TDi 75/90
- Thread starter Gazbo
- Start date
SnubNose
Member
Hi - We've just bought a 90 and I had the same questions as your good self. The dealers that I asked thought that it had just been chipped! But here is the full story:
The new engine owes its higher power output and torque primarily to a new turbocharger with variable turbine geometry and a boost pressure raised to 2.3 bar (absolute). The new charge-air intercooler, with a distinctly higher efficiency rating, also contributes to the 1.4-litre engine’s higher performance, as does the optimised combustion chamber pattern. The compression ratio has been lowered to 18.0 : 1.
Further detailed work on the engine and its high-pressure fuel injection system has enabled Audi’s engineers to comply with the most stringent emission limits currently valid worldwide.
Examples of their work are the electrically operated exhaust gas recirculation system, which now has an uprated cooling capacity and the shutoff flap in the intake manifold, controlled by the engine operating map, which helps to maintain the optimum combustion mixture. The pump-injector elements have a modified spray angle and increased flow capacity to suit the new operating situation.
There have been detail modifications to the entire pump-injector system. The new Bosch EDC 15 engine management with EOBD (European On-board Diagnosis) and separate pilot injection has injector elements of even higher precision and therefore exerts a positive effect on emission and noise levels.
The larger oil cooler and the new pistons with cooling oilway are a logical consequence of the more extreme temperatures likely to be encountered in this powerful engine. Screening measures on the intake manifold and cylinder block have achieved a distinct improvement in the three-cylinder engine’s acoustic refinement.
Hope this answers your question, there is a bit more info at: http://www.audiworld.com/news/03/111003/content.shtml.
Kind Regards
The new engine owes its higher power output and torque primarily to a new turbocharger with variable turbine geometry and a boost pressure raised to 2.3 bar (absolute). The new charge-air intercooler, with a distinctly higher efficiency rating, also contributes to the 1.4-litre engine’s higher performance, as does the optimised combustion chamber pattern. The compression ratio has been lowered to 18.0 : 1.
Further detailed work on the engine and its high-pressure fuel injection system has enabled Audi’s engineers to comply with the most stringent emission limits currently valid worldwide.
Examples of their work are the electrically operated exhaust gas recirculation system, which now has an uprated cooling capacity and the shutoff flap in the intake manifold, controlled by the engine operating map, which helps to maintain the optimum combustion mixture. The pump-injector elements have a modified spray angle and increased flow capacity to suit the new operating situation.
There have been detail modifications to the entire pump-injector system. The new Bosch EDC 15 engine management with EOBD (European On-board Diagnosis) and separate pilot injection has injector elements of even higher precision and therefore exerts a positive effect on emission and noise levels.
The larger oil cooler and the new pistons with cooling oilway are a logical consequence of the more extreme temperatures likely to be encountered in this powerful engine. Screening measures on the intake manifold and cylinder block have achieved a distinct improvement in the three-cylinder engine’s acoustic refinement.
Hope this answers your question, there is a bit more info at: http://www.audiworld.com/news/03/111003/content.shtml.
Kind Regards
Pompeydave
A2OC Donor
Found this thread on a search as I'm trying to find out if the gearing is different on a 90. Anyone know for sure?