Leyland Car Owners -

30 September, 2003

: I will try to guide him with this question in the meantime.

: After some fiddling about with LPG over the years, I have come to the
: following ideals for myself.
: Is he using LPG already?
: What LPG equipment does he envisage?
: 1) The engine needs very little doing to it; in standard trim it has good valves and seats. You'll get very little trouble in that area.
: However, it's always worthwhile getting a good LPG head job done, changing valve seats and valves if necessary. Don't try to economise on the head job, because LPG runs with more heat than petrol, and it is a dry fuel: but there again, so is unleaded petrol so far as the engine is concerned.
: 2) Do not fit chrome piston rings; they won't bed in unless you run the motor on petrol. Use cast iron rings to be sure, but I have no problem with moly rings so far with my motor, which has not used petrol at all.
: 3) Although LPG can run with higher compression, I advocate nothing higher than the standard 9:1 compression ratio. It will give a much more reliable and sweet motor, and it also keeps the combustion heat down.
: 4) There is an LPG camshaft available, but I don't know anybody who has used one. After a bad experience with another camshaft in a much earlier engine, I strongly recommend using the standard camshaft, especially with the standard inlet manifold. The inlet manifold was designed for use with the standard camshaft by the Works, and it took a lot of fiddling to get it right.
: There is a single plenum inlet manifold; Jilden Reichardt has
: Info on that as he uses it with LPG. It opens up the way for alternative camshafts, but you would be heading into the world of experiment, which can be very expensive. Anyway, Jilden is a LPG expert in his own right.
: 5) Pay great attention to detail on assembling. If a good/better
: performance is sought, and you have the dollars to spend, keep it standard and blueprint it. That's what Evan Green did to his rally car, and that was no sluggard around Targa Florio.
: 6) Buy yourself a copy of "Propane Fuel Conversions" by Jay Storer, to get a good idea of what you are dealing with. I don't know if it's been updated, but much of what it says will still be very valid. My copy is copyright 1986.
: 7) A main area of concern with LPG engines is in matters of ignition quality and timing. Do not compromise on quality. Same for plugs - I use Nippon Denso and get good results. Be sure that your distributor is curved for LPG. I suggest maximum advance 30 degrees with idle setting at about 12 - 15 degrees, at full advance by about 2000rpm, and no vacuum advance. Don't use it
: with petrol, though. Visit a recommended distributor specialist if you have any doubts.

: Anyway, that's how I would go about it, and it's what I did. good luck, Phil.

: Mike

Leyland P76 Owners 2005

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LPG engine setup

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