RufCTR said:
I will search the archives, but I am curious to know if anyone has ever swapped either a 1.9 I4 or 2.5 V6 TDI engine into an early gas-powered B5 A4.
I've done it. Pretty simple with the right donor - if you can find a B5 Passat its virtually plug n play. If not then its rather a lot of messing about and probably not worth the hassle.
Bear in mind transverse engines aren't bolt-in as the blocks are different, but its possible to fabricate mounts if this is your only option.
You would really need a TDI transmission as well - the ratios on the gas ones are way too short for the TDI - you'd end up with a top speed of 80mph!
Oh, and you'd need to figure out how to get the nozzle restrictor out of the tank as well, otherwise you won't be able to fill it up. I just used a TDI tank for mine, but obviously you won't be able to get that in the US.
I happen to have an early-style A4 TDI cluster (with 4.5K redline) going cheap if you're interested. I can get all the rest of it too (wiring, electronics etc) if you go ahead. Shipping a whole swap might be a little pricey though
I wouldn't recommend the V6 TDI to my worst enemy. Its an absolute dog of an engine - stupidly heavy, over complicated, unreliable and a maintenance nightmare. You can easily get the same output from a 1.9 as the 2.5 can do, but for 200lbs less weight and an extra 10mpg.