Outer Limits 4x4 Board

How does the old Rover V8 go on lpg? are they prone to failure (like the Nissan 4.2)? or do they love the stuff?

been considering an old rangie or Disco 1 (or 2 if in the price range) for a while, but could only make it work if it was LPG powered.

Ok the injected models (3.5 3.9) love the stuff.
The rockhammer boys did very well with there 3.9 buggy on gas but had a MSD ignition system running it aswell.
Another mate has a 3.9 on straight gas and it goes very well indeed.
Both were Gas research Gas carbys.
Earlier carby models i dont know

dual fuel is not a strong point on the rovers.

straight gas on the other hand is scweeeeet!

this is all IMHO ofcourse.

Grimace, would be straight gas, i don't like the compromise of dual fuel personally on any rig.

but mechanically they stand up ok yeah?

bad_religion_au wrote:Grimace, would be straight gas, i don't like the compromise of dual fuel personally on any rig.

but mechanically they stand up ok yeah?

yes. Upgrade leads and plugs to suit ofcourse.

Also make sure you put the effort in to get it tuned aswell. I have found that even with regular high octane pump fuel the rover V8 loves some further advanced timing.

I assume that the theory would apply even more so for straight gas.

EDIT: just want to add to this that as Nottie has mentioned the rockhammer boys had straight gas on the buggy, and that had plenty of up and go, sounded sweet, and ran really well through out the rev range.

dammit. that was the last excuse i had for not joining the prince of darkness side...

better start saving the sheckles.

I have dual fuel on my carby 3.5 101 and it runs like a dream.

Garry

I have got a wolf 3d 500 running dual gas and petrol with sep maps for each. Works a treat.

we talking range rover or discos or what?

i got the 95 disco 3.9 v8 on both petty and gas, has ups and downs on freeway gas is sweet but soon as it comes to city driving forget it
i dont have much of an air box/filter left at the moment as its a bitch and loves to back fire, iv just replaced the rubber tubbing between the air flow meter back to the inlet as she back fired 3-4 times and blew the bugga clean in half turning onto stud road on the way to work one morning

[quote="matthewK"]we talking range rover or discos or what?

i got the 95 disco 3.9 v8 on both petty and gas, has ups and downs on freeway gas is sweet but soon as it comes to city driving forget it
i dont have much of an air box/filter left at the moment as its a bitch and loves to back fire, iv just replaced the rubber tubbing between the air flow meter back to the inlet as she back fired 3-4 times and blew the bugga clean in half turning onto stud road on the way to work one morning[/quote]

You need to upgrade your ignition systems - plugs and leads in particular. Gas needs a better spark and backfiring is often a symptom of poor leads.

Garry

I've had LPG fitted to my Disco1 3.9 V8 for about 2 years now.
Works well. Not as powerful on LPG as petrol as is expected with the old type of system.

Only ever backfired when it was telling me I needed new spark plugs. The gap had grown a fair bit when I checked and replaced them.
The backfires were pretty mild so no damage.

Yep agree with the above but my old system used to backfire occassionally even with new plugs and 9mm staino core gas leads. The answer is to have a relief system (which I couldnt really fit).

The other way is that a friend who is running a rover 3.9 in his rangie who has had the dizzy recurved for gas and it gives the best setup for a compromise system because it is not too much either way.

With the rebate, the gas injection though is the go if you can make it stack up as it works with the existing setup even if you dont run dual maps it works off a computer control that is setup for the gas and therefore uses the existing sensors etc to set its parameters.

garrycol wrote:

matthewK wrote:we talking range rover or discos or what?

i got the 95 disco 3.9 v8 on both petty and gas, has ups and downs on freeway gas is sweet but soon as it comes to city driving forget it
i dont have much of an air box/filter left at the moment as its a bitch and loves to back fire, iv just replaced the rubber tubbing between the air flow meter back to the inlet as she back fired 3-4 times and blew the bugga clean in half turning onto stud road on the way to work one morning

You need to upgrade your ignition systems - plugs and leads in particular. Gas needs a better spark and backfiring is often a symptom of poor leads.

Garry

first thing i did brand new plugs, brands new leads which also did gas.
all up on plugs and lead i think i spent $150

at the moment id be looking for cheapest way out to fix the problem of the gas

as i have to replace my front axle housing as its cracked and leaking
possible clutch,and gear box seals/gasketsso

best way would be make shore theres more advance on the dizzy when running gas.

Personally if your running duel fuel your foolish to run anything other then premium.

Run the highest octane fuel and tune the car to suit, then its slightly less of a compromise.

I have a 89 Rangie, 3.5 v8 with zf 4sp auto running straight gas, and she runs like a dream!

Going from the old flappy paddle efi to straight gas has been the best thing ive done to the car, so far no issues.

I my opinion it was better to go straight gas with 3 tanks (1 inside, 2 underneath) as my time spent in the bush would realistically by less than 10%, so running out of gas is not really a concern.

I get between 22-25 L/100 kms city driving and 18-19 L/100 kms freeway driving, and there is still a little more work required to get it better. I do not have a predominant 4WD use L/100 figure unfortunately. (the best i was ever able to get was 20 L/100 kms city and 17 L/100 kms on the freeway with petrol)

The modification the car carries in regards to the gas system are:
1. Upgraded ignition - IC&E coil, IC&E leads
2. Timing - 35 degrees advance static timing (my distributor is rebuilt, so both mechanical and vacuum work)
3. HM Headers w/ 2.5 in exhaust
4. Silly pod style air filter (in the process of installing a similar to original style canister to suck cooler air, not hot air!)

And I did stick with the EFI manifold setup.

I plan to get better economy by installing the new air filter system, some more tuning is required and some road tyres. The ultimate goal is to get 20 L/100 kms city driving

GRIMACE wrote:Personally if your running duel fuel your foolish to run anything other then premium.

Run the highest octane fuel and tune the car to suit, then its slightly less of a compromise.

the way this thing sux feul your joking right hehehe i jump between 91 and 95,
i used maybe a quater a tank a day going to and from work on petty from doveton to ringwood up stud road

i had a mech look at it 4 months ago i asked him to tune and stuff as its all electronic crap, he recond it was auto tune and he couldnt really tune it with the advanced timing etc etc
to which i thought was full of crap only car so far i know off ya cant tune much was the subyroo

matthewK wrote:the way this thing sux feul your joking right hehehe i jump between 91 and 95,
i used maybe a quater a tank a day going to and from work on petty from doveton to ringwood up stud road

i had a mech look at it 4 months ago i asked him to tune and stuff as its all electronic crap, he recond it was auto tune and he couldnt really tune it with the advanced timing etc etc
to which i thought was full of crap only car so far i know off ya cant tune much was the subyroo

I know how you feel re sucking fuel! It does hurt, but I have found that the extra few dollars per tank is negated by the milage you get out of it (provided the vehicle is tuned/timed to suit the higher ron petrol).

Simple example is my car as it is at the moment simply wont run on 91RON, but if I retard the timing about 3 degrees I can run 91. The reason I don't is because in the past I found I got about 60-70ks more to a tank (mix of highway and town driving) from 95 over 91 at that tune.

Granted I could probably increase the 91 milage by retarding the timing further (tuning the car to suit) but that brings down the performance slightly.

At the end of the day I guess what i am tryign to say is the correct tune for each RON petrol should see the higher ron fuels giving slightly better economy and better performance which IMHO negates the extra cost at the pump.

Straight gas is a step up again, I have no experience personally on straight gas to a rover engine but I did research it for a chev V8 many moons ago and it was all sorts of orsum!

rr215 wrote:I have a 89 Rangie, 3.5 v8 with zf 4sp auto running straight gas, and she runs like a dream!

Going from the old flappy paddle efi to straight gas has been the best thing ive done to the car, so far no issues.

I my opinion it was better to go straight gas with 3 tanks (1 inside, 2 underneath) as my time spent in the bush would realistically by less than 10%, so running out of gas is not really a concern.

I get between 22-25 L/100 kms city driving and 18-19 L/100 kms freeway driving, and there is still a little more work required to get it better. I do not have a predominant 4WD use L/100 figure unfortunately. (the best i was ever able to get was 20 L/100 kms city and 17 L/100 kms on the freeway with petrol)

The modification the car carries in regards to the gas system are:
1. Upgraded ignition - IC&E coil, IC&E leads
2. Timing - 35 degrees advance static timing (my distributor is rebuilt, so both mechanical and vacuum work)
3. HM Headers w/ 2.5 in exhaust
4. Silly pod style air filter (in the process of installing a similar to original style canister to suck cooler air, not hot air!)

And I did stick with the EFI manifold setup.

I plan to get better economy by installing the new air filter system, some more tuning is required and some road tyres. The ultimate goal is to get 20 L/100 kms city driving

I would assume we are talking a Gas research aus Gas carb

Apparently there is a spot on them for a TPS sensor so if needed (run out of gas in shit spot) You can still run petrol thru the motor. When running on Gas the whole computer system is shut off. Bit more in the wiring but a very good idea in my opinion.
Straight Gas is a thing of beauty in my opinion.

Do you need to upgrade any components in an old carby v8 to run gas e.g valves.

Just thought i would add that i just had my 3.9 gas tuned as it was using 55 litres for a 100 ks. Needless to say it was way out.

But anyway they love gas it made 2 less killer wasps on gas than petrol but heres the funny bit it actualy made more tourque.
And another interesting point is i change tyres since last time from 30s to 35s
It lost 4 killer wasps on both.
Anyway i reckon ya could do a lot worse for the fuel saving.
Cheers Damo

I have a 3.5 old rover with a Holley carby that leaks petrol like a bastard so it's permanately on gas....no probs here

There is nothing wrong with running dual fuel if it's all set up correctly and tuned to run well on both , my 3.9 v8 RRC runs LPG as well as petrol but slightly less power and it's hardly noticeable. it also runs the old impco mixer. Initially I had a naked timing module that controlled the ignition timing for LPG , it's been replaced by Bruce Davis with one of these little units which hooks up to the side of the Dizzy


no issues so far until I install the supercharger

My rangie had LPG fitted way back in 1992 at 20,000k's by my dad. Never missed a beat on LPG right up to 250,000k's.. 95% of the driving was on LPG and would only have driven on Petrol when it ran out of gas. I bought the car and drove for over 50,000k's on gas then had it taken out so I could then fit my engel fridge (wish I didn't now as fuel prices hit the roof 6months later!! )

Now the rangie has hit about 350,000k's and still going strong after spending 80% of its life on LPG (the motor hasn't been touched at all..never even had the heads off!! )

Must admit when it was on LPG it ran better than on fuel..but id say it was tuned for LPG.

Camo

Zombie wrote:Do you need to upgrade any components in an old carby v8 to run gas e.g valves.

No, Aluminium heads already have hardened valve seats

matthewK wrote:

GRIMACE wrote:Personally if your running duel fuel your foolish to run anything other then premium.

Run the highest octane fuel and tune the car to suit, then its slightly less of a compromise.

the way this thing sux feul your joking right hehehe i jump between 91 and 95,
i used maybe a quater a tank a day going to and from work on petty from doveton to ringwood up stud road

i had a mech look at it 4 months ago i asked him to tune and stuff as its all electronic crap, he recond it was auto tune and he couldnt really tune it with the advanced timing etc etc
to which i thought was full of crap only car so far i know off ya cant tune much was the subyroo

I fink ull fnd, cnt chun much, juzt adfanz timeng, unlezzzz chng toon rezizztor or pigbak puta

I have had a few issues with the gas backfiring through the airbox on my 97 disco. I put the correct gas plugs in and then changed leads, still occured. So then i sepereted the leads so there was no contact at all and a min gap of 15mm between any lead to lead contact. Problem sorted. Runs aswell as regular fuel. I am using the flashlube system, because of how dry the gas is and it also helps to clean carbon deposits. Hope this helps.

luv4bee'n wrote:I have had a few issues with the gas backfiring through the airbox on my 97 disco. I put the correct gas plugs in and then changed leads, still occured. So then i sepereted the leads so there was no contact at all and a min gap of 15mm between any lead to lead contact. Problem sorted. Runs aswell as regular fuel. I am using the flashlube system, because of how dry the gas is and it also helps to clean carbon deposits. Hope this helps.

More advance on the dizzy helps as well.

If you were to put a megajolt in place for the timing then you would be able to switch the timing on the fly, allowing for reliable dual fuel operation.