See what our customers have to say about our industry leading software and products.

Joshua M - Sheffield - Custom-Code Phase 1 - BMW M3 E46 + FlashWire

I had the ECU in my old Fabia vRS calibrated by Custom-Code the day after I bought it (brand new) in 2004. The company was new back then, but I had confidence in their abilities as I had been a regular customer of their sister company, JBS, since 1999. The car performed brilliantly for the 3 years and 60k miles that it was in my possession, with incredibly smooth power delivery and a dyno-proven 187bhp and 295lbft.

Fast forward to late 2013 and I'd moved away from the VAG scene and now own a 2003 BMW E46 M3 SMG. I'd read various reports on the forums that the M3 responds well to ECU calibration, but none of the companies were local to me. When I learned that Custom-Code were launching their BMW calibration range to the public, I jumped at the chance to try it out! Part of the special launch offer was that the FlashWire remote flashing tool was included, so even though I am fairly local to their head office, I decided to try this too.

The bundle includes a special OBD-II cable and an 8GB USB Memory Stick containing the FlashWire software (for Windows) which also installs the drivers for the cable. An added bonus was the box that it all comes in looks really professional and is a great place to store the cable for future use!

Once I installed the software and driver, fired up the software and connected the cable to the car, the cable was locked to my ECU/VIN during initialisation, obviously to prevent its use on multiple cars.

I performed both full (512k) and partial (32k) reads of my ECU, then emailed the files across to Custom-Code for calibration. They then called me and asked me whether I wanted a standard Phase One calibration, or if I wanted to upgrade with any options and if so, what fuel I used; to which I replied that I'd like Sport Mode memory, Dyno Mode enabled, Speed Limiter (VMax) removed and that I always use Shell V-Power Nitro+ fuel. I was told that this would put it somewhere between a Phase One and Phase Two calibration; I don't have any hardware mods, so it won't give the same benefits as a proper Phase Two calibration, but as I always use high-octaine fuel, they could eek out some more power.

Within a few hours, I received an email containing an encrypted calibration file which I flashed back to my car using the same software... All very straightforward and pretty-much idiot-proof!

Over the next few days, I spent quite a lot of time in the car, driving on everything from twisty damp B-roads to a motorway and I can safely say that Custom-Code has made a significant improvement in the way the car drives.

It's faster... My wife even noticed it as a passenger. I haven't done any before/after dyno runs, but it feels much stronger. C-C quoted around a 25bhp increase, but for me the major improvement has been the increase in low down torque which has made it feel faster in "normal" use (not just when nailing it!).

It's smoother... It's hard to explain, but as standard it felt like the torque came in steps, but now it's more of a smooth wave. It's got rid of an annoying flat spot that had been bothering me since I got the car.The car is also now a bit louder too! I wasn't expecting that, as no hardware has changed, but it now sounds a bit more "raw", growly and exciting.

I got sport-button memory too which is great. FlashWire also allows me to flash back to my original stock file if necessary (for instance if I take it back to the dealers), as the original file is sent along with the tuned one and I get to keep the cable and software.

It's now been a couple of months since I had this done and I'm still really impressed and recommend it to anyone wanting a simple but really effective upgrade to their E46 M3!

Joshua M - Sheffield

Dan M - Wigton, Cumbria - Custom-Code Phase 1 - Audi A3 2.0 TFSI + FlashWire

Back in 2009 I had Custom-Code map my Audi TT 1.8T. I was so impressed with the map and how the car drove, when looking for a map on my Audi A3 8P 2.0 TFSI 200PS the only place I wanted to map the car was Custom-Code.

Since my last dealing with Custom-Code they have stopped offering mobile mapping, so it was a choice between the 340 mile / 7 hour round trip to visit them, or test their new FlashWire software. After numerous e-mails I decided to give FlashWire a try and below are my thoughts.

The item arrived quickly and very well packaged. Inside the FlashWire box was a nice metal USB flash drive containing the software, the FlashWire cable along with a couple of Custom-Code stickers.

The software was installed within minutes, straight forward following all the default options. First job was to read the ECU, this took around 15mins and again it was very easy, click 'read ECU' on the software and let it do its thing.

This read file was e-mailed to Custom-Code out of hours on a Wednesday night, 9am Thursday morning I had the coded files e-mailed back ready to be uploaded. Again this couldn’t have been easier, open the software and choose 'program ECU'. 10mins later after the programming had finished I knocked off the ignition, turned it back on and was ready to test drive.

The car… well what can I say? WOW & OMG seem to fit quite well. First drive I was grinning from ear to ear. The turbo kicks in much earlier and it keeps pulling all the way to the red line. After driving it like I stole it for the first few days it still impressed me. Taming my driving down for my daily commute it’s still a perfect daily driver, and when driving “normally” it is returning slightly better fuel economy on my commute than pre Custom-Code software.

I went back to Custom-Code for how good I found the TT map, and they didn’t disappoint. I will be using Custom-Code and without a doubt FlashWire again on all my future cars.

Special thanks to Tim who has been brilliant throughout my whole process.

Dan M - Wigton

Ben S - Stoke - Custom-Code Phase 1 - Seat Ibiza 1.4 TSI 180

“I never realised that flashing new ECU software could bring me so much joy! The gains I have received and regularly experience with my Ibiza 6J 1.4 TSI 180PS are incredible. I would recommend Custom-Code software to anyone with a VAG group vehicle, these guys really know what they are doing!”

Ben S - Stoke

Jody L - Milton Keynes - Custom-Code Phase 1 - Audi RS4

I can honestly say that I was more than surprised at the improvement that the Custom-Code remap has given my RS4, I was convinced after using the car daily for just short of a year in standard trim that there was very little that could be done to create an increase in power or drivability from a remap. Short of serious engine upgrades I was nearly sure that any gains would be minor and hard to notice on the road.

Wow, how wrong I was, after receiving the software from James at Custom-Code and him assuring me that I would be pleased with the results I began to get a bit curious, could that peach of a motor get even better?

A bit about my RS4, it’s totally standard and at the time of the remap it had only done 8000 miles, the only grumble I had with the performance was the low down power delivery, sure when it hit 5000 rpm it pulled hard to the red line which is why I was near certain the remap wasn’t going to make much improvement.

As soon as the ECU was flashed it was left to idle and get the oil temperature up, ready for it’s first test. I was secretly hoping that it would be better as I was beginning to lose a bit of interest dare I say in the car and now was the time to find out if James was pulling my leg or not. No sooner had I pulled away the difference was there, it was totally different, I had only accelerated 100 yards to the junction and I could feel straight away the improvement, the throttle response and surge forward from low revs was unbelievable, the revs picked up cleanly and quickly up to the limiter in 1st which is now set at 8500 rpm.

Time to find a decent stretch of road to get an idea of the improvement in the higher revs and gears, and it just gets better and better, the rush that the car used to have at 5000rpm now feels even more defined and the fact that it now revs to 8500rpm is just brilliant, it has made the car a whole lot better for me, on my favourite stretch of road there were a couple of sections where before I’d have to change into 4th where I found it a bit sluggish, as I was really too slow for 4th but too fast for 3rd if you can see where I’m coming from. Now the extra 2500rpm means I can hold 3rd longer which has made that section of road even better, obviously it’s a private road of course.

The power delivery is now way better, it revs higher and pulls harder and provides everything you would hope to get from a remap but rarely do, especially when a car is naturally aspirated. I’ve now covered over 2000 miles with the remap and I’m constantly impressed, I have seen just shy of an indicated 175mph, in 5th gear just on the limiter. I kid you not, the car just keeps going and going.

I have owned a huge range of fast cars (911 Porsche’s, numerous highly tuned VAG 1.8T’s in a range of cars, old shape RS4 to name but a few) and bikes (currently Yamaha R1 and a Ducati 1098s on the road), I work with cars daily ranging from 1.0l Polo’s to RS6’s, so it’s safe to say my opinion and experience counts. The Custom-Code remap is the business.

Jody L - Milton Keynes

Mark B - Sheffield - Custom-Code Phase 1 - VW Golf Mk4 1.8T

As the title suggests, I had my car remapped today by Custom Code. After owning the car for 14 months I decided that it needed a bit more. Don’t get me wrong, 180bhp as standard was plenty quick enough, but I just felt that my Golf and all Golf's leave the factory slightly underpowered and the standard map just held it back and restricted the car from being how a GTI 'should' be.

So after much consideration I decided for a remap, but which one? I researched this for numerous weeks totalling up all the pro's and con's of each company...Jabba, Revo, Custom-Code, etc. I wanted a map that felt how an OEM GTI should feel, i.e. smooth power throughout the entire rev-range, smooth torque, and so on.

I had read about some companies 'spiking' the map so that the turbo pushes out big power down low, but does not carry it all the way to red-line, instead it dies off early. This seemed rather pointless, especially in a FWD car. This kind of map would 'throw you' into your seat, but then die off rather quickly. Don't get me wrong some people may like the feel of this, but that’s not what I wanted to achieve. I was after a map that would 'push' you into your seat, but then hold you there right up to redline.

Bearing all of this in mind, I narrowed my search down to two companies, Custom-Code and Jabbasport, both of which had received nothing but praise, and very similar results on the rolling roads, but which one to choose? After much deliberation, I was swayed towards Custom-Code because of their mobile service, they come out to anywhere in the UK and can even map your car whilst you’re at work, bonus! I rang them up, and they were friendly and helpful, as expected. Then came another major bonus, 30% off the price of all maps! The only dilemma I was left with was which map to choose.

I wanted to keep the Anni as standard as possible, no intercooler change, no cat/exhaust change, just a DV and Intake (easily reversed). So I chose the Custom-Code Phase 1, booked it in and got it done for just over £310. Leigh came out and sorted it, despite running late (due to v.bad traffic), he still arrived on my doorstep way after he should be at home relaxing after a hard day’s work. He was a very friendly bloke, and it was very efficient service, he had the map put and tested it with no problems. I have read numerous reviews regarding how amazing the Custom-Code remap is, but I am very sceptical of the reviews I read and how spending ‘X’ amount on something will 'transform' your car. i.e. a rear ARB, etc. (By the way I have a rear ARB). So I was quite cautious of how good the map could really be.

Bearing in mind it was very wet and raining, I planted my foot, to test the map and was not that impressed, quicker, but quite a bit of wheelspin, exactly what you don’t want on a FWD car. But I took the car home, let it stop raining and dry up a bit, so 2 hours later I tried again. This time I found a straight and open road, with no traffic. I put it into 1st to get moving (no point in flooring it in 1st as it wheels spins in the dry with the 180 map), put it into 2nd (medium revs) then put it into 3rd and floored it, going a bit quicker, then the turbo kicked in!

Amazing, just simply amazing...EXACTLY how a GTI should feel as standard, EXACTLY how VW should make their cars feel, EXACTLY what my car was crying out for and EXACTLY what I was wanting. The car pulls so well all the way through the range in a strong but smooth way, and after hitting redline in 3rd it became very clear that the car was acting more like a V6 rather than a turbo-charged engine. By this I mean it’s smooth, the power is there when you need it (there was a massive improvement in torque), and frightening when you look at the speedo to realise you’re hitting triple digits so quickly without realising it!

Over the past 4 hours I have tried it on A-Roads, B-Roads, M-Way's and residential roads. The car is just as easy to drive at low speeds, so much easier to accelerate in an emergency even if you’re in a too high gear (i.e. 4th @ 30mph), and so much fun on the motorway, overtaking is easier and its always very reassuring to know that you can accelerate so quickly at 70 if someone were to decide to try to change lanes without looking.

I am not someone who will be looking to make my car any faster, as I honestly believed the standard 180 map was quick enough, but with the Custom-Code software, the whole car just feels so much better, and it is honestly like driving a new car. So in summary, on a 1.8T, believe the hype! If you’re thinking about remapping with Custom-Code...do it!

Was it worth the money...YES! Now knowing what the results are like and experiencing the difference, I would honestly have been happy paying double that price. A big thank you to all at Custom-Code for very good customer service and for supplying such amazing software, and a very big thanks to Leigh for all his help.

Mark B - Sheffield

/// What makes Custom-Code Software the best?

Fuel pump

Improved Fuel Economy

With a Custom-Code remap your engine is running more efficiently and therefore you will experience improved fuel economy. With the extra torque you’re also able to change gears lower down the rev range which will return better MPG.

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30 Day satisfaction guarantee

30 Day satisfaction guarantee

Here at Custom-Code we’re so confident that you will love our remaps that we offer a 30 day satisfaction guarantee. That means if you’re not satisfied for what ever reason then we will happily refund you in full within the first 30 days of purchase.

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Audi tuner gold

Award winning technology

It’s not just us that think our ECU software is the industry’s best, Custom-Code has won the prestigious Audi Driver Gold Award for tuning the last 6 years running. 

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Engine Reliability

We perform extensive on-road tests with all our maps to ensure your engine not only reaches its full potential but also that it doesn’t cause any unnecessary wear or damage.

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