GrimmSpeed

Good stuff, guys! I agree 100% with the IAT sensor bung. I run speed density myself and having some extra meat designed into the casting for threads will be excellent. Also, got some goodies from our pals at Turbosmart today! We will be guaranteeing TMIC/Splitter fitment with their Dual Port BPV, which sits just under 4.5in tall off the flange face. That should give you dudes plenty of room. Matt Beenen Engineering

Great to hear! Haha, thanks? I try to keep it as basic as possible without losing content/meaning. Any specific questions? Awesome! We're a pretty picky group over here too. Answered you over on NASIOC, but we'll have some good, clean, comparison numbers for you. Additionally, MotoIQ has been testing our 02-07 TMIC for that last couple of months and they'll have some results and a review available shortly. I'll do my best! Yikes! No engineer here would get away with garbage like that. You pretty much nailed it here. It's a tough balance and for a guy like myself, that doesn't like settling, it's hard to make a 'catch all' TMIC. The companies that claim to have done so are lying to you. That said, with proper design, you can make your effective range as wide as possible, which helps a lot. I used to be in the same camp as you. In fact, my own personal car makes around 600whp and I run a TMIC. For what it's worth though, this same design methodology worked out pretty well with our 02-07 TMIC. We have a tester car making around 600whp on our TMIC and E85. He made 521whp on the Karl Performance Superflow in SAE correction. Tuned by Graham of Boosted Performance. Since then, he's done cams, headwork, more boost and more aggressive timing. No fluffy dynojet number here. Really appreciate the input though and like I said, I don't totally disagree. We should be able to design a TMIC with a sweet spot between 250whp and 550whp or so (with a target of 400whp dead in the middle) without trouble. Obviously it would support more or less, but less efficiently. To be perfectly honest, at less than 250whp, your stock TMIC is likely not your limiting factor. Sounds like we're on the same page! I've got some more analysis as well as some progress on the design to share. I'll get my ducks in a row here and post it all up early next week! Lots going on at GrimmSpeed these days. If I didn't have one of you swinging by tomorrow for some radiator shroud measurements, this TMIC thing might more along a bit more quickly. Matt Beenen Engineering

Thanks for the suggestion, fellas! It's definitely on our wish list, but right now, we need to know that the sales volume will be there. Tooling for these castings is very expensive and newer markets can be quite risky! Don't worry, we haven't forgotten you! Thanks for the honest input. In the same spirit, I'll tell you that this will not be a $399 TMIC solution. With all that will likely be included, manufactured in Minneapolis, MN, it just isn't possible. Sorry! Agreed. We'd like to make sure that we provide a good option for folks on stock turbos wanting an upgrade but also that people wanting to make some serious power can find success with this top mount. It requires a good deal of analysis to build something with that range, but I think we can do it! I'm picturing something with a little bit more capacity (flow and cooling) than the PW and substantially higher build quality/better fitment. We love easy installation, t-bolt and minimal fuss. I think we'll have you covered! We agree, 100%! Thank YOU for the support! This is an awesome offer. For the right guy, we may even be able to come to a special pricing arrangement in exchange for the testing. Let's keep this in mind as production nears. Enjoy your vacation, Dave! Rock on! Perfect feedback! Thanks a lot! Matt Beenen Engineering

Man, you guys are going gangbusters in here! I've got answers for all of you, but I may not be able to get to them until tomorrow. For the time being, here's some food for thought regarding sizing. Intercooler Sizing As air is compressed by your turbo, it heats up, not because of the heat of the turbocharger, but because as the air is pressurized, the air molecules are forced closer together and that results in an increase in energy. This energy manifests itself as heat. The function of an intercooler is to remove that heat from the intake charge. Removing heat from the charge air means that your intake charge becomes denser, making more power and reducing detonation. The proper sizing of an intercooler core is a careful balance of airflow and cooling capacity. When it comes to comparing an intercooler’s capacity to perform efficiently, it’s important to talk about both of these factors together. Simply quoting a volume or maximum flow rate does also no good. A well rounded design is one that removes heat efficiently without creating a pressure drop that negates the gains from doing so. The main factors that come into play here are heat transfer area, internal flow area and internal volume. Heat transfer area is the total area of all of the fin packs and plates in the core. Internal flow area is pretty straight forward. This is the total area that charge air can flow, internally, through the core. Lastly, internal volume is simply the flow area multiplied by the channel length. Larger internal core volumes contribute to turbo lag and a loss in throttle response, as the entire volume must be pressurized before that amount of pressure will exist in the intake manifold. Now, we’ll take a step back and calculate, roughly, a few of the variables that exist in our specific application, in order to determine requirements for maximum flow rate and cooling capacity. My goal here is to create a table that shows CFM requirements at a given RPM and boost level. To do so, I’ve made a few assumptions about volumetric efficiency, ambient temperature and adiabatic efficiency. These calculations will at least give us the framework to move forward confidently. Below are some applicable equations. http://www.grimmspeed.com/images/product_images/tmic_subaru_sizingeq_1.jpg As you can see, we use an air density ratio to accommodate for the fact that only in an ideal system do the pressure ratio and density ratio rise together. This is where a carefully designed intercooler (and a properly sized turbo setup) will help. The closer we can get the two ratios, the higher our efficiency. Back to numbers. Below is an example, using out calculations, for a 2.5L Subaru producing 27psi at 8000rpm, assuming volumetric efficiency of 80%, ambient temp of 80F and 90% compressor efficiency. Boost Pressure = 27psi Pressure Ratio = 2.84 Ideal Turbo Outlet Temp Rise = 185.34 Actual Outlet Temp = 285.93 Air Density Ratio = 1.85 Airflow Rate = 518.62CFM So now we have a flow rate. We’ll add a little headroom and round to 550CFM for simplicity. Now, there isn’t any particular equation that will tell us exactly what size core we need based on a CFM requirement, but there’s a good amount of historical data and it’s been compiled into a single chart by Corky Bell in his book, “Maximum Boost”. This chart takes both cooling capacity and pressure drop (among other things) into account. Again, remember that all of this is to determine a starting point and some sizing framework. The actual size that we decide to use will be greatly influenced by the space claim available in the engine bay. http://www.grimmspeed.com/images/product_images/tmic_subaru_flowareachart_550cfm.jpg What you can see is that an internal flow area, according to Corky Bell, should have a minimum flow area of around 22sq in. with closer to 28sq in. for an intercooler of typical density. Without our rounding these figures change to about 21sq in. and 26sq in., respectively. For reference our 02-07 TMIC is pretty dense and has 30sq in. of internal flow area. This has supported over 600whp, so our math is right on track. Here is where things get tricky. Below, I’ve taken measurements of the stock TMIC along with a few of the current aftermarket options. OEM TMIC Core Thickness = 2.25in Channel Width = .20in Channel Length = 10.75in Number of Channels = 16 Internal Flow Area = 7.20in^2 Total Internal Volume = 115.20in^3 PW TMIC Core Thickness = 3.52in Bar Thickness = .25in Channel Width = .27in Channel Length = 15.50in Number of Channels = 10 Internal Flow Area = 8.15in^2 Total Internal Volume = 126.39in^3 It’s worth noting that if we go back through our math and use values typical of a stock 2.5L, turbo Subaru, we find a maximum air flow rate of around 240CFM. According to the chart above, this flow rate, with low density fins (stock intercooler) demands a flow area of about 10sq in. This doesn’t tell us much except that the factory intercooler is sized about right for the job. It’s unlikely that they sized it for maximum performance at redline, so it’s understandable that they actually fall a bit short in flow area. If we can get these flow areas closer to ideal values, we can reduce the amount of work that the turbo needs to do to provide the same amount of boost to the intake manifold. This will not only allow the turbo to work more efficiently, but will also reduce compressor outlet temps. So, we’re at a point where we need to consider a number of different fitments that might allow for a large overall core volume, but also for a flow area that will adequately and efficiently support a wide range of power levels. Feel free to poke holes in what I’ve got typed here and let me know if you see errors or areas where clarification may be of use! Trying to keep this technical but relatively basic! Matt Beenen Engineering

If a splitter will aid in the effectiveness of whatever we design, then a splitter there shall be! As for fitting other aftermarket TMICs, I can't comment yet. There are a few unique designs and it would be quite difficult to accommodate them all. We will see though! Thanks for the support! We always do our best to provide unmatched quality and fitment in an affordable package. Anybody that's seen our 02-07 TMIC can attest to the quality and craftsmanship that go into them. THANK YOU very, very much for the valuable input. This is the reason I came to you guys before firming anything up! You and I think alike. I agree with you on the heat soak issues. I can't comment on the strut tower bar, as I haven't done any testing myself. That said, I'm going to do my best to leave some room for a few of the more popular STB options. Please follow along in this thread and continue giving your thoughts and feedback! Awesome! I 100% agree on the BPV bolts. Do people really do that and rely on the threads to seal? Talk about a terrible design! Hose kits are a must! As for making it look pretty, I've found that prettiness tends to follow careful design and top-notch craftsmanship around. You WILL NOT be disappointed. Hell, Justin Grimm himself has one of our 02-07 TMICs displayed on a shelf in his living room! As for the 5 year old boy, let's give him a little bit more credit than that. I'd say 12, at least. Perfect! Great feedback! I'm hearing a common theme regarding the concern for BPV/BOV fitment on the PW units. Is that a big problem for them? I've only fitting one with a stock BPV. Stay tuned for updates! I'm hoping to post some sizing calculations and information today or tomorrow to see how you guys feel about it! You engineering/thermodynamics freaks, please pay extra attention; I'd love to have someone else checking our math/theory. That said, did you guys see Justin North's STI swapped RS on our facebook page yesterday!? He's making 600whp on our 02-07 TMIC, so we must be doing something right! Matt Beenen Engineering

How about I copy/paste my response to you for the good folks here? Thanks for the great feedback/input! We will definitely do our best on the strut tower bars, BPV fitments and aftermarket turbos. What strut tower bars are most important to you guys? We'll track a few down and keep them on hand for testing! Good stuff. We will definitely address heat soak as well as we can. At a certain point, though, there's only so much you can do. When your car isn't moving, your TMIC becomes nothing more than a chunk of aluminum in your engine bay! Matt Beenen Engineering

Reserved for future use again!

Reserved for future use.

Well, immediately following the successful release of our 02-07/08+ STI TMIC (top mount intercooler), we heard an overwhelming demand for a GrimmSpeed 08+ WRX/LGT style TMIC. Instead of simply slapping something together (not our style) and making it available to you guys, we thought it would be best to slow things down just a bit and get some real input from you, the end users. We have an intimate understanding of what makes a great intercooler, but there are many decisions to be made and we’d really love to incorporate your input/knowledge as we move forward. Maybe we can all learn a thing or two! Take a minute to watch our product release video for the 02-07 TMIC. You can expect the same performance, quality and attention to detail with the project! [ame=http://www.youtube.com/watch?v=KtGfs6k9BzM]GrimmSpeed Top Mount Intercooler Product Release - YouTube[/ame] The first thing that we need to do is establish a set of primary design requirements. Here’s what we came up with. Of course, we have many other requirements as part of every product that we develop, but here are the heavy hitters on this particular project. The GrimmSpeed TMIC must fit 08+ WRX fitments without substantial/permanent modification. The GrimmSpeed TMIC must accomodate the use of upgraded ‘STI style’ turbos. The GrimmSpeed TMIC must be properly sized to support 550+whp. The GrimmSpeed TMIC must be innovative, providing features and capability that aren't already available. The GrimmSpeed TMIC must be an affordable solution. Other requirements that are typical of any GrimmSpeed product involve material selection and sourcing (locally, when possible), quality, visual appeal, innovation, etc. Here’s where you guys come in. We have a great deal of experience working with many different TMICs but we know that you do too. What are some design features that you’d like to see incorporated? IAT bungs? Water meth bungs? Splitter? What are some concerns you have with your current TMIC? Installation issues? Fitment issues? I’ve already got a long wish list, but I’d like to hear your thoughts before posting! What we’ve done so far is create a 3D working envelope in CAD using out FARO Arm, as well as 3D scans of a handful of OEM and aftermarket options to use for size/placement comparison. We already have a couple basic designs pretty well sorted out, but there is still a lot of room for change and revision. As we firm things up, I’ll share my calculations and design methodology, but I think it’ll be best to start with the basics and expand from there. After crunching the numbers, I have some concerns regarding the efficiency and cooling/flow capacity of every single 08+ WRX TMIC that I’ve seen and I’d like to get to the bottom of those before moving forward. Perhaps some of you experts will have some insight here. The intent of this thread is to gauge interest in the product, but more importantly, to better understand what your needs are. We know that there are already some great options out there, but we also think that they all fall quite short in one way or another. Now’s your chance to influence the design and development of what will become the new standard in 08+ WRX top mounts intercoolers! In the next post that I make, I’ll compile the suggestions that we’ve had so far as well as share some of the ‘hall of shame’ photos that I’ve collected and received over the last year or so. With that framework in place, we’ll nail this design and get parts in your hands! Being that we're in a technical subforum, let's keep this clean, civil, informational and educational. Sales or customer service questions/issues can be directed to sales@grimmspeed.com. We'll talk a bit about cost, but only as a design requirement/limitation, not in a sales/marketing context. Below are a just a few teaser photos that I've snapped while exploring a few ideas/options with this project. I'll post many more along the way! Matt Beenen Engineering http://www.grimmspeed.com/images/product_images/tmic_subaru_08_teaser1.jpg http://www.grimmspeed.com/images/product_images/tmic_subaru_08_teaser2.jpg http://www.grimmspeed.com/images/product_images/tmic_subaru_08_teaser3.jpg http://www.grimmspeed.com/images/product_images/tmic_subaru_08_teaser4.jpg