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