Is it really so hard to do that? I mean the wiring.

 

It's a piece of cake if you know what you're doing, if this is your first time prepare for a ton of frustration. I spent hours on hours studying the diagrams before I even bought anything, but that was DBW to DBC, what you're doing will be a good deal easier because you don't have to make a pedal harness. You will lose cruise control unless you figure out how to connect the controller and vacuum pump though.

 

well, this is my first time doing such a big job. before this I had honda civic and had to swap the engine, but it was all the same. This job on the other hand involves more things to be done. I believe that I will have to swap the speedo also because they differ. I believe I will have to post some photos, so it would be easier for You guys to see and understand the things I am talking about. I guess it would help you to give me better advices also.

 

Who needs cruise control anyway lol. Just another way to fall asleep behind the wheel.

 

both of these cars don't have a cruise control. I was wondering - do I have to change the drive-shafts also. how will the ecu from 1998 accept all of the rest things on my 2000 car, like abs, airbags and other components, will it need reprogramming?

 

Dude you need the engine, engine bay wiring harness, all the engine accessories, the gas pedal assembly (for the drive by wire setup), and probably a bunch more stuff. It's not as easy as "yank engine A, drop in engine B".

 

If I was to swap anything into my B5 eventually, it would be a V8 40v. I need to save like 5 thousand dollars to even get started on a project like that. I know some guys on this forum have fabricated or have access to exact specification parts that are needed to do the swap so finding original parts isn't necessary, although I assume original parts are the best. I need to go to a couple junkyards and look for a 40v. You never know, might get lucky. Swapping the engine in is pretty straight forward from what I read, as long as you have the custom mounts needed. The hard part is wiring the engine back up.

I also wondered, is a A4 2.8l instrument cluster theoretically compatible with the wiring harness of a 4.2 40v? I know some gauges may be missing but I read somewhere that the A6 or A8 clusters don't fit.

I am assuming that I would have to throw the ECU from the V8 into the car and take the current one that I have out?

 

For the V8, yes the ECU must be swapped - cant run a V8 on a V6 computer. The A4 cluster won't work as it can only take pulses from 4 and 6 cylinder engines. A C5 A6 cluster can be swapped in for use though - that car offered the 4.2L engine and the cluster fits nicely in the A4. Follow the active V8 swap thread that member bshusted is writing for all the things he's learning and sharing.

 

Which motor would work better with the C5 A6 cluster? The original 4.2, or that newer 4.2 V8?

 

Far as I know it won't matter. What matters is having a cluster that can take V8 ECU pulses.