Interchangeable 4.2 ngines

[boomer3]

Hi guys, i've been searching for a bit tonight interchangeability of 4.2 engines and haven't found much other than: http://www.audizine.com/forum/showth...4-2-aka-A8-4-2.

Do we have a definitive list of chain driven 40v 4.2's that can be swapped into our b6/b7 s4's?? I would like to know what other chassis' a 4.2 longblock can be pulled from and still plug & play.

[MidwestB6]

Here's some reading material>>>http://audirevolution.net/forum/index.php?topic=487.0

I wouldn't say any Audi engine can be called 'plug & play', any engine swap involving complex electrical systems are going to have some issues. Depending on your reasoning for doing a swap, you have tons of options. If you want to stick to the MPI 4.2, then the only sensible options are to send it to JHM or find another B6/B7 S4. Using an FSI engine is going to get very expensive, so you'd probably better off with the JHM option. An A6 or A8 4.2 could be swapped in, but you're going to run into little issues that make it a hassle, and end up with less power. Conclusion, any of these swaps could be done(as well as 4,5,6 etc. cylinder engines, but that's another topic) , but the only sensible thing would be to find another BHF or send to JHM.

Biggest thing is, why are you considering a swap?

[boomer3]

You have basically answered the questions that I had. My reason for asking the question is to know what longblocks can directly drop in while still using the s4 intake and wiring etc, (IE no custom work). So I had thought that the A6 and A8 block+heads could potentially be interchanged even if they weren't a BHF.

I have no intention of swapping another engine to achieve higher power or any other function; just simply thinking that in event that I stumble across a great deal on an S4 with a blown engine or head, I would like to be able to open up my engine search to the widest search field possible!

[vacsimile]

Just know that this engine never appeared in A8's, as they went directly from the belt-driven MPI engine to the chain-driven FSI engine. Well, here in the states anyway... Not sure about Canada or anywhere else. B6/B7 S4's, C5 Allroads, and C6 A6's were the only cars to get this engine.

[boomer3]

After continuing to read more, I am starting to come to the conclusion that you can only pull a BHF replacement motor from a B6/B7 S4. Nobody seems to be convinced that the BHF or anything similar enough for direct swap can be pulled from any other vehicle. I'm surprised!

[Kookie]

A6 4.2 SHORT block can be utilized. Obviously a little bit of work is required to mate it up, but nothing too crazy.

[S4orgy]

Can the b6 s4s use the 4.2 out of the 2nd gen s6?if so could the jhm supercharger work with it. Supposedly the internals in that engine can handle more power than the b6/b7 engines

[Guitarmageddon]

Id consider donating a left nut to science if someone put a v10 from an s6 in here....

[gcoy]

Holy !@#$% ^^^You Crazy^^^

[thomasskull666]

I'd donate my right nut so we could make a man to drive that crazy contraption

[Kookie]

Can the b6 s4s use the 4.2 out of the 2nd gen s6?if so could the jhm supercharger work with it. Supposedly the internals in that engine can handle more power than the b6/b7 engines

No, the ANK/AQJ engine is fairly different. Similar in a lot of it's general design ie. (chain driven cams, 4.2 liters, 5 valves/cylinder etc.) but too different for it to work.

[S4orgy]

Or better yet could we use the pistons and rods of let of the 2nd gen s6/or rs4?