"Olly R" <email@example.com> wrote in message
> Hello all, and happy bank holiday monday.
> Until a year or so ago, I drove a Stage One V8 109 (on LPG) that I loved
> bits, but had to sell it. I'm soon going to be in the market for a
> replacement Land Rover (hooray!) and whilst my head tells me that I should
> really be looking for a sensible Tdi-engined vehicle, I'm not sure that
> be able to resist the lure of the V8.
> Having had some not terribly good experiences with a carbed 3.5 on LPG
> (maybe I was unlucky), I was wondering about the injected V8s. So the
> questions are
> Is the 3.9 V8i a much better engine?
The basic engine is the same, just a larger bore, it's the EFI system that
makes it so much nicer.
> Does is get usefully better mpg?
About 1 or 2mpg.
> Are there issues with running the injected engine mostly on LPG?
Nope, none at all. Just don't adjust the timing too far advanced, I've
replaced 2 sets of pistons recently that have been destroyed by knock. (Ring
> If I bought a landy with a different engine, with a view to replacing that
> engine with a V8, are there any particularly suitable/unsuitable donor
> vehicles? I'm really after a LWB station wagon.
It's a lot less heartache to get a V8 model with a clapped engine then fit a
decent 3.9 and convert the vehicle to EFI (Fuel pump, fuel lines, wiring
> Presumably the 3.9 needs a catalytic converter, and therefore a
> gas system, all of which is more expensive to install?
Doesn't need cats if pre-92 (I think?) and it won't need them for an MOT
anyway if it's running on gas. Construction and use regs will probably say
you should have them, but I wouldn't worry about that myself.
Something else to consider, from the mot manual I believe, "if the engine
has been replaced, the emissions test applicable is for the engine's age,
not the vehicle's, unless the engine is newer in which case it is by the
vehicle age". In other words, if you rebuild and fit a 1991 3.9 to a 2001
defender, no cats required and no cat emissions test - even on petrol! All
you need to be able to do is provide some sort of evidence of the true age
of the replacement engine, easily done from the engine number.
> So maybe if all this will cost loads, is it on balance best to stick with
> carbs, and hope I get a good 'un?
EFI is a lot smoother, better emissions, and has an easier and smoother
changeover from petrol to gas and back to petrol.
> Any thoughts would be gratefully received.
Go for it, you know you want that burble!!!
Rover V8 engine specialists.