Ideas for improved economy from Holden 186 in SIII

[pfillery]

Yeah, yeah, I know. It's a Land Rover so it will be thirsty! But does anyone have any tips for better miles per gallon for a Holden 6 powered Series 3 LWB.

The obvious solution is gas but I want to avoid the bloody great tank in the back since I've discovered underbody tanks are not viable in dollar or space terms, plus I want to try and retain (as much as possible) the original feel of the car. Gas will take aproximately 1800 litres to break even assuming both petrol and gas remain where they are.

Are there any tips from those of you who have done something to the 186 to improve economy? More power isn't the object, most say the 186 almost has too much power already for the Landy gearbox.

Maybe changing the air filter from the original? Any ideas.

[PhilipA]

I do not know about your specific case but I can give you some guidelines.

1 gearing- the higher the gearing within reason, the better economy so maybe if you have 4.7 diffs go to 3.54.

2 advance - try the maximum advance that he engine will stand without pinging, by advancing 1 degree static at a time until you get pinging then back off a couple of degrees.
3 Fuel mixture- Get an adjustable main jet and tune it as lean as possible on cruise consistent with smooth running. This may be a problem with an old iron head 186 as the leaner the hotter and the more chance of burnt valves, seat recession on unleaded. I would suggest a dyno and exhaust sniffer for this but you probably don't want to spend the money.

4 - weight/air resistance. Take off the roof racks, and ditch all the unecessary gear inside, maybe even the spare for local trips.

5 tyres - a modern tyre with mild tread will use far less juice than bar treads.
6- ensure the engine is in good condition, plugs, wires, dizzy, coil, carby not leaking or worn out needle and seat, good compression.
Regards Philip A

[strangy]

A Hiclone will give up to 15% better fuel consumption and more power. The Tv said so. Put one in each inlet port and you will get a 90% increase!
:angel::angel:

My experience with the 186 is that apart from extractors, good timing and obviously good plugs and filters there is little to be done without starting to spend big and the results wont justify the outlay (i.e carby, inlet manifold mods, head replacement / work)
You could fit a later model commodore head with EFI. I think it was the VK had EFI 12 port heads. Again the expense wouldnt justify the gains overall. But would be good talking point.
An overdrive might be the best mod you could do.

cheers

[pfillery]

A Hiclone will give up to 15% better fuel consumption and more power. The Tv said so. Put one in each inlet port and you will get a 90% increase!
:angel::angel:

My experience with the 186 is that apart from extractors, good timing and obviously good plugs and filters there is little to be done without starting to spend big and the results wont justify the outlay (i.e carby, inlet manifold mods, head replacement / work)
You could fit a later model commodore head with EFI. I think it was the VK had EFI 12 port heads. Again the expense wouldnt justify the gains overall. But would be good talking point.
An overdrive might be the best mod you could do.

cheers

From what I've been told a 186 with an overdrive will shred the overdrive or the gearbox pretty quickly because it has too much power for it. I figure that I have to outlay about $1100 for gas after the rebate, I ruin the originality of the car and lose some cargo space. I will consider rebuilding or kitting the carby, tuning a bit and see where it goes from there. I'm not sure if changin the archaic oil bath filter for the standard holden type air filter for city driving.

Not much evidence to say that hiclones really work!!!

[PAT303]

I had a 186 with yella terra heads,twin barrel stromy with a power cam and 3'' sports system and I drove it like I stole it and never broke anything.The series gearbox's are allot stronger than people give them credit for.I'd get higher diffs. Pat

[bee utey]

Decent spark will allow you to run lean mixtures. I would fit an electronic dissy from a blue motor, adjustable main jet sounds like a good idea, viscous or electric fan, then an O2 sensor and a little mixture read-out kit from Jaycar so you can see what the mixture is doing.
Later model head and extractors if you can fit them in.
Oh and take the roof off and drive with the windscreen down. Felt hat with cord needed.

[clubagreenie]

Diffs as said, XE/XF falcon webber carby (included elec choke) jetted correctly makes it go much better, won't be worried off road by angles and is much nicer to drive and there is an adaptor plate off the shelf. Extractors, better exhaust, if you want to go all the way yella terra head and cam done right will even out fuel vs performance.

[pfillery]

I had a 186 with yella terra heads,twin barrel stromy with a power cam and 3'' sports system and I drove it like I stole it and never broke anything.The series gearbox's are allot stronger than people give them credit for.I'd get higher diffs. Pat

Is it possible people who convert a 4 cyl Landy to a holden 6 might be the ones having problems, ie is it a different gearbox? Mine was originally a 6. Considering they came out with 3.5 litre V8s as well, I can't see the boxes not being able to handle a 3.3 red 6.

[pfillery]

So to change the diff is that just the diff centre or do you have to drop the whole diff and replace the whole thing including the painful bleeding of the brakes?

If mine is the standard series 3 diff for a 6 cylinder petrol, what diff will give me better economy? And does the ratio of the front diff need to change as well? What sort of land rover or other diff centre will go straight in without a fight?

[clubagreenie]

Is it possible people who convert a 4 cyl Landy to a holden 6 might be the ones having problems, ie is it a different gearbox? Mine was originally a 6. Considering they came out with 3.5 litre V8s as well, I can't see the boxes not being able to handle a 3.3 red 6.

Land Rovers don't break axles/diffs/gearboxes, drivers do.

Just the diff centre/housing from a RRC will fit in.

[Bigbjorn]

If you are chasing fuel economy and don't want to spend much, pretty well the only effective thing you can do other than keeping the engine in tune is to change to 3.54:1 diffs.

There a quite a few modifications that should be done to make the Holden more suited to a radically different application. Unfortunately almost no-one ever did. The usual approach being to buy a worn second hand engine and bung it in as is.

Fuel consumption of a Land Rover is always going to be high. You are battling the enemies, mass, revs, wind resistance, rolling resistance.

[pfillery]

If you are chasing fuel economy and don't want to spend much, pretty well the only effective thing you can do other than keeping the engine in tune is to change to 3.54:1 diffs.

There a quite a few modifications that should be done to make the Holden more suited to a radically different application. Unfortunately almost no-one ever did. The usual approach being to buy a worn second hand engine and bung it in as is.

Fuel consumption of a Land Rover is always going to be high. You are battling the enemies, mass, revs, wind resistance, rolling resistance.

I believe when mine was done back in 2004 the conundrum was a choice between a very expensive full rebuild of the original 6 which had seized after sitting in a shed for 20 years or a conversion to a 186. The motor was reconditioned prior to installing it because even a recon 186 conversion was cheaper than rebuilding the original 6 by about half apparently. It was supposedly converted to unleaded as well because the previous owner was told he wouldn't have to use an upper cylinder lubricant, so I'm guessing they put hardened valves and seats in it. Seems to run pretty well except when it idles all the loose moving parts on the car rattle around (ie bonnet, toolbox lids etc) but with the throttle on a fraction or the choke on the car is as quiet and as smooth as you'd expect a kingswood to be, it feels pretty good for a 1960's motor (186A series engine so I think about 1966 or so).

It does seem as though you are driving a brick into the wind in a storm but isn't that half the fun of driving a landrover?

I have only ever half filled the tank on mine but with a $40 fill I'm finding I can go 3 and a half days of commuting to and from work which is about 250km roughly - $40 in a barina was 700km!

[strangy]

From what I've been told a 186 with an overdrive will shred the overdrive or the gearbox pretty quickly because it has too much power for it. I figure that I have to outlay about $1100 for gas after the rebate, I ruin the originality of the car and lose some cargo space. I will consider rebuilding or kitting the carby, tuning a bit and see where it goes from there. I'm not sure if changin the archaic oil bath filter for the standard holden type air filter for city driving.

Not much evidence to say that hiclones really work!!!

Individual experience only here, with a 2a and a 186 with fairy o/drive was that it wasnt going to die easily. The old girl was given a hiding and always dropped out nice oil without metal. An axle and a rear diff were lost but that was due to very agressive driving behaviour (ie 2 x 20 year old boys in the bush with mud rocks and creeks:angel:)
How much were you hoping to gain and how much did you hope to spend.
the 2a used to do around 17l/100 without o/drive (90km/h max) and about 14l/100 with the o/drive (100km max, it was still a brick as you say)

cheers

[D mac]

This may not be really helpful but here goes.
Tune fuel a little leaner and colder plugs.
I find that driving by a tacho and not revving
over 3200 helps.
The fun thing in a series 3 is that you get to see a lot
more of the country because your'e going slower.

Cheers

Don

[PAT303]

RRC diff centres are a straight bolt in fit.Very easy job. Pat

[DeeJay]

RRC diff centres are a straight bolt in fit.Very easy job. Pat

I suspect the Series 3 6cyls came out with Salisbury diffs. I had the exact problem with a SWB 186 Holden powered vehicle. PIA & very frustrating on the Hwy.
I found the most sensible & economical conversion was to advertise it & convert it to cash.
I put that towards a stage 1 :)- then a County.:):)

[Disco44]

I had a 186 with yella terra heads,twin barrel stromy with a power cam and 3'' sports system and I drove it like I stole it and never broke anything.The series gearbox's are allot stronger than people give them credit for.I'd get higher diffs. Pat

I too had a 186S (192) in my series 3 and the standard box handled it OK.Never broke anything too.But I had 3.54 diffs in it , which IMHO were a bit high.I think a 4.1 which were once available would be a better option.

[clubagreenie]

I managed to score a new (still in timber crate) salisbury 3.54 centre for a paltry $50- many years ago. Biggest debate was whether to fit it or sell it for a what was at the time a huge profit

[UNDEROVER]

I had a 186 in a 2A for twelve years which was used daily as a work truck towing a large trailer with scaffold etc, as well as being used to drag a 15ft tinny up the beach to Double Island point on a regular basis.
Motor was 60 thou oversize, mild cam, bit of head work, extractors and a holley carb. After I went from one end of the vehicle to the other to take out any slop in the 30 year old drivetrain in the first year, I didn't break a single axle, diff etc for the next eleven, so strength is no issue in my book.
An offset intermediate shaft and bigger high range gear in the transfer case kept the revs under control whilst on the highway and also maintaining original low range gearing for offroad.
This certainly aided in keeping fuel usage acceptable as well as being particular with service intervals, tuning and overall maintenance of the vehicle including tyre pressures.
It'll never match current day fuel figures, but by the same token I always enjoyed the power that was on tap when required, provided I had my wallet with me. A 45 litre tank doesn't go far when the secondaries of a holley are wide open!;)

[BigJon]

Is it possible people who convert a 4 cyl Landy to a holden 6 might be the ones having problems, ie is it a different gearbox? Mine was originally a 6. Considering they came out with 3.5 litre V8s as well, I can't see the boxes not being able to handle a 3.3 red 6.

Series III with a V8 is Stage One. Different gearbox entirely. LT95, possibly the strongest ever factory fitted LR gearbox.

[pfillery]

I had a 186 in a 2A for twelve years which was used daily as a work truck towing a large trailer with scaffold etc, as well as being used to drag a 15ft tinny up the beach to Double Island point on a regular basis.
Motor was 60 thou oversize, mild cam, bit of head work, extractors and a holley carb. After I went from one end of the vehicle to the other to take out any slop in the 30 year old drivetrain in the first year, I didn't break a single axle, diff etc for the next eleven, so strength is no issue in my book.
An offset intermediate shaft and bigger high range gear in the transfer case kept the revs under control whilst on the highway and also maintaining original low range gearing for offroad.
This certainly aided in keeping fuel usage acceptable as well as being particular with service intervals, tuning and overall maintenance of the vehicle including tyre pressures.
It'll never match current day fuel figures, but by the same token I always enjoyed the power that was on tap when required, provided I had my wallet with me. A 45 litre tank doesn't go far when the secondaries of a holley are wide open!;)

When you say you took out the slop in the drivetrain, did you remove all play in the driveshafts etc? How did you do this? I have some play ie I can turn the rear driveshaft a small amount with the handbrake off, is this the norm?

[stage one]

You might be able to track down the adjustable main jet you could get for the holden stromburg? I've seen a couple, years ago, looks a bit like a fuel tap that screws in where the main jet go's. Can go from no fuel at all to heaps.

[Disco44]

Series III with a V8 is Stage One. Different gearbox entirely. LT95, possibly the strongest ever factory fitted LR gearbox.

I agree wholeheartedly Big Jon.The LT95 was the toughest box LR put out. I remember reading in a British magazine a few years ago,an interview with the designer.He thought that ,in hindsight,that the box was over engineered for it's intended purpose,the early RR.I once took one apart just to have a look and was very impressed with it.It's mated surfaces instead of gaskets is just one innovation.But with the transfer case attached it was one hell of a heavy box.
John

[dieseldo]

I had a 186 in a 2A for years. Drove Melbourne to Darwin and back with an average of 14l/100km. Standard motor with 2" exhaust out the passenger side. Had the RR diff in the back, a locking one with the long bolt that screws in from the driver's side axle. Kept the standard diff in the front. I wouldn't recommend this, unless you want to end up with a short wheel base 2A!!;).
I also had an HR panel van with a 186 in it that returned 10l/100km. Bit more aerodynamic than a 2A though. That had extractors, 2" exhaust, mild cam and a 350 holley on an x2 manifold. I loved that car.[happycry]

[PhilipA]

I agree wholeheartedly Big Jon.The LT95 was the toughest box LR put out. I remember reading in a British magazine a few years ago,an interview with the designer.

Yes that is true , but there is a different reason.
The box was designed for the 101? Gun tractor espcially to provide a take off at same shaft speed to have a powered trailer/gun.
LR did not have enough money to design another new transmission for the RR and the LT95 was used , also because they needed constant 4wd as they did not want to put a rear Salisbury in because its weight would have affected the ride.
So the RRC was saddled with a truck box for 12or so years.
BUT they are strong . I saw one about 20 years ago behind a 400 Chev for 10 years with no problems. Biggest problems are the intermediate shaft and the diff shims.
Regards Philip A

[stage one]

Just in case you wanted to know,Here's a photo of my old LT 95 out of a stage one v8, that thing hanging off the back is an overdrive. I loved that over drive! even as I have the higher ratio gears in my new LT, it's just not the same, it's the 5th I've always wanted. It will be getting a reco and back on. Oh, and just for the record, an LT 95 out of a Range Rover has a bout a 20mm shorter front output extention housing, I only found out when I went to bolt up the front tail shaft to my new one! Just a little $360 later, and the lengthed tail shaft fits nicely. They are huge, and would most likely take more effort and engineering to fit than it's worth.