Best (economic) engine for a LWB series hardtop?

[pfillery]

I currently have a 186 red motor in my 109" series 3. The vehicle was originally a 6 cylinder. I'm looking at ways to improve the fuel economy - I use it as a daily driver doing about 90km round trip daily, 5 days a week. About 65km per day is highway driving, so in the interests of economy I sit on about 80km/h which seems to be a comfortable speed for the series without over revving the engine. I know these engines are thirsty, so contemplating putting it on gas while the rebate is around (will cost about $700 net but save half in fuel costs).

My question is whether there is another engine solution that could be done for close to the cost of gas that would be significantly cheaper to run than the 186 yet still give a good running speed without flogging the engine. I would rather go with something that is a bolt in solution to my series 3 gearbox than a full on conversion.

People say the revs of the 186 are not right for the series, but to do 80km/h would rev any engine the same assuming it was coupled to the same box, so thinking about a 4 cyl petrol landy engine, is this going to be a little underpowered and still a bit thirsty? And an original 6 in good condition would be hard to find, more work to maintain and probably no gain in economy.

I guess if I go gas and then change the engine it should be able to be connected to gas also, but would I gain any fuel savings by going to a 4 cyl? I don't know enough about diesels to contemplate fitting one of them, but the price of diesel is more than unleaded sometimes.

Very broad question I know, but I'm looking at my options because while I love my series and love driving it every day, my fuel bill is scary.

[bee utey]

I currently have a 186 red motor in my 109" series 3. The vehicle was originally a 6 cylinder. I'm looking at ways to improve the fuel economy - I use it as a daily driver doing about 90km round trip daily, 5 days a week. About 65km per day is highway driving, so in the interests of economy I sit on about 80km/h which seems to be a comfortable speed for the series without over revving the engine. I know these engines are thirsty, so contemplating putting it on gas while the rebate is around (will cost about $700 net but save half in fuel costs).

My question is whether there is another engine solution that could be done for close to the cost of gas that would be significantly cheaper to run than the 186 yet still give a good running speed without flogging the engine. I would rather go with something that is a bolt in solution to my series 3 gearbox than a full on conversion.

People say the revs of the 186 are not right for the series, but to do 80km/h would rev any engine the same assuming it was coupled to the same box, so thinking about a 4 cyl petrol landy engine, is this going to be a little underpowered and still a bit thirsty? And an original 6 in good condition would be hard to find, more work to maintain and probably no gain in economy.

I guess if I go gas and then change the engine it should be able to be connected to gas also, but would I gain any fuel savings by going to a 4 cyl? I don't know enough about diesels to contemplate fitting one of them, but the price of diesel is more than unleaded sometimes.

Very broad question I know, but I'm looking at my options because while I love my series and love driving it every day, my fuel bill is scary.

The 186 engine is already in there. Gas it and you will save money within a couple of months. Oh, and find a second hand gas kit at a wreckers. You could have it fitted at zero net cost to you. Gas conversions are at a low ebb at the moment, get in while there are bargains to be had. The petrol price may soon rocket with Gadaffi's antics.

Otherwise get a disco tdi engine that fits, the cost of its fuel is offset by an approximate doubling of efficiency over the 186. But it will take ages to recoup any engine conversion cost. However you will probably double the value of your vehicle as a turbo diesel.

BTW I still think you're mad commuting in a brick ****house. Get a Laser. On gas.

[mools]

What about an overdrive? I had a fairy one on a series three, but on a 2.25 petrol. I'm not really sure you'll save loads though; I think it'll drop you about half a gear in revs.

Don't seem to hear much about overdrives over here and judging by what there worth in the UK would probably cost more than gas anyway.

The most effective way I found to improve economy was to follow a lorry at a VERY short distance; not for the feint hearted, not very safe and probably not very practical for commuting either.

Ian.

[hesguitar]

What about an Isuzu 4JB1 or 4JG2 engine? I was looking in to an engine conversion as well (I've got a LR 6 on gas) and was seriously considering getting a kit from M&D engineering in england. Their Isuzu kit seemed like the best option as the engines have been in production for a long time and they're in every second holden rodeo so there's loads around to scavenge from.

[Dougal]

What about an Isuzu 4JB1 or 4JG2 engine? I was looking in to an engine conversion as well (I've got a LR 6 on gas) and was seriously considering getting a kit from M&D engineering in england. Their Isuzu kit seemed like the best option as the engines have been in production for a long time and they're in every second holden rodeo so there's loads around to scavenge from.

The 3 litre 4JH1 is the best of those engines. Later so more refined than the 4JB1T but still mechanical control and direct injection unlike the 4JG2.

[mark2]

A high ratio transfer case works well with a Holden 6. It will help economy and make cruising at 100 much more pleasant. Plus low range is unaffected, unlike with a 3.54 diff change. But as said, why not buy a cheap japanese 4 banger for a commuter? For the cost of a diesel conversion you'd get a decent 4cyl with air con. And a diesel conversion will still need ratio changes.

[clubagreenie]

What about just throwing some RR diffs in? Unless you have a salisbury back end it would be cheap.

[Blknight.aus]

find and drop in the tdi200 and wind the fuel/boost way back.

[d2dave]

find and drop in the tdi200 and wind the fuel/boost way back.

Dave
Would a series gearbox handle the torque of a 200 tdi?

Dave.

[pfillery]

I just got rid of my crappy 4 banger when I registered the landy - the cost of buying another car, $600 plus per year to register, another $150 per year for bomb insurance, and I spent more time under the bonnet of my barina in a month than I've spent under the bonnet of the landy in 6 months. Cost me more to repair than the landy too.

Trouble is, I'd take the train if it was significantly cheaper, but it takes longer by train than by car, would cost close to $60 a week to commute by train with travel to and from the station not included, plus a 15 minute walk to work at the other end because they won't let me take my bicycle on the train. My weekly fuel bill currently isn't much over this but the convenience of the car is an obvious benefit.