Hello
I'm thinking of swopping the engine in my S3 next year. It's a petrol 2.25 and I need something alot more economical. Anyone know the most suitable replacement (minimum work as I'll have to pay a mechanic
) but wanted something a bit more upto date than the 2.25 diesel. Any ideas?
A 200Tdi is likely the easiest swap all things considering, you can retain your current gearbox and transfer case and just swap the engine over.
Economy wise, well it depends, driven carefully a Tdi can see over 30mpg, but I'd budget more like 25-28 as the norm, especially with the 4 speed gearbox and low cruising rpms.
You can go further and fit a 5 speed box and LT230 transfer box, but the amount of work will suddenly increase quite a bit.
As for being up to date, well I guess that's how you look at. The Tdi is sort of modern, but it's still very much old school, in fact the actual block and crank hail from the original 2.25 petrol motor.
So while a Tdi is a step up in power and economy, it will likely be more noisy and not as smooth.
Fitting the Tdi 200 is fairly easy, a 300 is possible but requires a bit more work.
Some remove the turbo from a Tdi and fit it, I can't really see the point in this unless there is a legal reason to do it (some European countries). There's enough room to make it all fit, although if you want to retain the Series front panel there isn't a lot of room for the intercooler. An electric fan rather than viscous and a bit of creative plumbing can get it all to fit though. Or your other option is to convert to a Defender style front panel as it'll give you 8-10" more room.
Other drop in engines would be the Rover V8. Certainly more up to date power wise, but not great on fuel. Running LPG would be an option though and pence per mile wise would be very similar to running a Tdi.
Rover T Series is probably the most "modern" engine to drop in. A 2.0 litre DOHC engine. The make more power than a Tdi, but lack the low down torque. That said, they are probably more economical than a V8 or a 2.25
There is also the possibility of running the 2.0 turbo variant with a little custom work. It won't be great on fuel, but would be a massive improvement in power and a marginal improvement in mpg over a 2.25P.
Lots of other engine options exist, Perkins diesels were common swaps at one time and more than a few Peugeot diesels have made their way under Series bonnets too. Ford Essex and Cologne V6's are Rover V8 alternatives.
But the more obscurer you get, the more custom work and R&D you'll have to do to get it to work.
