VW TDI Engine/transmission Question

The 020 is really not that strong, so if you're going with a newer turbo diesel I'd be worried about breaking stuff with the torque.  How much hp/torque do you want?

You have 90mm axles, the strongest 020 is form the 16v Scirocco  and it has the bigger 100mm axles and bigger input shaft.

A cable shifted 02a or 02j is what you will want to swap if the 020 isn't enough.

I'd like to keep the current transmission, axles, and whatnot, mostly because they are already there. They also have extremely low miles and work perfectly. I just want to bolt an engine into it and go. My main consideration is availability. 1st gen Rabbit engines are harder to find and relatively expensive, while 90's Jetta/Golf engines are common and cheap. I can get an engine from a 3rd-gen Jetta/Golf for very cheap and they are all over the place, so if that bolts up, then it's probably my best option. I don't particularly care about the engine, but I'd prefer a diesel because I like how they sound and mechanical injection with no ignition system is incredibly simple and reliable.

For a diesel platform I have run the ALH TDI setup for many years with there 5 sp . start in 1998 Beetle up to 2004 Jetta Golf Beetle
Can find them very cheap.

With a tune and all the EGR stuff removed and a good clutch will run for ever. If you go 1998-99 Beetle I got a lot of engine parts and 2 ECMs setup for chip tuning with some great tunes $200
Bob Mann

When we ghettocharged our old 16V Golf/020 transmission, transmission life was between 3 laps and 5 hours.  Three races turbo'ed, 4 transmissions killed.  All had the same failure point.  The ring and pinion separated when the pinion shaft flexed under the power at "13" (waay over 11).  The lower bearing on the pinion is TINY.  At "stock" power, the only failure we ever had was 3rd gear overshifting and the tranny getting stuck in 3rd or the clutch getting coated in oil because VW.

I know the 90mm and 100mm output trannys have the same bolt pattern.  I agree with aventari, go with an 02a out of a Mk3 if at all possible.  You will probably rip the pinion gear right out of an 020 if you get a load of torque.

The last year of the Beetle we ran 30 LB of boost and could get 4 hr and 45 min to 14.5 gal of fuel here is what it looked like from the drivers seat at Thompson the gauge to the bottom right is boost
https://youtu.be/1MnV4tSYnoI

The easiest and most reliable swap you'll do if you're keeping the 020 is a 2.0 8v aka 2.slow.  They're ubiquitous in Mk3 and Mkl4 Jettas and Golfs and will bolt up. It will bolt anywhere the stock 1.7 did, the main difference is the block is 16mm taller than the earlier motors.  It won't mangle your 4 speed too quickly either.

Thats what I would run if I were you and I wanted to be on track racing. If you like being in the pits fixing stuff, then go with the turbo diesel

The VW TDI ALH turbo is one of the most miles on on a engine in world some have 400K +  and still running . There is nothing like it coming off a turn with a TDI all the torque in at 1800 RPM  DRVOLKS

One of the keys to budget/ grassroots Lemons racing is finding a drive line that cheap and abundant/attainable. In our neck of the woods you can find any VW/audi for very little monies and have backup parts cars for spares. We choose to go with a 1.8t because over the years i have accumulated about 4 spares engines ready to drop in at any moments notice.

I don't think others would appreciate coming by after you have "marked" your territory! LOL!