DJ fuel consumption and ignition timing.

[syncrosimon]

In August last before we embarked on the drive to Sweden I reset the ignition timing on the syncro to 5 degs, or where you set it to run on regular 95 ron petrol. Over the last 5000 miles since then I have averaged 21.5mpg.

Before Easter I reset the timing back to 10 degs where it should be, and began using Shell V-power and sainsburys super, the fuel consumption leapt back up to 24.5 mpg and I managed 350 miles or 560km (before reserve)on a tank coming back from Norfolk cruising at around the 65 to 70 mph 115-120 kmh on the A303 etc.

Prior to August I had been getting around 24mpg on a good run.

When the ignition was set to 5 degs I noticed that the DJ would run rich at a cruise, up to lambda 1.10, ( I have an exhaust lambda gauge fitted) since reverting back to 10 degs she now cruises at lambda 1 and I am getting the economy.

2000 miles on 5 degs at 21.5mpg @ £1.319 = £552.
2000 miles on 10 degs at 24.5 mpg @ £1.359 = £502.

I shall stick to 10 degs and super, sainsburys are selling it quite cheap at the moment.

I now drive like a pussy round town, and save the flat out for the motorway. Thats how I find I achieve the best economy versus speed equilibrium.

Simon.

[PetenAli]

Thanks Simon - thats useful info. Mine was set at 10 deg btdc when I bought it and after a while I reset it to 5 degrees and started running 95 ron. Earlier this year I went back to super unleaded and 10 deg btdc. Sadly I didn't take alternative fuel consumption figures but, totally unscientifically, I am sure that it runs better - especially in respect of better torque which is most noticeable on hills. I stick to about 60mph on the motorway but most driving to date has been round Cornwall so that brings down the consumption. Going up to Dartmoor at the weekend so will check it proberly then.

This will probably sound like secrilege to you but having driven Rollercoaster's recently converted EJ22 Syncro Caravelle I am still looking to convert to Scooby power later in the year - the difference was so impressive. On the lookout for a 2000 - 2003 2.5 Legacy if you happen to come across one!

Pete

[KINGPRAWN]

Thanks Simon - thats useful info. Mine was set at 10 deg btdc when I bought it and after a while I reset it to 5 degrees and started running 95 ron. Earlier this year I went back to super unleaded and 10 deg btdc. Sadly I didn't take alternative fuel consumption figures but, totally unscientifically, I am sure that it runs better - especially in respect of better torque which is most noticeable on hills. I stick to about 60mph on the motorway but most driving to date has been round Cornwall so that brings down the consumption. Going up to Dartmoor at the weekend so will check it proberly then.

This will probably sound like secrilege to you but having driven Rollercoaster's recently converted EJ22 Syncro Caravelle I am still looking to convert to Scooby power later in the year - the difference was so impressive. On the lookout for a 2000 - 2003 2.5 Legacy if you happen to come across one!

Pete

two friends both did the scubbie conversion, done by a chap i essex i think?...both loved the power but ...with the extra power found that the brakes wern,t up to the job nor the suspension!....and both couldn't keep them going in the wet!...both were navel officers, so bottomless pockets, just kept chucking money at them but nobody could sort it!...both got so pissed off they're both history now( vans that is not the blokes)its not the ultimate answer..possibily!!!....how do you adjust the timing? do you need special kit? my 2.1 dj gives aprox 400km to a tank...not sure how that works out...i'm in penzance

[syncrosimon]

I have found that the fuel consumption of the 2.1 is improved by staying on roads where you can keep 4th gear, and then where you have to drive around town or on slow roads drive her like there is an egg on the pedal. On the motorway I will always get more than 300km before half tank, this is reduced to around 250 if i am blating around town. I have now virtually given up the brake pedal, and just read the road ahead, if there is a junction coming up why keep accelerating, make people wait behind you, pull over when you get the chance to let them by. Enjoy the journey.

If your driving is mainly around town or the Cornish lanes I dont think that you will achieve 24mpg, unless you drive very carefully.

You set the ignition timing at the distributor with a timing light, you need to tune the tick-over mixture on the airflow meter afterwards. I have a good local source of super unleaded close by, which brings the price down.

I found that I could not get Super at Morrisons Wincanton A303, Winterbourne Stoke A303, or at Tesco's Royston A505. This was a pain in the ass. I feel the DJ runs best on Shell V-Power, but this is just likely the placebo effect. (Although 5th Gear did a petrol show down and found that Shell V-Power did give more BHP than standard fuels)

[PetenAli]

KINGPRAWN

If you want to pm me we can arrange for you call in when you are passing and I'll show you how to do the timing - you'll need to get it filled with 98RON as soon as possible though. As Syncrosimon says, it can be a pain when you can't find 98RON. I think the nearest to you might be Loggans Shell at Hayle although Tesco in PZ may do it.

As far as the Subaru conversion goes I'm going for all RJES parts and Brickwerks are going to do it. I've started this thread to help find a suitable donor but no joy yet: https://club8090.co.uk/forum/viewtopic.php?f=12&t=84747" onclick="window.open(this.href);return false;

There is loads of info about the conversion on this and other forums and lots of people have done them successfully although, as you say, with any conversion you need to think about things like brakes, transmission etc.

Going up to Dartmoor on Friday so will check mpg accurately when I fill up.

[silverbullet]

60-65 mph for me in the 2.6, definitely see the mileage fall off quite dramatically if the speed creeps any higher. I recall a Uni Fluid Dynamics lecturer telling us all that vehicle aerodynamics only come into play at speeds in exscess of the legal limit anyway, regardless of the vehicle design or coefficient of drag.

Hypermiling is the way to drive: read the road ahead, let the speed fall off gently on long hills (you'll get it back for free on the other side) and don't flog it in too high a gear (change down and let the motor spin, it's not the same as revving the nuts off it. Think of a cyclist at optimum cadence)

Just remember to keep rolling - it's the stop/starts that are the killer - along with carrying junk. This includes unused seats in the back if you drive a Caravelle!

Plus if you go too fast, no-one gets the chance of a good look at what they could be driving

[PetenAli]

When the ignition was set to 5 degs I noticed that the DJ would run rich at a cruise, up to lambda 1.10, ( I have an exhaust lambda gauge fitted) since reverting back to 10 degs she now cruises at lambda 1 and I am getting the economy.

Can you explain what lambda is please? I've been hearing about it for years but never actually worked out what it means. The forum is so helpful and I'm starting to lose my anxiety about asking what might seem like dumb questions!

[silverbullet]

Lambda sensors generate a voltage based on the percentage of oxygen needed to completely combust the excess fuel in the exhaust gases (phew!)
In reality what this means is, if you read off the lambda ratio you can see if it's running rich or lean. A value of 1 means stoichometric air/fuel ratio of 14.7:1 - the theoretical optimum - but it can be different when cruising at light throttle or when booting it at full load, maybe 18:1 or only 11:1 respectively.
Wikipedia does explain it a little clearer!

[bikermike87]

My 18mpg is somewhat concerning. I've been told it's set up for 98 octain and I have been using shell v power.
I'm thinking about getting it in with Steve at Gasure, maybe he could give it a once over.
Big 16/75/225 may be impacting and the fact my temperature gauge never really goes up
I was expecting 20mpg as normal for a tin top 2.1dj syncro, but this post suggests better

[PetenAli]

Thanks for the lambda explanation - I'll get on Wikipedia as well!

I think Syncrosimon's posts on here show that you need to experiment with timing etc and work on your driving style to get the best mpg.

[syncrosimon]

My 18mpg is somewhat concerning. I've been told it's set up for 98 octain and I have been using shell v power.
I'm thinking about getting it in with Steve at Gasure, maybe he could give it a once over.
Big 16/75/225 may be impacting and the fact my temperature gauge never really goes up
I was expecting 20mpg as normal for a tin top 2.1dj syncro, but this post suggests better

I think it depends on where and how you drive. Mine will definitely do 20mpg when just thrashing around on short trips. It's on the longer runs that you can get the better fuel consumption. The 24.5mpg was gained mostly on motorway and A roads.

A good tune up is worth a great deal.

[syncropaddy]

Hypermiling is the way to drive: read the road ahead, let the speed fall off gently on long hills (you'll get it back for free on the other side) and don't flog it in too high a gear (change down and let the motor spin, it's not the same as revving the nuts off it. Think of a cyclist at optimum cadence)

Been reading this thread with interest as I started Syncro life with a 2.1DJ which had the 5 degree thing done and was running on 95 ron. The van was empty inside so was probably as light as you can get and on long runs would manage 26 to the gallon at best. I experimented at lot with the 'hypermiling technique' when I was shunting around locally and was reasonably pleased with the results and I use that technique now in my E220 to great effect.

Ians point about being in the right gear is critical. I recently had the use of my young lads Passat 4motion which has an AFN 130 TDi in it (I think) and is equipped with a trip computer. I was playing around with it as I was interested which gear at a given speed gave the best fuel consumption around my locality. At 40mph on a flat road in 4th gear gave better fuel consumption that in 5th or 6th and interestingly 6th gear was really of no value until speeds of 65mph plus were reached. The engine seemed to hit its sweet spot at around 1900 rpm and until those revs were reached there was little point in changing up as the engine felt under pressure. I would not be surprised if the same can be said about a JX at about 2500 rpm as it seems to like speeds from that point on to 4000 rpm.

Driving technique and the amount of crap we carry about in our vehicles is critical to fuel consumption.

[bikermike87]

My 18mpg is somewhat concerning. I've been told it's set up for 98 octain and I have been using shell v power.
I'm thinking about getting it in with Steve at Gasure, maybe he could give it a once over.
Big 16/75/225 may be impacting and the fact my temperature gauge never really goes up
I was expecting 20mpg as normal for a tin top 2.1dj syncro, but this post suggests better

I think it depends on where and how you drive. Mine will definitely do 20mpg when just thrashing around on short trips. It's on the longer runs that you can get the better fuel consumption. The 24.5mpg was gained mostly on motorway and A roads.

A good tune up is worth a great deal.

Without sounding silly, I'm pretty sure it's not my driving style, I'm averaging almost 27mpg in the 2wd.
But the syncro tin top, 55mph sitting at 2900rpm over 185miles (all on the motorway) in the syncro and I still can't see past 18mpg
It does have a r&r bed plus cuboards, but I can't imagine it being any heavier than a westy for example.
a nice tune up and maybe some smaller wheels may help! And looking at a possible stat that might be stuck open!

[hotpod]

my dj hightop camper with 16" bfg mt's was averaging 20mpg all last year.
a trip to switzerland last easter with 3 mates and all our snowboard gear averaged a shocking 18mpg.
this year, when i was prepping the van for a trip to holland, i tried a £4 pot of stp fuel conditioner/injector cleaner in a tank of fuel (mine runs much better on 98 ron, ) .on the holland trip with a 90k stove in the back, and the camper fully stocked, i averaged 24.5mpg.
however, how much of this difference can also be explained by the fact that i had also just finally fixed a year old leak from the fuel sender, i just dont know.
i suspect that over the course of a week, a small fuel leak can have quite a large effect on your apparent mpg figures.
i would suggest to anyone who can always smell petrol around the back of the van, to find the source of the smell before trying to work out fuel consumption of the engine.

[KINGPRAWN]

my dj hightop camper with 16" bfg mt's was averaging 20mpg all last year.
a trip to switzerland last easter with 3 mates and all our snowboard gear averaged a shocking 18mpg.
this year, when i was prepping the van for a trip to holland, i tried a £4 pot of stp fuel conditioner/injector cleaner in a tank of fuel (mine runs much better on 98 ron, ) .on the holland trip with a 90k stove in the back, and the camper fully stocked, i averaged 24.5mpg.
however, how much of this difference can also be explained by the fact that i had also just finally fixed a year old leak from the fuel sender, i just dont know.
i suspect that over the course of a week, a small fuel leak can have quite a large effect on your apparent mpg figures.
i would suggest to anyone who can always smell petrol around the back of the van, to find the source of the smell before trying to work out fuel consumption of the engine.

best get me some STP....PRONTO PRONTO!!