument of which is better for a car. FMIC or TMIC. Both have their advantages and both, have their cons.

TMIC's cannot outflow a front mount simply because not only does it lack the needed surface area to remove heat, their depth is also limited to hood and engine clearance. Core thickness plays a part in how successful a intercooler can work, but so does length and height. Again, this all equates to surface area to remove unwanted heat. We've seen aftermarket MS3/6 TMICs that make a difference on the car, but going say from a 3.25 inch core to a 3.5 inch core, showed very little difference. The stock hood with the air scoop doesn't seal very well on the 3.5 thick core and unfortunately, doesn't give much air flow across the top of it due to the loss of depth. There is also some rubbing issues you may have to deal with.

Tmic's are easier to deal with when headed to the dealership for warranty work, but also can be a pain when it comes to a simple plug change. They also get heatsoaked very easily sitting at a light, since they rest atop of the motor and get zero airflow in that position. TMIC's also exhibit more restriction only because of the limitation of space we have in these cars.

Front mounts have less heatsoak while sitting still. They are great when it comes to less restricted flow, greater surface area for cooling, and can have virtually no turbo lag or spool delay. It's all about the design of the FMIC. They all are not created equal. If you are someone who drag races a lot, a FMIC is a good choice. Im a believer that a FMIC is even a better choice for road racers. A FMIC allows easier access to your plugs, cleans the engine bay up nice and tidy and can give you the edge in performance due to the flow and cooling characteristics. Greater care must be taken when owning a front mount, such as avoiding curbs, dips in the roads, road debris. Also, its a good idea to perform yearly maintenance consisting of flushing the core out from the inside with simple green to remove any oil ingested and straightening of the fins. This will ensure a properly, high performing core for years to come.

Front Mounts flow a lot of air, but at what cost? Well, depends on who manufactures the kit. Bigger isn't always better, i assure you, but dealing with a company who does their homework, pays off. Cobb is one of those companies who spent a great deal of time testing various cores. Pressure drop on their core is roughly .65. That is incredible and some will even argue, unbelievable. That's ok, the data is out there and if you look at the Subaru community, they too have front mounts out there that have just as low as a pressure drop, as the Cobb FMIC does for the Mazdapseed 3.

Boost Drop, Lag And Performance:

Im convinced that I've only seen roughly 1/2 pound of boost loss, if even that. Going through 15 days of data has shown me there was no loss in pressure between the two systems. Ive seen boost spikes in the 18-19 psi category just like i have with the stock tmic on there. Ive seen boost hold at 16 psi running spirited on some freeways.

Lag? I can honestly say, i don't feel lag. The Cobb FMIC transforms the car into something different and its alot more fun to drive than it ever has been. The powerband through the upper rpm range is incredible. There is no longer restriction holding the little K04 turbo from doing its thing. Power transition is smooth and plentiful. 2nd gear will just roast the tires if you allow it... something the stock TMIC will never accomplish.

Temperatures flat plummet while driving. Sitting at stoplights over the last 11 days has shown that although temp creep is there, just like a TMIC, its not as high depending on the ambient temperature outside. Below, you will see a chart of the Cobb FMIC sitting at various stoplights for over 6 mins. Note the different temps seen in different ambient temp conditions.


During all of the above conditions, the slightest forward movement showed temperatures immediately drop, and quickly. If you truly are concerned at all with heatsoak because you're a diehard racer, you have two really good options at your disposal. You can either run methanol/water injection which may keep you a few degrees above ambient, or design and install a intercooler water sprayer. Over the next month, we are going to do both.

[multipage=Temperature Data]

Temperature Data:

Like i had said, i had a lot of data to go through. Unfortunately, time is always a factor and i literally put in 20 hrs a day between a real job and running these forums. So let's get started with what we have captured:

Below are some stock TMIC readings i gathered prior to installing the front mount. Although near impossible to duplicate weather conditions exactly, i did the best that i could do with the unpredictable, California weather:


The first thing we look at is the ambient temperature for that day. This was a spirited night drive while tapping boost between 3-5 gears. Each pull made here was roughly 15 or so seconds long, with a 15 minute delay between each one. As you will notice, even the stock TMIC was getting a bit hot as the inlet charge temp rose by the third pull. You see the lowest temp of 105 degrees and the highest of 106 on this run.


The next data table was done in the mid afternoon with an ambient temp of 74 degrees.


As you can immediately see, as the ambient temp increased because of day time, so did the boost temps. There is a drastic difference between night time air and day time air here in CA. Night time air is quite dense because of the moisture we have along the coast. Highest temp recorded was 123F with the lowest being 119F. Oddly, engine coolant temp didn't increase as it did on other days of testing.

Next we have a different set of data tables. These are measured simply by cruising with no boost:


[multipage=Cobb FMIC Temps]

Cobb FMIC Temps:

Now that we have seen how the stock TMIC handles temps while in and out of boost, let's look at the Cobb FMIC's data below:


Immediately, we see a higher ambient outside but the temperatures we basically the same as the TMIC at a lower ambient. We see the Cobb dropping down to 104F on the second run.

Next up, run #2:

I travelled down to the back side of a hill about 45 minutes later after the run above. I got out of the car and took a temp of the ambient air temp and decided to make a some runs back on the highway.


Here we see what running a front mount is all about. As the temps dropped outside, the core did as well. The day this run was taken, we had a relatively high humidity rate. The highest temp recorded was 101 and the lowest was 100F.

Now, let's look at some temps while cruising, no boost:


This is where we see the real advantage of our front mount. The core is keeping everything cool, whether we are in boost or not. The only real time our temps get out of control is when there is no air moving through the core at all. But, that will change real quick, the second your car begins to move.

Now lets look at some of the averages between the two intercoolers:


** Update **

I was waiting for an extremely humid morning to come to my area and finally it did this morning. At 3:48AM on 6/27/08 we hit 79% humidity, outside temp of 66F and barometric pressure of 29.89 inches. We have some pretty nasty weather here in Socal over the last 10 days.

I took Molly out to flog her and got her up to temp on a local toll road :) Operating temp was 188F and cruise speed was about 75 mph. Boost temp while cruising was 103F. I slowed down to 45 mph and began rowing through the gears. To my surprise, boost temp drop to 87F and slowly climbed to 94F before i hit the middle of 5th gear where i was slightly going over the posted speed limit.:dunno:

I'm amazed out how many times this FMIC can surprise me. I cannot wait to see data from across the US from users who are running this setup.

[multipage=Conclusion]

It's an absolute no brainer to consider this FMIC. This is one of two front mounts that we at mazdaspeed forums can honestly recommend. CPe is the other one. Although i wish we had an opportunity to compare both, we don't at this time.

What sets the Cobb out most is its price, performance and quality. At $999, its an absolute bargain. It is perfectly centered without any cutting or modifying of the stock bumper. It comes complete with stainless steel T-Bolt clamps to hold the charge pipes in place. The pipes are 2.5" diameter with rolled lips for the silicone couplers to adhere to, while also being powder coated to prohibit any corrosion while giving it a durable, long lasting finish.

After 11 days of flogging the car, NONE of the pipes have moved out of place from where i installed them, nor did any t-bolts loosen up. The car is a kick in the pants to drive more than ever before.

My goal was to fab up some shrouds and air diverters before i published this, but unfortunately, my materials have yet to arrive. So we will look back into these modifications later on and see whether or not they make a difference in the performance of this kit.

In closing, i would like to say thanks again to Christian and Josh over at Cobb. These guys are a great asset to our community and are open to any questions you may have with their products. Feel free to pop into the Cobb section of this site here and post up any questions you may have. Their kits are available to order now and should be shipping out this week or the next.