Suspension Lift

So I was out looking under my series 3 tonight. I was looking at the hangers on the springs. Now rightly or wrongly a thought has crossed my mind, :doh: if I wanted to raise the height of the vehicle is it just a matter of fitting longer shackles? Now I have worked out that the shocks wont fit then so is there longer shocks that would fit the series 3 or will a modified mounting bracket need to be made as well. Thats my first question, my second question is how high can i take it ( I was thinking around 4 inches or so ) before I need to start thinking about diff nose angles and drive shaft UJ's? Also will the steering arms need to be replaced?

OK, you cant take it ANYWHERE without thinking about prop nose angles and prop-shaft angles. On an 88 rear prop is too short NOT to.
As for using longer shackles, that IMMEDIETLY twists the diff and screws your diff-nose angle, becouse you are only lifting the back of the spring, rotating it around the spring hanger, twisting the front f#diff down and away from the box, the rear up and towards the box, and putting BOTH prop flanges out of parallel, so you will get drive line shudder from prop imbalence trying to twist the yokes against each other.
You should ONLY use extended shackles with extended hangers...
in the LR catalogue as used on the military 109's and civilian 1-ton.
You have to grind the standard hangers off teh chassis and weld on the longer ones.
THEN you can use the longer shackles, and you get about 2 1/2" lift.
And the prop-flanges stay parallel, so you dont get drive shunt, and the diff angles are... well the nominals are all shifted around, so the diff nose angle's not 'ideal' but not completely screwed.
BUT, the diff sitting lower does mean that the prop at the new ride height is transmitting drive through a more obtuse angle.
Not too bad at rest, but under 'droop' when the axles at full extension, 2" further from teh chassis, it will be close to binding, particularly at the back.
Better option is Paras, which offer about 1-1/2 to 2" lift from longer bow, and thinner spring, so the axle sits firther away from the chassis.
Either on thier own brings the ride hight up to aprox that of a defender, and is 'just' about doable on stanard props, though personally on an 88 I'd be a bit concerned about the back one.
If you want to go higher, 4" ish is do-able with both para's and extended hangers, BUT you would DEFINITELY need wide angle props, and to do the job well, I'd cut the spring saddles off the axle, and re-align them to get something closer to ideal prop-flange angles, for the new nominal range of travel.
With added travel, I'd probably also be contemplating double cordon jointed props to minimise drive line judder and prop vibration.
I'd NOT try and get 4" of lift JUST from shackles, or even shackles and extended hangers.
Both would have to be custom fabricated, and shackles that long would probably have to be tripple re-enforced, while on a stock spring, you would risk 'flatting' it to beyond its bow limit before reaching the limit of axle travel.
However, before you begin, I'd have to quiery where you are startiung and why you'd want to do this?
If you are running stock tyre size, thats a 600 or 205R16. You'd get an inch or more lift going to a 750 or 235/85 LWB size on a wider rim, and ALL that edded clerence would be where its most useful, under the diff pan.
Raising the suspension, lifts the chassis away from the axle, and that is not as helpful for finding clerence. It slightly improves aproach and departure angles, but trade off is it raises the CofG, and the advantage of the lift are usually a lot less than the advantages of keeping teh CofG low.
Look at the comp trials Landies, they keep them low; better CofG makes them more stable on climbs and tilts, and with a little under body protection, clerence is less crucial.
On a leafer, added suspension travel is some justification, but with stock springs, they are just as hard to bend, so you dont get a lot more 'useful' articulation..... hence suggestion that more supple paras are better way to go; the lift they offer gives the travel, and its more easily obtained, and unless you are really pushing the envelope and bashing stuff underneath, probably as much lift as you need, or can use without higher CofG having negative effects that make the car less useful when you aren't bashing stuff.
Personally, I'd keep it low. Bigger wheels are good; lifts not so good.
Protection good; picking your route / line so you dont need it, better.....
Well driven a series with small, considered mods, driven contientiousely will normall get a lot further into places more highly modded motors are struggling.... as proved at my last P&P by a chap in a standard Series One, showing tricked up, 3" lifted disco's etc where to go!

Going the parabolic route to extra lift has a major advantage in that the springs are not as deep as the originals under the axle which gives more clearance under the spring U bolt plates. In my opinion it's the low clearance under the spring plates which are the biggest hinderance to a series vehicle off road compared to a coil sprung vehicle - much more so than the lack of articulation. A 90 on 205 R16s seems to manage ruts just as well as an 88 on 750 R16s in my experience. If you want lift in order to fit some 9.00 x 16 tyres or similar then it might be worth considering doing a body lift, which would not mess up the prop angles.

When I was trialling a Series LR before parabolics came along I used the extended miliatary shackles on the rear to add a slight lift. I have to say that I didn't notice any additional prop shaft vibration, but the UJ nearest the hand brake was always the first to wear out. Not an issue when it is a trials machine tho

Front is more complex and in both cases where it has been done properly the spring seats have been moved to help with prop shaft angles but you still has the castor angle to consider on the front.