| The VW and Audi TDi diesel vehicles are | | | | of the TDi's that will increase airflow |
| probably the most economical cars on the | | | | slightly, and add a little power and economy. |
| road, getting about the same or better | | | | |
| economy than the new hybrids. They are the | | | | The next thing that comes to peoples minds is |
| best way to go when looking to save money on | | | | an upgraded exhaust system for their TDi. The |
| fuel. The VW TDi's especially are growing in | | | | only problem with that is the lack of mods |
| popularity in the U.S.. There are some | | | | for the TDi exhaust. There are currently no |
| complaints though. Like not having the power | | | | major companies that manufacture full TDi |
| needed to pass someone on the road. This has | | | | exhaust systems to my knowledge. A custom |
| all changed in recent years. There are | | | | system can be made, but often cost in excess |
| several upgrades that can be made to the | | | | of $750. So most people do either 1) A |
| TDi's to improve power, and to actually | | | | mufflerectomy where the muffler and resonator |
| improve fuel economy even more. I will touch | | | | are removed and straight pipes are put in |
| on these subjects briefly. | | | | their place to reduce restrictions on exhaust |
| | | | air flow. This doesn't really give a |
| The first TDi Performance mod that comes to | | | | measurable power or economy increase, but |
| mind is an upgraded chip or tuning box. Both | | | | does give a throatier sound that some are |
| of these items, the VW performance chip and | | | | looking for and the reduced back pressure |
| the VW tuning box change how the fuel is | | | | will add to engine longevity. Or 2) People |
| delivered to the engine. For a VW performance | | | | will replace the muffler with a new muffler |
| chip to be installed, the TDi's computer must | | | | that is able to vacuum the exhaust out the |
| be removed and sent to someone who can solder | | | | tail pipe. These mufflers will add a little |
| in the new chip with the new program. A VW | | | | performance and economy, although still not |
| tuning box will simply be connected under the | | | | very noticeable, but they will greatly reduce |
| hood where it can intercept the signals going | | | | back pressure to add to the longevity of the |
| to the engines ecu and alter them. Most | | | | engine and will also add a deeper tone that |
| people will say that the upgraded chip will | | | | some are looking for. |
| do the most for you, but the tuning box is | | | | |
| the more common upgrade just because it is so | | | | Another common upgrade for the VW TDi is |
| much easier to work with. Also the tuning | | | | upgraded injector nozzles. Upgraded injectors |
| boxes are well liked because they can be | | | | or injector nozzles and an improved spray |
| removed and have no trace of ever being there | | | | pattern than the stock injectors and when |
| so that warranty work can be done. | | | | required are able to flow more fuel. They |
| | | | greatly add to performance and add a little |
| The TDi Performance upgrade that comes to | | | | economy too. They are also an inexpensive |
| most peoples minds first is the cold air | | | | upgrade, and high on the bang for your buck |
| intake. An upgraded cold air intake in a VW | | | | scale. |
| TDi will add approximately and additional | | | | |
| 5-10% increase in power and economy. It is | | | | There are also other things such as propane |
| able to accomplish this by 1) Flowing more | | | | injection or water methanol injection that |
| air which helps the fuel to combust more | | | | will add power and economy but I won't go |
| completely, and 2) Cold air intakes are | | | | into detail as they are not common mods for |
| sealed away from the hot engine air. Cold air | | | | the TDi's. Also with any modifications, a set |
| takes up less space, so in turn more air is | | | | of gauges should be added to monitor the VW |
| able to occupy the same area because it is | | | | TDi's engine parameters and to make sure that |
| cold and not hot. That is a pretty good jump | | | | things are functioning properly. |
| and the cost for the upgraded air intake is | | | | |
| minimal. One of the drawbacks is that | | | | Nathan Young is owner and operator of |
| upgraded air intakes are not available for | | | | Parley's Diesel Performance, and is a |
| all of the TDi models or year groups. There | | | | |
| are also performance drop-in filters for most | | | | TDi Performance enthusiast. |