Having never actually run a 2.1 with 1.9 Digijet injection, , I would
defer to Dennis' experience in this matter. (I was just going from
observation of the substantially larger FI parts on the 2.1.)
Al Brase
Dennis Haynes wrote:

>To get the advantages of the 2.1L cooling system you need upgrade it.
>You will need to upgrade or modify the pipes to the radiator, ad the
>appropriate coolant manifold and get the 2.1L water pump, t-stat
>housing, sensors, oil cooler, etc. The 2.1 also uses a larger throttle
>body and of course a better exhaust.
>
>The 1.9L fuel injection and ignition supports the 2.1 just fine. My seat
>of the pants tells me it actually makes more power as it runs slightly
>richer than the 2.1 system.
>
>Dennis
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