Thread: Hi there guys-i just joined up here on Sat nite, n have been reading all this GREAT!!

Hello Byron with a long question
I have 2 rangies 1 3.9 Carbie rangie on gas, but also need it to run on petrol, The book says 6 degrees static, but in my exp this is to low If I were u I would keep advancing the timing until it pings under load in 3rd or 4th gear up a slight hill, then I would back it off till it just dont, that for me is optimal timing for petrol, also it will vary, or it does on my 89 EFI depending on fuel used. Normal Unleaded verses premium, so try the settings and see what happens. On my 3.5 89 I always use premium and the timing is set at 12 degrees.
On my 3.9 the timing was set on 15 degrees but this is a rebuilt modified high comp motor mainly on gas .
My 3.5 89 efi on pet gets 500kms on pet 80 ltres, and on lpg 420kms out of 78 ltres.
My carbie 3.9 with same setup was app 15% higher in consumption
Have fun
Brad

Originally Posted by Bradtot

Hello Byron with a long question
I have 2 rangies 1 3.9 Carbie rangie on gas, but also need it to run on petrol, The book says 6 degrees static, but in my exp this is to low If I were u I would keep advancing the timing until it pings under load in 3rd or 4th gear up a slight hill, then I would back it off till it just dont, that for me is optimal timing for petrol, also it will vary, or it does on my 89 EFI depending on fuel used. Normal Unleaded verses premium, so try the settings and see what happens. On my 3.5 89 I always use premium and the timing is set at 12 degrees.
On my 3.9 the timing was set on 15 degrees but this is a rebuilt modified high comp motor mainly on gas .
My 3.5 89 efi on pet gets 500kms on pet 80 ltres, and on lpg 420kms out of 78 ltres.
My carbie 3.9 with same setup was app 15% higher in consumption
Have fun
Brad

hey man....thanks for that GRRREAT! info.....it's all as I thought/suspected ...

BTW, you know that LPG needs/can take up to/more than 10 degs extra advance than petrol, it's almost impossible to get it to ping in a normal engine.....

but back to petrol - I WAS getting only 240-270 klm per 80 L before replacing the vacuum advance....now it's heaps better....just haven't kept a note of mileage from an entire tank [ I tend to top up when I see it cheap on Tues +Wed's, so have litres purchaed and klms driven and do the calcs = 15.3 L 100klms].....it certainely accelerated and ran well when set @ 12BTDC - but wouldn't top 120 kph.....I must confess I haven't tried its top speed since it's now on 6BTDC....not close enough to a good, clear of traffic n cops freeway/highway near me!....maybe the throttle cable needs checking for full movement range at thottle....

it certainely never pinged accelerating up a hill in 3rd or 4th.....and I've only ever used ULP 91-93 RON....your 3.5 EFI isn't all that different to my 3.9....I'm intrigued you need[?] to run it on Premium [ do you mean 95 RON? or Ultra 98 RON????] as mine could handle 91-93 RON wthout pinging....have you tried it on plain ULP?...mine's Low Compression - wot's your 3.5?? [ as you know, the higher the compression the greater the need for higher RON]

neither your 3.5 nor my 3.9 have knock sensors nor a retard function in the ignition system - so what we dial in and what RON petrol we use is totally up to our choice.....it would be interesting to do compaisons with different tiing settingsand different RON fuels and work out what gives best power and economy.....mmmmm maybe I should start hinting NOW! that I want a 4WD twin roller rolling road and dyno setup for Xmas now!!!! It would be so much easier!!!....Do you think if I started excavating the garage floor now, in anticipation of my loved one coming good with the present it would make her feel guilty enough to get it?

But your figures hae really given me something to work with/go on.....MANY THANKS!!

Byron ..yes I know about the gas advance I have been on gas since 1993.
I use premium because I get more mpg and it is slightly better on economy and power.
My 89 3.5 is 8.13 compression so low. I have a new motor waiting to go in the 89it is 3.9 with high comp pistons as I mainly run gas better comp better for gas.
re the diff comparisons I have already done this over the years I been drivin Rangies... since 1984 and still lovem will not have anything else.
Brad

Originally Posted by Bradtot

Byron ..yes I know about the gas advance I have been on gas since 1993.
I use premium because I get more mpg and it is slightly better on economy and power.
My 89 3.5 is 8.13 compression so low. I have a new motor waiting to go in the 89it is 3.9 with high comp pistons as I mainly run gas better comp better for gas.
re the diff comparisons I have already done this over the years I been drivin Rangies... since 1984 and still lovem will not have anything else.
Brad

Excellent!....even more info....you've now fully answered my Q's....I'll change the timing to 12BTDC 1st thing tomorrow and start using 98 RON.....P.S. - I guess I better tell my G/F that she doesn't HAVE TO buy me the rolling road n Dyno for Xmas now......but sumthing up to the value of would be nice!!

CHEERS!!!

Originally Posted by byron

Excellent!....even more info....you've now fully answered my Q's....I'll change the timing to 12BTDC 1st thing tomorrow and start using 98 RON.....P.S. - I guess I better tell my G/F that she doesn't HAVE TO buy me the rolling road n Dyno for Xmas now......but sumthing up to the value of would be nice!!

CHEERS!!!

BTW....I've had RR's since bout then too....had most models n variations Carbs, EFI, EAS Vogue SE etc but....none on gas tho.....presently have this Disco 93 3.9i auto 7seater since last Dec, a 96 RR 4.6 HSE since new and a 68 2a ex-Oz Army Engineers Corps 109 with a 186 Holen red motor since 98

I was always told that setting the V8 up using Vacuum Timing was the best - as each motor was unique, in their own special LR way

LRH

http://users.bigpond.net.au/ergoff/OTHER.HTM

Now...I've got a couple of Q's [1] what's the best initial dynamic timing for a low copression 3.9i [or maybe? a 3.5i] in a Jan 93 build Disco automatic?...BUT WAIT!, there's more!!...it's a "KA" [early type] engine with the Lucas {Prince of Darkness} electronic distributor [with module on side of dizzy]...I bought it last Dec and having had over 20 years experience with Range Rovers thought [ KNEW!!] it had v. bad fuel consumption, even for one of these...typically 23-26 even 28 litres per 100 Km around inner city mostly, driven pretty gently....changed plugs [NGK], cap + rotor [Lucas genuine - ouch! how do they work out cap = $30 and rotor = $60???? to design, make and sell????] and leads [Bosch]...checked everything - or so I thought!...car went pretty well, smooth etc...but on odd occasions of high-ish speed cruising [100 kph+ ] I knew she needed too much throttle pressure to maintain speed....used heaps of fuel....nearly twice as much as my 96 RR 4.6 HSE.....then one day was reading a free issue of the LR Club of NSW magazine I picked up from Graham Cooper's and chanced upon a series of brief "hints" - "If your Rover V8 [with dizzy type] is using heaps of fuel but otherwise running well- CHECK YOUR VACUUM ADVANCE MODULE/CAN FOR LEAKAGE"....they even quoted my horrendous fuel consumption figures!!.....well I pulled off the end of vacuum hose from Plenum and sucked - ****!! I could breath normally, even up to running speed thru it!!! One of those Ah-Ha moments!!!....to cut a long story short I picked up a new one from Cooper's [ cheapest price I could find BTW and Graham even apologised for the price, but there were no alternatives].....NOW to get at the rearmost mounting screw I had to loosen the hold down and twist the body of dizzy for access....I had already checked timing several times before [and it was 12 BTDC] ....replaced the lil bastard and then had to reset timing......THAT'S WHEN I ASKED MYSELF: what setting?....I [now] figured that it had been set so far advanced cos there wasn't any vacuum advance and this was done to get reasonable performance [it was OK as I said but using heaps of gas and needed lots of [too much] throttle for high speed] I KNOW the manual advises 2BTDC +/- 3 but Graham suggested 6BTDC was a "good n safe" setting....so I set it to this[6BTDC]....found that it was a slug [mmmm maybe it's a 3.5??]....so figuring that vacuum advance comes into play more and more as throttle is eased [i.e. higher vacuum] and not really when accelerating [widish open throttle- low vacuum] I reset it back to 12BTDC to see what happened.....well it went much better [well of course it would!] in acceleration and didn't ping ever, at all [never did, even before] so I left it there.......Later when on a longish run of freeway I tried out performance it wasn't able to top 120kph, even with a long run up and when you floored her at, say 100kph - NOTHING much happened...[I know these should be good for 160kph minimum] and she wouldn't go over 115-120 kph......mmmmmm maybe too much advance?????......and no pinging cos it's a low comp????

my god did you copy and paste that .......i bet you own a nissan pootrol really don't you but in order to penatrate the higher circle of the landrover elite, you needed to sound convincing..........