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

**byron** · 28th August 2006, 04:01 PM

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????

So at home I first reset her to 8BTDC and ran it for a week or so and then 6BTDC [no discernable difference between them.....did a fuel consumption test and got 15.3 L/100Klm around city....pretty good I think.

NOW.....my Q is: does anyone KNOW the optimum timing setting[/s?] for one of these engines.....ALL advice gratefully received and if you know what you're talking about from experience, well that's even more welcome!....

I said this was my 1st Q....it is on this forum, which BTW, is probably the best online LR forum on the net....and I take part or just read a fair few....AND IT'S AUSSIE!!!.....I'll ask my other Q's on new threads.

**rangieman** · 28th August 2006, 04:15 PM

Welcome mate wow what along breath you take
sorry cant help but when i normaly do the timimng on any petrol motor i set it at factory settings and if not happy i go with my heart and adjust it to what i feel is good

**byron** · 28th August 2006, 04:51 PM

Originally Posted by rangieman

Welcome mate wow what along breath you take
sorry cant help but when i normaly do the timimng on any petrol motor i set it at factory settings and if not happy i go with my heart and adjust it to what i feel is good

Yeah....me too....but I s'pose wot I meant was..."Does anyone/has anyone FOUND a really good setting?".....my gut/heart suggests 6BTDC is "it"....and Graham Cooper says so to - reckons it's best average setting if you don't want to spend $1,500.00 odd to Superchip it and have it dynoed....but I wanted to know if anyone had found otherwise?

**discowhite** · 28th August 2006, 05:01 PM

i was running mine at 3deg without the vac advance hooked up.
best i got was 450k from 80l
average 350 around town and 400 hwy.

phil

tombraider · 28th August 2006, 05:10 PM

Originally Posted by byron

Yeah....me too....but I s'pose wot I meant was..."Does anyone/has anyone FOUND a really good setting?".....my gut/heart suggests 6BTDC is "it"....and Graham Cooper says so to - reckons it's best average setting if you don't want to spend $1,500.00 odd to Superchip it and have it dynoed....but I wanted to know if anyone had found otherwise?

Why Superchip... $1500.00 gets a full Haltech system fitted (with closed loop mode).

Timing is (loosely) based on:
a. initial factory settings
b. engine life
c. fuel quality

Other factors like wear in cam/valves etc can alter performance, as can compression loss etc....

I'd suggest a compression test first, working up to checking advance settings on the dizzy and the A/F mix...

My old 3.9 was a shocker! A/F was rubbish factory, changed to a locked distributor and aftermarket and even punching the 5.0L on 35's gave me 17-18l/100km

Good luck in your search!

Tombraider

**byron** · 28th August 2006, 05:49 PM

Originally Posted by tombraider

Why Superchip... $1500.00 gets a full Haltech system fitted (with closed loop mode).

Timing is (loosely) based on:
a. initial factory settings
b. engine life
c. fuel quality

Other factors like wear in cam/valves etc can alter performance, as can compression loss etc....

I'd suggest a compression test first, working up to checking advance settings on the dizzy and the A/F mix...

My old 3.9 was a shocker! A/F was rubbish factory, changed to a locked distributor and aftermarket and even punching the 5.0L on 35's gave me 17-18l/100km

Good luck in your search!

Tombraider

mmmmmm.....you've raised a few more Q's than you've answered. Wot's a Haltech?...a closed loop type ignition/fuel injection system?.....Compression is good in all cylinders [all over 130psi and close to each other], I'm aware of cam wear problems in these if oil isn't chosen and changed religiously [every Sunday, maybe??...lol]...I havent got timing advance factory figures for this year/model 3.9- but comparing to factory recommends for 3.5 and 3.5i up to 1988 they're good!!- max mechanical advance @ 3000rpm[engine] = 28 plus the 6 = 34BTDC...which is close to max I think....altering A/F is what a Superchip will do- not possible to do ATM....these are known to run too rich @ cruise and light loads above 1000rpm, but good @ below 1000rpm and under load and high [>3000] rpm....What's a "locked dizzy"???? and an "aftermarket...." what?????....also wot do u mean by "5.0L on 35's".....sorry bout all the Q's.....but thanks for the input.....BTW....I don't want to spend much on the car....it's a 3rd car only.....doggy walkies mobile/bush basher sorta car!

**p38arover** · 28th August 2006, 08:05 PM

Originally Posted by rangieman

Welcome mate wow what along breath you take

Byron, I don't think you picked up on this comment.

Your posts would be much easier to read if you interspersed a few line feeds rather than creating one very, very long paragraph.

Now I'll go back and try to read it again. I did give up aftetr the first 2 lines.

Ron

tombraider · 28th August 2006, 08:26 PM

Originally Posted by byron

mmmmmm.....you've raised a few more Q's than you've answered. Wot's a Haltech?...a closed loop type ignition/fuel injection system?.....Compression is good in all cylinders [all over 130psi and close to each other], I'm aware of cam wear problems in these if oil isn't chosen and changed religiously [every Sunday, maybe??...lol]...I havent got timing advance factory figures for this year/model 3.9- but comparing to factory recommends for 3.5 and 3.5i up to 1988 they're good!!- max mechanical advance @ 3000rpm[engine] = 28 plus the 6 = 34BTDC...which is close to max I think....altering A/F is what a Superchip will do- not possible to do ATM....these are known to run too rich @ cruise and light loads above 1000rpm, but good @ below 1000rpm and under load and high [>3000] rpm....What's a "locked dizzy"???? and an "aftermarket...." what?????....also wot do u mean by "5.0L on 35's".....sorry bout all the Q's.....but thanks for the input.....BTW....I don't want to spend much on the car....it's a 3rd car only.....doggy walkies mobile/bush basher sorta car!

Haltech http://www.haltech.com.au engine management computers..

Locked distributor - No internal advance

Superchip - Pile of rubbish

5.0L on 35's - 1995 Discovery running a 5 litre stroker and 35" tyres

Bush Bashing - Irresponsible use of a 4wd

LMAO

Tombraider

**DEFENDERZOOK** · 28th August 2006, 08:32 PM

bush bashing = irresponsible........BUT FUN....

**byron** · 28th August 2006, 08:35 PM

Originally Posted by p38arover

Byron, I don't think you picked up on this comment.

Your posts would be much easier to read if you interspersed a few line feeds rather than creating one very, very long paragraph.

Now I'll go back and try to read it again. I did give up aftetr the first 2 lines.

Ron

SORRY!!!!

....

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

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

Huh????....but !!!!......wot??????

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