 I'm Emmy here again and welcome to another episode of Cobb U. Now throughout this series, we've covered component upgrades from intake all the way to exhaust that you'd want to do to get the most performance out of your car. Well, talk is cheap, so what good is teaching you, we can't show you by example. So today, we're going to take this stock 2012 Subaru STi and modify it with all the components and systems that we've covered to show you first-hand the kind of results that you could expect. We'll begin by running the car on the dyno to get the average stock power figures. Then our technician will install the new parts and then hand it over to our calibrator to tune the car and run it on the dyno again. As we've learned in the previous episode, we'll take our stock and modified figures to get the percentage difference, which will indicate how much power was gained. So let's get started. With our dyno pools and tune the car once it's modified is Mike McGinnis, who is our lead Subaru calibrator here at Cobb. So thanks for doing this with us, Mike. Absolutely, thanks for having me. Let's get to it, man. Let's do this. All right, so I'm going to get the car up to speed. We're going to do three dyno pools in a row. And then we're going to take an average of those three. And that way we know we get a nice consistent reading. So bringing the car up to about 2,000 RPM, get the dyno started recording, and I'm going to hit it. Let's take a look at our first run. 253 horsepower. Looks nice and smooth. OK, we've got a good start. We'll give the car a little time to cool down and we'll do another run. Awesome. All right, third gear, 2,000 RPM again. Here we go. Let's save that run. Pretty similar to the last one. That's what we want to see. So is this is this pretty typical to see the consistency like within like a Subaru? Yeah, absolutely. There will always be a small variation between run to run. And that's why we do the three and take the average. But the difference is going to be small. Cool. All right, we've got our third run. Looks about the same as the other two. That's what we wanted to see. And I think we're good here. Cool, let's go look at the results. All right. So what can we learn from looking at this? Well, the first thing that we were looking for was consistency over the runs. And we did get that. So as you can see, the runs follow the same trend. They are slightly different, but not that significantly. The next thing we saw, and I actually felt that a bit in the car, was a little bit of hesitation when the car first comes on boost right here. There's this little dip. So when we come, when we get back to tuning, I'm going to try to smooth that out a bit. Cool. Last thing, car made decent power for stock. But we're going to try to take it from here, all the way up to here, and then carry it out a little bit further towards the end of the graph. Nice. So when looking at this, what ended up being our average numbers? Sure. So for power, we had 253, 255, and 257 in three poles for an average of 255, nice tight grouping. And then for torque, we had an average of 242. All right, so let's take this car over, Justin, our tech, and get those new parts put in it. All right. For today's modification, Justin will be installing the Cobb Stage 3 plus flex fuel package plus some additional components. They include intake and air box, turbo inlet hose, front mount intercooler, up pipe, down pipe, cap back exhaust, electronic boost control solenoid, bypass valve, heat shield, a CSF radiator for added cooling, high flow fuel pump, fuel lines, fuel pressure regulator, fuel rails, 1050X top feed injectors, and flex fuel kit. The drivetrain received a new shifter with front and rear bushings and capped it off with a white Cobb knob. And last, front and rear slotted rotors and pads to stop all that new found power. All right, now that Justin is done with the install, Mike has our STI on the dyno. And we're going to do some tuning and some results. So where are we at? Cool. So Justin put the parts on the car. It's our Stage 3 package here at Cobb. We've got a map ready to go for that. So I was able to just flash it on the car. This particular map isn't made to have flex fuel on it. So right now I've got the flex fuel kit disabled. With flex fuel, the whole point is you can run gas, E85, any mix of the two, and it'll work regardless. So it's not that we're not using flex fuel because you can't. It's just that we want to show what the off the shelf map can do before we get into custom tuning. So let's run it and see what happens. All right, here we go. Looks like about what I expected. Now lumps and bumps. Let me take a look at the log. We're hitting our boost targets. Air fuel ratio looks good. We've got no knock. Everything looks good. So that's what we like to see. Awesome. And now like we did on the baseline, so we're going to do a few more pulls just to back it up. And that way we can take an average later and just make sure everything's nice and consistent. All right. Right, so looking at those two runs, it looks like they laid pretty much right on top of each other. Consistency is one of the main things we want to see. I am ready to do our third pull. Yeah, it looks like all three runs right about the same. That's as good as it's going to get. OK, so now that we have the modified results, what are the gains from our stop pulls? Well, it looks like we picked up about 20% horsepower and actually about 35% torque. So we had really nice gains for pump gas. And right now we're going to start getting some 85 in the car. And after that, we're probably going to see even more. Very cool. Sweet. So let's get out of the car and start putting a new fuel in. All right. All right, Mike, tell us what's going on here. All right. So we just trained some of our 93 octane pump gas out of the car. And we're getting ready to put the 85 fuel in. Cool. So a lot of our customers here at Cobb have some misconceptions about the 85. So clear up some of that for our customers. Sure, absolutely. So one of the things people are a little unclear on with FlexFuel is what can they run in the car? Can I run pump gas? Can I run the 85? Can I mix the two? Fortunately, all of those are correct. You can do all of those things. You don't have to hit a specific blend of the two. And that's what makes it so easy. So why did we drain the tank of the 93? Yeah, so normally that's not something you would have to do when you're out on the road. The reason we've done it here today is, on the dyno, we want to demonstrate the full potential of the 85 fuel. So by draining the pump gas out, now we can add as much E85 as possible, get the ethanol content as high as we can, and then we'll see our maximum power gain. OK, so we're doing this for the dyno. But how does this translate when I'm just going to the gas station to put some E85 in it? Sure, yeah. And that's going to be your normal day-to-day scenario. So that's what we'll be doing most of the time. In that case, it doesn't matter how much fuel is in the car at the time. You can fill it up. You can fill it halfway, whatever you've got to do. And the flex fuel system is going to calculate how much ethanol percentage is in the fuel right now. And it's going to adapt accordingly. So while you may not get the full power potential of just straight E85, you're always going to get a gain when you have more than that 10% ethanol that you get from the 93 octane pump gas. And you're still going to see a gain. All right, let's get this E85 in there and get back in the car and tune it up. Let's do it. All right, so now that we have that E85 in the car, what's next? All right, so we're going to load up a tune, which is a custom tune made for flex fuel. Then we're going to start the car. And we're going to let the ethanol start to cycle through and see where the ethanol content settles. So I've already flashed the car. We're ready to start it. So I'm going to do that. And then if you look here on the access port, what we're going to see is the ethanol start to rise. And we're just going to let it stabilize a little bit. Take a look at some of the readings I'm getting here. See how the car is running. Everything is looking good so far. And it looks like we're going to end up with an ethanol content of right about 82%. So that's plenty for us to see full power. OK, so is it time to do a pull? Yeah, we've got our map loaded. Things are looking good. Since this is a custom tune, we're definitely going to need to make some changes along the way. But we are ready for a first pull. So let's see how it goes. Let's do it. I don't know if you could tell, but it definitely revs out quicker. That sounds awesome. All right, let's see how much more power we made. Looks like we got a nice bump in performance. That's what we're expecting to see. I'm going to take a look at the data log and see what it can tell me. All right, so in order to take advantage of the 85 fuel, I have turned up the boost. I'm running the air fuel ratio a little bit leaner. I've added some ignition timing advance, made a few other changes as well. And that's where we're going to get some of our gains from. The rest of it is going to come from the properties of the fuel itself. I've bumped the boost up a couple pounds. And it looks like it's liking the extra timing. Let me just take a closer look and see what changes I'm going to make. So right here, what I'm going to do is I see on the higher RPM range, the boost is tapering a little more than I'd like. So I'm going to crank the boost controller up a little bit and give him a little more top end power. Hopefully we can get another couple pounds out of it. And that should net us probably another 10 horsepower. All right, so I'm going to add a little more ignition timing on the top end, which will help with power output as well. Our air fuel ratio actually was spot on on the first pull. And that's because the flex fuel system just does its job, takes care of it, and hit my target. So I'm not even going to touch that. So let's see what these few two weeks do. I'm going to get the car up to speed and we'll do another pull. Cool. Looks like I've got a little more room to go on boost. So I'm going to bump that up a little bit further, especially again at the higher RPM. Try to get as much as we can out of this stock turbo. And a little bit more timing advance. That's always one of the last things that I like to add just for safety. I never wanted to run into detonation during the pull. So we'll just creep that up nice and slowly to be safe. It looks like we're actually reaching the limit of the stock clutch because we made so much torque. The reason I can see that is when we come up to our full boost level, there's a little bit of a wiggle there. And that's where the clutch is just starting to slip. But it's hanging in there pretty good for us. So I'm going to make sure we don't make any more torque, but we'll just keep trying to work on the horsepower on the top end. So at this point, the changes are going to be relatively small. It's going to feel pretty much the same pull-to-pull, but the dyno is going to tell us more in detail where we gained or hopefully didn't lose, but hopefully just where we gained some extra power. So how did everything look? Everything looked great, actually. So I don't have any other changes I want to make. What we're going to do now is our backup run. So we'll call that last one our first. We'll do two more, and then we'll take our average of the three, and then we'll see what we gained. Awesome. OK. Actually, it looks a little bit better, probably because we let it cool down a little bit. Nice. So yeah, I mean, everything's good. Let's get that third pull done so we can get our average. Awesome. Looks like we got another good one. Looking over the data log, I can see that the clutch did definitely slip that time. Probably because we didn't let it cool down as much. What I'll do before the car comes off the dyno is I'm going to back the boost down a little bit. That way we don't just kind of put the clutch over the edge and finish it off. But that's what happens when we do our job well, right? We make too much power. Clutch just can't handle it. So, Mike, what are the results? I want to know everything. All right. Well, so as you remember, we did our baseline first. Then all the parts went on, and we ran the car on the stage three off the shelf map on 93 octane pump gas. Our gains on that setup were about 20% horsepower, 35 torque, which was a lot, but we knew there was going to be more. So we put E85 in the car. We did our custom tune on E85 with flex fuel. And we gained another 12% horsepower and 18% torque. That sounds pretty good, but when you think about it from where we started to where we finished from stock, we gained 34% horsepower and 60% torque, which was so much that the clutch could barely take in. Wow. I mean, that is a lot of gains going on. And it's really cool because throughout this series, we've talked about these components and systems. It's really cool to see how it all comes together, going from stock to where we're at now. And that's just really cool. So now you guys are going to let me take it for a joy ride? Absolutely. Let's go have some fun. Yes. Thank you so much for doing this for us. Thank you for having me. Yeah. And with that, we wrap up this episode and the Cobb U series. We hope that you've enjoyed the episodes and gained valuable information to use when modifying your own car. Thanks for joining us, and be sure to subscribe to our YouTube channel if you haven't already. I'm Emmy, your host for Cobb U. Remember, check out Cobbtuning.com for all your parts and tuning needs. Do you like the storage solutions featured in our studio? Then visit sonictoolsusa.com to get more detailed product information.