D20 I5: The cutted-off D24

[Intercooler-BurnzZ]

Hi there!
I am wondering if someone knows about the "mostly unknown" D20 engine which was specially designed for the Italian market due to cheaper tax for engines <2000 ccm. Any idea how many vehicles has been equipped/delivered? I hardly find anything about this engine. Must have been really unpopular, the 240 diesel with 79/82 hp without turbo was already really slow, but the cut-off engine must be a real snail.
Best regs,
Bernd

[v8volvo]

They were never sold here (US). I have heard the same thing you said, that they were intended to be sold for use as taxis in particular countries where tax rules favored the smaller displacement. The same engine did come here in Audi cars (5000 or 100) and I believe had around 65 hp. It would be very weak in a heavier Volvo but maybe with very short gearing for city taxi use it would be OK. Highway or hills would be tough. With the lack of power I doubt the economy would have been any better either. Presumably they were produced in fairly small numbers and probably all of them got used up and thrown away since they would not have been attractive for any other purpose. There are probably few or none still existing. The service literature does include some info on them but even there it is limited, almost reluctant. Volvo could not have been particularly proud of it as a product and probably only offered it as a way to get a slice of those tax-break markets.

The one thing that could be beneficial about one now is that the old 2.0 5 cylinder engine shares external dimensions with later Audi 5 cylinder engines which include a 2.5L TDI (as well as some high performance twincam gas versions). It would be fun to get hands on the oil pan/pickup tube and the engine mount brackets from a D20 since they would presumably allow you to bolt the 2.5 directly into a 240 engine bay. The 2.5 TDI would be a great engine to have in one of these cars given their power and economy. The loss of the 6-cylinder smoothness and sound would be the only disadvantage relative to the D24T.

It's a shame VW/Audi stopped developing the D24 family in the early '90s during when it was revamping the 4 and 5 cylinder versions of the engine for electronic control and direct injection plus a block deck height and stroke increase for greater displacement. The old 1.6D became 1.9TDI, and the 5cyl 2.0D/D20 became 2.5TDI that had up to 140hp right out of the factory. If there had been an equivalent 6-cylinder version developed from the D24 it would have been a 3.0L TDI inline six with around 170hp stock and enormous potential beyond that. The 1.9 is capable of 160-170hp and 300 lb-ft with very little effort so a similar 3.0L 6-cylinder would probably have been approaching 250hp and 450 lb-ft with the same minimal changes, or far more with internal work. Fun to imagine.

Have to assume the reason it didn't happen was because VW and Audi were no longer producing any vehicle platforms with room to use an inline six engine by that time, and Volvo was ramping down production of its RWD models in the mid '90s so the engine would soon have been orphaned with no applications. The increased power of the 5-cylinder version may have been considered sufficient to cover any existing D24 applications anyway.

Still it's interesting to see how easily it might have been done, since the combustion and airflow engineering was all already in place for the smaller engines in the same family and all it would have taken to manufacture a 6cyl version was a little more block material, a cheaper-to-make DI head without prechambers, and one more piston of the type they were already producing. If they had done this and offered it in the late 960 cars it would have been a great setup.

Anyway, back to your question about the D20, to my knowledge we have never seen anyone show up here owning one or having ever dealt with one firsthand.