Allard Intake Manifold
Manifold design is a very low priority in a boosted engine, especially if there is going to be a $$$ increase in production. The SDI engine has tuned runners because without a turbo, it needs every extra advantage it can get from the intake. On a turbo engine, it’s cheaper for the manufacturer to just make the cheapest possible intake manifold and crank up the boost a wee bit to compensate for its deficiencies! VW didn’t pay much attention to this item in earlier TDIs. On some recent TDI like the 130PD the intake manifold has a better design. The Passat Manifold is the same design but the inlet pipe is facing other side. This Allard intake manifold is basically a Passat PD manifold with the Allard pipe attached to remove the EGR system. This intake allows for more flexible intercooler mounting/routing options, plus, pipes are shorter, therefore lag is reduced.
Plus the Allard pipe has a much better looks and it should improve the revving and some marginal power gains at high rpms.
Please take a look at the pictures in this link Racing TDI Engine Mods
