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EVdV



Member Since: 26 Nov 2017
Location: Vosselaar
Posts: 53

Belgium 2006 Defender 90 Td5 ST Java Black
Suspension lift theories
I was thinking about optimising my 90 td5 a bit for the roadbooks and playgrounds I visit, which got me thinking about suspension lifts and their (limited) advantages.
Fitting bigger tyres is an obvious advantage offroad, and lifting the car to accomodate these is advised everywhere, but is that theory right?
Maximum upward travel is limited by bump stops. Maximum downward travel is limited by the shocks. Springs that lift the body are almost always combined with longer shocks, which give more downward movement and so is an unquestionable plus offroad. But the lift springs itself just let the body sit higher in the suspension travel, they do not limit upward travel (unless the springs are binding), so the bigger tyres come as close to your body/chassis components as a non-lifted vehicle. The tyres might get there less often, but any clearance issues would be there in both cases, or am I missing something?

Of course the departure and breakover angles increase a bit, but is that worth the hassle of cranked radius arms, trailing arms, binding/vibrating propshafts etc?
My mate has a 3' lifted long wheel base rubicon, which constantly gets hung up due to these angles, where I pass without problems in my standard little 90 Rolling Eyes , so increasing these angles is none of my priority's. Larger circumference tyres and longer shocks seems a far better choice then spend a lot of money on arms, propshafts etc.
(Plus finding suitable springs for a light 90 soft top which don't make it even more bouncy is not easy.)
Post #800108 30th Oct 2019 7:32pm
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jst



Member Since: 14 Jan 2008
Location: Taunton
Posts: 8050

 2011 Defender 110 Puma 2.4 USW Stornoway Grey
taller springs means the body is higher so the larger wheels have more upward travel. upwards travel needs to be limited by bump stops not coil bound springs or shocks topping out.

Lift it 2" and add +2 " travel springs and the shock still have same travel (as std setup) up or down from same axle height (assuming tyres height not changed). it just allows shock to maintain the same downward travel and 'reach' its top mount which is 2" higher than prior.

to maximise may need +5" shocks to increase downward travel but essential to ensure upward is limited by bump stop and not shock topping out.

cranked arms help steering angles on the front and reduce bush wear on the rear but are not essential.

larger UJs may be needed is suspension travel is increased to ensure UJs dont bind on full articulation.

longer brake pipes should be fitted to front. rear will prob work fine with std flexi assuming its at top of A frame. Cheers

James
110 2012 XS Utility
130 2011 M57 bespoke Camper
90 2010 Hardtop
90 M57 1988 Hardtop
Post #800124 30th Oct 2019 9:25pm
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sako243



Member Since: 08 Jul 2014
Location: Wales
Posts: 1222

Wales 1994 Defender 110 300 Tdi CSW Alpine White
What kind of terrain are you usually covering?

I've not personally (at least knowingly) driven a lifted vehicle but been in groups where there have been plenty and covered all sorts of terrain from Scottish peat bogs through to large rock climbs in the south of France. I've usually had less of an issue crossing the terrain than the lifted vehicles. Part of that I suspect is experience and in picking a different line where necessary but recently I've fitted two lockers to the front and rear axles and that has utterly transformed it off-road and lifted vehicles and as it's an everyday vehicle as well as a play toy I wouldn't want to fit a lift kit. I haven't even bothered disconnecting the anti-roll bar. Even just having one locker fitted made a huge difference but two basically means I'm going in a straight line whether I like it or not.

Fitting a lift kit and bigger tyres is probably cheaper, but maybe not that much in it. I think my rear locker cost about £1.5k all in but it was the first I did so that included air compressor and also sourcing a short nose 110 rear axle to replace my Salisbury. The front was about the £1k mark (note these are both pegged with new bearings and HD internals and new Ashcroft halfshafts and drive flanges). But having said that if I were to go to taller tyres then getting bigger BFG Muds there wouldn't be much change from £1k if I included a spare, then you've got to factor in all the other bits that jst has mentioned like dampers and brake hoses etc.

So just providing food for thought... I personally wouldn't want a lifted vehicle and much prefer the flexibility a locker gives me but each to their own. Ed
82 Hotspur Sandringham 6x6
95 Defender 110 300Tdi
Post #800127 30th Oct 2019 9:43pm
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EVdV



Member Since: 26 Nov 2017
Location: Vosselaar
Posts: 53

Belgium 2006 Defender 90 Td5 ST Java Black
Jst, completly agree, more travel thanks to the shock being longer, and the lift spring to have the body in the correct height within that travel. But it is commonly said that you need the lift to accomodate the lager wheels, which actually is not true, unless you limit the upward travel with bump stop spacers (not a good thing). Wheels touch components regardless of ride height, 0 or 5 inch lift, if the bumpstops stay the same, the distance from hub to body/springs etc (thus tyre clearance) stays the same.

In that mindset, larger tyres and longer shocks is a smarter buy to start with and will get you far offroad for a much smaller budget.
Or am I missing something Whistle
Post #800129 30th Oct 2019 9:44pm
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EVdV



Member Since: 26 Nov 2017
Location: Vosselaar
Posts: 53

Belgium 2006 Defender 90 Td5 ST Java Black
Sako, I'm not that keen to lift it either, thats why I started the topic. A lot of local salesmen advise to lift with all extra parts that come with it, but the occasions where I proboably would have needed a lift to get through without winching are very scarce.
Larger circumference tires would make a bigger difference, so i would like to fit them combined with some quality shocks to smoothen the ride a bit.
I don't drive it much (6000km/year) and allmost all of them are on road, but when its offroad, it's no average greenlane. Axle twisters, tight technical forest sections, trip to Marcanterra every year...

At the moment it has standard suspension, winch bumper with winch, tree sliders, et0 16x8 wheels and 265/75 bfg all terrains (which are out of round so need to be replaced).
I would like to go to 285/75 km3's or 255/85 toyo mt's and fox +3' shocks.
Post #800134 30th Oct 2019 10:01pm
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jst



Member Since: 14 Jan 2008
Location: Taunton
Posts: 8050

 2011 Defender 110 Puma 2.4 USW Stornoway Grey
bigger (taller) tires will contact body work quicker on std height springs over smaller tyres.

bigger tyres means longer bumpstops to stop the contact for given std spring height.

to maintain upward movement you need to increase body height and possibly increase bumpstop height/length depending on setup of tyres/springs etc.

also consider contact on full bump one side and wheel on full lock with taller tyre.

you can go to the tyre size you state (33s) quite happily on std height springs and not worry. just check your +3 shocks don't top out before the bumpstop. check they compressed length over angle acting compared to axle full bump both and single sides. youw il get some lateral axle movement in the arc on front. best way to check is articulate it through full movement with tyres on but no springs fitted using jacks. Cheers

James
110 2012 XS Utility
130 2011 M57 bespoke Camper
90 2010 Hardtop
90 M57 1988 Hardtop
Post #800137 30th Oct 2019 10:17pm
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sako243



Member Since: 08 Jul 2014
Location: Wales
Posts: 1222

Wales 1994 Defender 110 300 Tdi CSW Alpine White
So I'm running stock suspension on my 110 (gone back to standard station wagon progressive springs front and rear and koni dampers) with rear anti roll bar and on 265/75R16 KM2s and never really suffered ground clearance issues. The fact you mentioned axle twisters makes me think a locker (or two) if you don't want to lift it would make more sense. With mine the 110 can easily cock a leg so to speak and carry on through. Some of the ditches etc in Scotland I've crossed you'd need stupid lift in order to keep the wheels on the ground. With the lockers simply lock them take the ditch at the correct angle and doesn't matter how deep it is you still have three wheels being driven.

In terms of comfort on the road, sorry your best bet is get a 110 Laughing. My sister had a 90 and always found them to be very bouncy. I've hosted two trips in Wales recently and went to Seven Sisters last year with where I did the night stages with a Jimny, on all occasions we found my 110 which is running Zus could out turn the 90s and wasn't far behind the Jimny. I have no idea what offset they are but all I know is that since fitting them on the 265s my turning circle is amazing.

I, personally, having offroaded an 88", 90, 110 (ignoring the P38 and L322 for the moment) actually much prefer the 110, the extra wheelbase I find keeps traction for longer and is much more stable. With the Zus compared to most 90s there's almost no discernible difference in tight spots. Admittedly I suspect a 90 with Zus would be better but hey.

With regards to comfort if you have a station wagon or can remove the bulkhead then you could always do what I did and fit some seats out of an L322. Now you're talking comfort. Who cares about stiff suspension then! Bonus is they're cheaper than XS seats but there are a few complications with fitting (which I can describe).


Click image to enlarge
 Ed
82 Hotspur Sandringham 6x6
95 Defender 110 300Tdi
Post #800138 30th Oct 2019 10:21pm
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jst



Member Since: 14 Jan 2008
Location: Taunton
Posts: 8050

 2011 Defender 110 Puma 2.4 USW Stornoway Grey
The only real advantage to a lift is improved approach angles and ability to run larger tyres with more up travel particularly on lock and bump.

A locker is by far the best solution for improved traction, you dont need travel as .much for traction , but it does help stability.

On question of wheelbase we have actually gone to 118" and 122" on for greater stability off road at speed and security on climbs. For tight woodland work a short wheelbase is generally more manageable. Cheers

James
110 2012 XS Utility
130 2011 M57 bespoke Camper
90 2010 Hardtop
90 M57 1988 Hardtop
Post #800173 31st Oct 2019 10:19am
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EVdV



Member Since: 26 Nov 2017
Location: Vosselaar
Posts: 53

Belgium 2006 Defender 90 Td5 ST Java Black
I just bought a second defender last week, 110 dcpu td4, so I'm keen to feel the difference. It must be quite some high speed runs you do ,and lengthen the wheelbase to sabilise it, some sort of rally raid?
I come from a motorcyle (racing) background and wish I had the same adjustability in my suspension, but the prices for decent adjustable materials are eyewatering (and everything 4 times).

Fitting long travel suspension, bumpstops, arms etc (on a defender that already has lockers and decent tyres), must be close to a competition/trial ready vehicle in the right hands?

Lockers is indeed the upgrade that would bring me further in many circumstances, aside from tire size/type. Extra travel would come in handy, but TC often helps me through the axle twisters and tight forest sections.
Post #800236 31st Oct 2019 7:42pm
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jst



Member Since: 14 Jan 2008
Location: Taunton
Posts: 8050

 2011 Defender 110 Puma 2.4 USW Stornoway Grey
TC is reactive is the slight compromise with it, you loose time, momentum and power with its actuation. Lockers prevent the loss of momentum in first place.

Suspension comes at a cost. around £3.5k a corner i believe on the last car i codrove in. King of events, Croatia trophy that sort of stuff. Cheers

James
110 2012 XS Utility
130 2011 M57 bespoke Camper
90 2010 Hardtop
90 M57 1988 Hardtop
Post #800243 31st Oct 2019 7:57pm
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jst



Member Since: 14 Jan 2008
Location: Taunton
Posts: 8050

 2011 Defender 110 Puma 2.4 USW Stornoway Grey
these events: https://www.youtube.com/watch?v=5rhFotn-Wu...y7iS4mTqlL Cheers

James
110 2012 XS Utility
130 2011 M57 bespoke Camper
90 2010 Hardtop
90 M57 1988 Hardtop
Post #800248 31st Oct 2019 8:08pm
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Markez79



Member Since: 27 Jun 2018
Location: South West
Posts: 201

For those that have fitted lockers on a Puma, have you also fit a switch to cut off the TC when the lockers are engaged? I read on the forum that TC and lockers wouldn't work together.

Thanks
Post #800318 1st Nov 2019 11:53am
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jst



Member Since: 14 Jan 2008
Location: Taunton
Posts: 8050

 2011 Defender 110 Puma 2.4 USW Stornoway Grey
You are correct, they dont work together on the same axle.

If you have a locker in both wheels on that axle turn at the same speed so Tc doesn't have anything to do on that axle.

If you have a rear locker in and cdl then both rear wheels and one front wheel are guaranteed to receive drive. Tc would work on the front axle which is no bad thing.

You certainly dont need any switch. Cheers

James
110 2012 XS Utility
130 2011 M57 bespoke Camper
90 2010 Hardtop
90 M57 1988 Hardtop
Post #800408 1st Nov 2019 9:27pm
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