1994 Disco Series 1 and 3.9V8 questions

[Shark]

Well just spent the last three hours going through all the old threads seeing if i can get some questions answered but i seem to have come up short.

I have a S1 Disco with the 3.9 standard engine and one of my questions was what is a safe RPM to take these engine to?? I wanna have som fun but i dont want to kill it.

Also has anyone actually done some reasonably simply power upgrades to this engine?? I dont want to stuff around with exchange engine nor do i want to put a stroker kit through it. I know about free flowing exhausts and the like but i want something a little more.. Its not too bad on gas and a little better on petrol but i really want it to blow off the idiot holden drivers around here Anyone bolted on a turbo or a supercharger??

Also without putting too much strain on the drive train what size tyres are a good size without going over board that make the car look like a 4wheeldrive and help lift those diff pumpkins up and what kind of mods do i need to do to achieve this. Its shocking offroad...drags its arse everywhere!!!

My powersteering is leaking and it seems to be coming from where the pipes go onto the top bottle...so i removed the pipes and cleaned everything up..cut a small section of the old pipe off and used new clamps but it still seems to be weeping from where they join onto the filler bottle...im assuming these are the original pipes so should i just order in some new ones??

And last but not least is to take the steering wheel off do i remove the horn button with a large screwdriver ( Prise it 0ff??) and then unbolt it??

Thanks fellas

Marc

[stuee]

In regard to rpm, when I was last speaking to the landy specialist he was telling me theres no limiter so, so when tuning them they reved the engine untill the valves started bouncing took off a couple hundred rpm and set a rev limiter there. I've had min up to 5500rpm before for breif periods and when on the sand trying to do some of the bigger climbs it often sees just over 4500rpm for a fair amount of time. I wouldn't be to keen to take it much further than 5500, mainly because it doesn't do much more over this except make more noise and you can really feel it struggle to breath at such high revs.

For upping power, apart from an exhaust and tune I really stuggle to see why people waste their money improving the rover motors. The $/hp value seems quite low when you compare it to most other makes. By the time you supercharge it you're already half way to spending the same amount for an engine swap. The only improvement i consider when keeping rover is to drop in a 4.6l short block and even that will set you back $$$ if you can't do it yourself.

I wanna fit 33s to my disco but to get these fitted costs a fair bit with all the mods you need. There is actally a fair bit on tyres on here if you look but from what I gather the minimum you need to do to get 33s is a gard chop, backspaced wheels (not sure of backspacing exactly but tht means getting rid of my freestyle alloys ), and either a 2" body lift or suspension lift. When I do it I'm going to try without the lift as I'm really quite happy with its height now.

[up2nogood]

Bigger tyres are going to mean diff and axle breakages and there's another $3-4k to spend on JacMac or MaxiDrive upgrades.....

Engine wise, it looks like a 4.6 conversion is a cheaper option than forced induction, although either option is going to lead to stock ECU dramas, so there goes more money......

And I think these engines produce max torque around 4k RPM, so revving harder than that is a bit of a waste. These lumps are never going to catch up with V8 sedans without having about $15-$20 spent on them. They are just too heavy.

[justinC]

Just to addto the forced induction thread...
I had a naturally asp 4.7 high compression stroker in my rangie,with upgraded ECU and HM headers ,2.5" system ,port matched heads, longer intake ram tubes , high lift cam, etc etc etc, and after driving a blown 3.9 Disco that one of my customers had, I would say the 4.7 had it over in every rev range. AND I was running 11.50 33 tyres, he had stock alloys and 235/70/16's. Even after I replaced the cam in his with the same as mine etc, mine would eat it for breakfast....AND He used more fuel!!!
Go the cubic inch increase, a 4.6 short will bolt straight in, is marginally more $ than a full and proper rebuild for your 3.9, and an upgraded ECU from Bruce Davis to suit is only around $650, and all you have to do is just plug it in! The last one I did ended up using less fuel for towing, (Manual box) because he could take hills in 4th instead of 3rd.


PM if you need more convincing!!

JC

[Shark]

Yeah i figured it would turn into a huge money pit if i started mucking around with all of that stuff so i will more than likely keep it the same.

What size tyres are a common size for everyone to upgrade to?? I dont mind the guard chop or the suspesion lift but i dont wanna body lift or to go too crazy but i want it to look good without comprising the power too much.

And anyone know about the steering wheel?? Mines not centre and i wanna fix it??


marc

[justinC]

you can goto 245/75/16 with the guard chop and 2" lift, no body lift. This will give you good diff clearance without too much of a gearing issue. If you want to go to 33" tyres, you really should go up to a 3" lift and try the defender transfer gearing, but the body roll etc becomes too much of a pain and diff nose angles become too much, vibrations are shocking. Also steering becomes an issue so slotting the swivels is a good idea to retain some caster!!!
The steering wheel can be centred by adjusting the length of the primary drag link, the one from the steering drop arm to the left swivel housing.

JC

[TRobbo]

This thread has some very good info about performance upgrade (thanks to PhilipA)

http://www.outerlimits4x4.com/PHP_Modul ... hlight=4+6

[Philip A]

Yeah, I climbed Mt Ousley yesterday with about 200Kg of camping equipment in top gear all the way. As the limit is 80 KMh the car was alternating between lock up and no lock up, and will Juuuust not pull it in lock up. Although i didn't really find out as it was a double demerit weekend.

Mt Ousley is the climb out of Wollongong toward Sydney and is a STEEP long climb notorious for testing cooling systems.

I am very happy with my car now. I have just bought a set of 205x16 BFG Long Trails for road use and keep a set of 245.75x16 for muddy stuff.
Reason is to drop that gearing by 6% so that I can climb the big hills. Before you laugh the Long Trails are assymetric and give really sharp cornering as they have a very solid outside shoulder. The inside shoulder however is like an AT. I find that rangies like narrow tyres with less steering kickback etc. Not fashionable though. However I am an old fart now.


My rear main seal has just decided to become an underbody spray lube so I guess I will let a workshop do this one. Not into wrestling transmissions any more.
regards Philip A

[oldzook]

And anyone know about the steering wheel?? Mines not centre and i wanna fix it??


marc

fine tune your steering at the draglink from the pitman arm across to left wheel. one TRE is LH thread & other is RH thread, so when you turn the draglink tube you realign wheels with the steering box at centre position.
you'll probably also have noticed you have more lock one way than the other.

cheers
Dan