Lindward

is the 4.2 engine in our cars the same as the 8 in the Toureg??

qfrog Ti20

the shortened V8 in the B6/7 and AR&C6 does not have a front timing belt, it has a rear timing chain like some other new V6 and V8 engines.... actually the new 2.5 I5 is rear chain drive too... much like the VR and W engines are... this dates back to about 1991 with the introduction of the VR6. Timing belts are being phased out for better or worse.

what I'm trying to convey is that they are not the same engine they will have some simmilarities as do all audi engines... after working with them for some years now audi engines seem *normal* to me. The V8's are from two different generations of engine. The belt drive block I believe is largely is evoloved from the 3.6 PT code V8 from the late 80's... however the cylinder heads are no longer 4v but 5v. IIRC the 4v cyl heads were related to the VW 16v cyl heads of the MKII GTI. The 5v cyl heads are not really related to the 4cyl engine since they use roller rockers which I dont think the 4v engine had. The newest engines seem to have not just cam bearing caps but a single girdle that retains both cams across the entire bank. These are just a few of the ways in which the engines have evolved over the years.

Just because its an audi 4.2 does not mean its the same engine. There are probably more than two dozen different audi 4.2 engine codes, each one a slightly different motor with an intended purpose . Ranging from 240hp 3.7 fwd A8 to 450 bi-turbo RS6 2003 or even more the RS6 plus engine.

Even today the most updated 4.2's are FSI, which goes back to a 16v cyl head architecture, however space must be made to seat the injector where a valve once was with the 20v head architecture from the 5v engines.

I can see 4 distinct generations of audi V8 engines.

1 4v belt
2. 5v belt
3. 5v chain
4. 4v FSI chain