Unleaded Petrol.

Hi,

Is the Cylinder Head on a 1984 109 FFR modified for Unleaded Petrol. I am driving it on LPG most of the time.

Regards.

Chris.

In a word no. The only Land Rover 4 cylinder petrol engines that were made for unleaded were the 2.5 engines fitted in 90 and 110. Even the early 2.3 petrol engines in 90 and 110 were unsuitable for unleaded. You're might have been converted since leaving the factory of course.

Is there any way of telling and would running it on LPG make any difference ?.

LPG is worse than running on UNLEADED for an engine designed for leaded only operation AFAIK.

Depending on the mileage of your engine it would have a certain of lead left on it from years of use, often called lead memory. You could just continue to use the engine as is and keep check on the tappet clearances, if your not thrashing it or going for long motorway journeys then it could last a long time, put a few bob away each week to buy a new unleaded head when the time comes. From what I know unleaded heads are painted black but I could paint mine black tonight but it wouldn't make it unleaded if you get my drift.

Its ex British Army, so am pretty sure it would have been well looked after, I hope. I only use it at the weekends and cover about 100 miles at most each run. There is 76K miles on the clock but would have only about 1K miles approx on LPG. Overhauled the head about 6 years ago and have not had to adjust the Tappets since. Starts first turn and runs like clockwork.

When did it leave the army? Unleaded was introduced in 1988 I believe, so they may well have put hardened valve seats in.
Had it done on my 2.25 engine and never looked back

Not sure. Is there any way I can check.

Personally I would not go to the expense of unleaded seats unless they were seriously recessed and affecting performance, and I couldn't find another good head economically. When unleaded seat replacement first kicked off many years ago I had a cylinder head for a triumph bonneville done (along with new valves and guides) at great expense, wish I had not bothered after one of the seats fell out and wrecked the top end. And that was done by one of the well respected gurus at the time. I can still find old heads with excellent condition valve seats and look for those whenever I need one, as I can get one cheaper than having unleaded conversions. Also if I was getting unleaded seats I would just do the exhaust seats as the inlets run cooler with the intake of cool air / petrol mix. With unleaded fuel you might need to retard the ignition a degree or two if the engine pinks, modern unleaded seems to be a bit more volatile than the old four star.

Thanks for that. I had the same problem with a 1964 3TA. 109 is running like a clock, so will take your advice and leave well enough alone.

Fully agree, don't fix what's not broke! There's no advantage
I was fortunate and got a good job done at a very reasonable price by a retired guy with all the right tools in his garden shed