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Practical Reflash Tuning: Step 1: Download Existing ROM

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Step 1: Download Existing ROM


00:00 - The first step of our 6 step process is to download and save the existing ROM file out of the engine control module.
00:07 We're doing this so that we've got a saved version of the calibration that the engine was running on when we first started and this way we're going to be modifying a copy of that and if anything goes wrong as we go through our tuning process, maybe we make some modifications that we're not happy with the results from or alternatively we just lose our way during the tuning process, we've always got that base ROM file that we can revert to that's a known good quantity.
00:35 It's also useful because we can use that base ROM file as a compare file and this will allow us to see where we've made changes between the 2 files and copy across the specific maps or parameters that we think we made a mistake with or something similar and we'll actually see, we go through this process as we go through this particular worked example.
00:58 The particular car we're dealing with here already has a modified ROM in it.
01:03 We've made some modifications to the existing calibration to suit the over the radiator intake, the headers and the exhaust system.
01:10 And this is an area where you do need to make some decisions.
01:14 Particularly if you've got a car that's an unknown quantity that's come to you and it's been tuned elsewhere, often it can actually be a better option to revert to a completely stock calibration with no modifications at all.
01:28 This is because the majority of tuners will make modifications that may not quite be correct and you can be working from a tune that has some baked in errors.
01:38 In our case the existing calibration that we've got in here is suited to the modifications we've gone through our own 6 step process so we're confident that this is a sound starting point.
01:47 The reality however with the range of modifications we're making, it's not going to be left very close to what we've got now anyway and you'll see that as we progress.
01:55 So let's jump into our VCM Editor software and what we want to do is click the little read vehicle icon in the top tool bar.
02:04 That'll bring up our vehicle reader box which we can see here.
02:07 What we want to do now is make sure that our vehicle is powered up, we don't want it running, we don't want the engine started, we just want it in the run position and of course we want our usual precautions, making sure that our laptop and our vehicle battery are in good condition.
02:20 We can now click on the read button and that will read from the vehicle.
02:26 This is a process that does take a little bit of time so we'll just allow that to go through now, it's going to take in this case about 2 minutes and 30 so we'll speed up this process.
02:34 Alright our read's complete there and we can turn the ignition off.
02:38 I should have also mentioned here that there are actually 2 controllers in our particular vehicle and the VCM editor software will do a complete read from both of them.
02:46 We've got our engine control module which is an E38 engine controller and we've also got a 6 speed automatic transmission which has its own separate transmission control module.
02:55 So the VCM Editor will take a read out of both of those so it's about 2.5 minutes for the engine controller and around about another 1.5 minutes for the transmission controller.
03:04 Right now we can see that we've got this save as box popped up which has allowed us to give the file a name.
03:11 We'll go into that in a second but it is just worth mentioning here that if you haven't previously applied some licenses to this vehicle you will need to license the file before you can tune it.
03:22 So you will typically need, in this case, 2 credits to actually allow you to tune this.
03:28 This will just be a box that will pop up that will talk you through the process and if you don't license the particular file, you're not going to be able to perform modifications to it, you still will be able to read and inspect the calibration, you just won't be able to make changes to it.
03:43 In our case of course we have already got the vehicle license so we don't need to go any further.
03:48 And we can see I've already got 1 calibration saved in here which is for our stock file.
03:52 You can see the naming criteria that I've used here, in this case we're using the registration which in this vehicle is EZB902.
04:00 I like to add a little bit of information here just so I've got a reference at a later point.
04:05 And this becomes more important once you actually start building up a bit of a library of these tune files so you can go back and reference a particular set of modifications.
04:16 So you can see the one that we've already got saved here is our stock file.
04:18 So this is showroom stock as delivered, always got that to revert back to.
04:22 As I mentioned, the modifications here I just refer to as stage 1 which is our intake and exhaust so that's what I'm going to refer to this as.
04:31 And we can get a little bit more detailed here if you've got injector swaps or you've fitted a supercharger, in our case the cam, we'd put some details around that so again we can reference that at a glance.
04:41 We can now click save and that will save that particular file.
04:46 Now in most instances what I would recommend, as discussed in the course is that straight away, we come back up to our file menu and what we're going to do is click on that and we'll go save as, so I've already got that file opened up and now what we can do is give this another reference at the end which will be something like tuned or modified or a reference again to the modifications that have been performed.
05:10 What this does is it ensures that you've straight away got a second file saved.
05:15 At this point it's exactly the same understandably but then you can work from that tuned or modified file and it's going to leave your base file untouched.
05:24 It can be very easy to forget this step and you end up downloading the existing calibration and start modifying it before you realise and then you've lost that base calibration.
05:35 In our case I'm going to cancel out of this, it's not required because one of our next steps is going to be to perform a speed density patch and that actually requires in and of itself, us to perform a save and give the file a different name.
05:48 So we don't need to do that at this point, we've finished our first step, we've got our base file downloaded, we can move on with the next step of our process.

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