Turbo Diesel Owners Club: http://www.tdocuk.com

Direct link to the review: Click here
On Saturday 14th July, myself (Chris) and Jammapic (James) took a trip over to the CRD Technology headquarters to discuss their new Select-A-Map diesel tuning solution.


We were welcomed by Eddie upon arrival, who made us feel welcome with a brew (much needed to help the fuzzy head) before discussing business. So we were all ‘singing from the same hymn sheet’, Eddie ran through the basic operation of a common rail diesel engine, including different types of injectors and injection pressures etc. Eddie has been on the engine tuning front for 20 years so explained the basics behind a diesel remap, and how modern ECUs are increasingly more difficult to crack. This led nicely on to the product which we had gone to look at. The Select-A-Map box…

We established that the best way to get more performance from a car is to remap it. So we’re all agreed on that, there are things the box CANNOT control and that’s that.. Then Eddie discussed the needs of some of his customers who come to get their car remapped by him. Customers like to turn up, cash in hand, and get a remap on the day that “The wife’s out shopping”. Whilst this is brilliant for business, it’s impractical because the customer doesn’t want the wife to know about the remap. Equally, they’re worried about the wife driving the car with the new amount of power. The solution was born originally with the need to control twin fuel systems on petrol cars, being LPG / Petrol. From here, CRD began development on LPG conversions for diesels with the simple aim being to reduce diesel fuel consumption as much as possible and allow the engine to run on an LPG / Diesel mix.

Whilst the box only:
a) modifies rail pressure,
b) and is a removable box
This is where the similarities with a tuning box end – the system can completely remap the operating rail pressure throughout the engine rev / load range..

A generic tuning box, whilst not normally being as crude as a variable resistor, just reduces rail sensor voltage by a factor, thus giving a % gain in rail pressure across the entire voltage range. This is achieved usually by either turning a variable resistor, or by using a series of switches, or in some cases even software. Any of these methods simply allow a different % change in rail pressure, thus giving different “power settings”.

The Select-A-Map gives the user the ability to remotely switch to one of 5 power levels using a remote control key fob. Gimmick you ask? Well once you understand how the power settings are compiled, you can appreciate that this actually has a very useful feature. The 5 power bands are stored as separate 32×32 map files on an EPROM chip. These reference rail pressure output (what the ECU will see from the box) as a % of what it actually is (input from the rail sensor). The beauty of this is that whilst you can intricately change where you want to increase fuel, and leave it the same, you can also do a reduced power map for when the car is lent out, to prevent your pride and joy from being thrashed too hard – or limit low down fueling to save a DPF..

What I found really neat was the 'DPF safe' feature which prevents putting any additional fuel in until the car is on boost – thus allowing it to remain clean and not chuck out any black smoke. We did some road testing of the device on a transit van, and were very Impressed with its performance and driveability. By using the dealer handset we were able to switch maps on the fly. However, using the customer remote key fob only allows map switching with the engine at idle for obvious safety reasons. Maps 4 & 5 can also be controlled by a switch / sensor / button. Feed 12v to the arming wire on the unit and map 4 is selected and you can instantly go from a normal cruising map to a full on fueling map, and if you are using NOS etc, arm that too but more on that in a moment..

The other feature of the box, which is very neat, is its ability to control an LPG/CNG/NOS system. It provides the ability to reduce fueling down to say 70%, and it will inject LPG/CNG to make up the lost power, thus giving a better range on diesel. OK, you’re using two fuels, but given how cheap LPG is, you actually make a saving in the long term. Whilst not directly useful to those looking to save money round town, it offers a great cost saving to commercial drivers doing big mileage and also cleans up the burn

This also doesn’t mean that you have to reduce your fueling with the Select-A-Map to run LPG/CNG/NOS, you can also increase your fueling in addition to injecting any of these supplements and make additional power. For instance, on the day, a 160bhp Insignia CDTI ran a Select-A-Map tune with NOS control and made an additional 60 BHP & 90lbft, up from the stock 164hp we saw it run..

For those interested in NOS control, the box, in our opinion, is second to none of the market. It allows the user to put an input from a NOS ‘arming switch’ which will automatically select the NOS control and increased fueling map to allow control of the NOS solenoid and provide additional fueling. This would be ideal for people who don’t run NOS all the time, and who want to control the injection of it more precisely.
CRD Technology did some testing on quantity of NOS and the power correlation, and discovered they could inject 1/3rd of the quantity of NOS and make the same power if they pulsed the injection of the NOS solenoid, in time with the engine's diesel injectors whilst controlling the nitrous duty cycle (or the 'on' time). This is great as it means, firstly NOS consumption is massively reduced but moreover we can carefully control the NOS map with the box, feeding it in low down to spool up a big turbo or limiting it low down to save the engine’s bottom end.

We were really impressed with the product, and while it might not give the ultimate power gains of a full remap, there’s so much more to it than that. It could be REALLY useful for someone who is running a remap already, but wants finite control over the rail pressure and to control an additional, external source such as NOS / methanol.

The unit is programmed using a hand held device, currently available from CRD Technology (even to non dealers). This communicates with the Select-A-Map box initially when the unit is fitted to the car to detect injector type, maximum rail pressure, maximum calculated load acceleration rate and other parameters. Once the initial setup is completed, 5 identical maps are generated which will allow the vehicle to run as standard. The handheld unit can then change each map to suit where the driver wants more or less power, at 3 different loads, and 5 different rpm ranges.

Mark has worked on creating over 60,000 lines of code which allow seamless operation between the handheld programmer, and the fitted box. This allows a variety of safety features to be built in, for example, maximum fuel pressure differential, maximum acceleration rate, DPF safe fuel pressure (to prevent soot generation low down in the revs) and a host of other features.

Once the unit is set up, the maps can be modified in WinOLS to fine tune where you want differences in the rail pressure. Whilst the unit interpolates data between the 15 programmable points on the hand unit,
WinOLS gives the user the ability to change this to make a more customised map.

Hopefully our visit will be of benefit to the forum through reading this guide, however, any questions can be directed at CRD Technology in the first instance, and to myself and Jammapic in the second instance. I know that Company car users wanting a bit more poke will be interested as it doesn’t require modification of the original ECU, and being a universal mapping device, it can be swapped onto your new company car with only the need for a different cable to connect between it and the fuel rail pressure sensor.

Currently nationwide vendors are being appointed, but the main office in Bolton has a ready supply of these available off the shelf.

Direct link to the review: Click here