Seat Leon Cupra & LPG - groover
Hi - I own a 2002 Seat Leon Cupra and love it to bits! The only problem is that I\'ve just changed jobs and am commuting about 300 miles a week, and the fuel costs are starting to cause a bit of a dent!

Apparently, the Cupra 1.8 20VT engine has just been approved for LPG conversion. It would cost me about £1300 to covert.

I was interested - BUT Seat informed me that if I had LPG fitted it would invalidate their 3 year mechanical warranty.

So, I have 3 options:
1) Covert to LPG and gamble that nothing major goes wrong with the engine.
2) Sell the Cupra and go for the Diesel Leon.
3) Stop drinking so much beer and carry on running on petrol.

Any thoughts please?

Seat Leon Cupra & LPG - andymc {P}
I have a diesel Leon - like you, I love it to bits! I have to admit to preferring the way modern diesels drive to petrol, so I don't know if you'll find the different characteristics of a diesel to be better or worse than your experience. Still, I must say that even with just 110 bhp the car is as fast as I need it to be, and more importantly is flexible - I can overtake uphill in fifth, even HGV's, with no worries at all. Plenty of power low down in the rev band.

I also do a similar commuting distance to you on a mix of A roads, B roads and m-way/dual. The car handles brilliantly, and I think the TDi SE has the same brakes and suspension set up as the 180 bhp Cupra (think your Cupra R has uprated brakes).

The torque figure for the 110 bhp TDi SE is 173lb/ft at 1900 revs, which is actually a bit better than the 180 bhp Cupra torque of 173 lb/ft at 1950, but not as good as the Cupra R's 199 lb/ft at 2100 revs. Ultimately, the trade-off will probably be worth it for greater flexibility and less frenzied commuting. Oh, and the engine will sound different!

In terms of economy, I usually get mid-fifties mpg without trying, and that means a usual full cruising speed on motorways and a fair bit of overtaking on As and Bs (obviously I never break the limit ...). During my first year with the car I was at the stage of watching what the mpg was like and tended to get around 650 miles from the 55 litre tank, and have managed a couple of times to get a bit more than 700. Not that I'm recommending you do that - why buy a car you can have fun with then deny yourself the fun? Especially considering that once it's three years old, you can chip the TDi to 147 bhp without worrying about warranties, but still have the economy of a diesel in the meantime. For comparison, the 150 bhp Golf PD has 236lb/ft at 1900 revs, so I'd guess you wouldn't be too far away from that with a chip.

Looking at the LPG option, you're right about the manufacturer's warranty, but I think that approved installers should provide a warranty for any parts affected by the conversion. Best to check with an approved installer, approved being the key word here. If you go into London every day, the saving on the congestion charge would almost pay for the conversion in a year. But I'd guess that LPG won't give you the kind of performance you'd expect from the Cupra, and it might be harder to sell the car later - not a problem with the TDi. LPG is much cheaper per litre, but IMO its relatively low mpg doesn't really give it a huge overall cost per mile saving against a diesel as frugal as the Leon.

Value my car