muddy Posted September 10, 2014 Share Posted September 10, 2014 Evening all, I have some fairly basic, simple even suspension questions. Before I start yes I know I should weigh it but that is not possible right now. 1. If you have a discovery 1 chassis with 50/50 front rear weight distribution and you fit the same springs all round will it sit level front to back or is the chassis higher at the rear or vice versa? 2. I have some fox remote resvoir shocks, these have a schrader valve in the remote part, can I adjust the damping rate by putting standard compressed air in or do I need special tools? 3. With landrover radius arms front and back are very soft springs with firmer dampers any advantage over say 'normal' springs with soft dampers? For slow off roading. ( ignoring any other link system) 4. Does any of that make any sense? Cheers, will. Quote Link to comment Share on other sites More sharing options...
dirtydiesel Posted September 10, 2014 Share Posted September 10, 2014 2) don't use compressed air it's "wet" and will very quickly destroy the inside of the shock, you need nitrogen and a proper valve setup. Quote Link to comment Share on other sites More sharing options...
Cynic-al Posted September 11, 2014 Share Posted September 11, 2014 I'm no expert but... 1. I think the compressed length of standard springs are different front to back so putting the same springs all around with 50 50 weight I don't think it would sit level but it would be easy to double check by crawling under with a tape measure. Also how do you know you have 50 50 weight? 3. This is very situation specific as you have to compare the free length, the spring rate and the weight on that spring but in general if it's a standard land rover I wouldn't go for stiffer springs, it might get higher but will flex less. Soft springs will flex much more. The shocks will control the rate at which the wheel can move. Soft shocks will allow it to bounce which will probably make it unstable. Can you get a shock for a land rover that would be so stiff it will stop the wheel following the ground for slow offroading? Remember if you go for soft springs it will make it less road friendly. 4. Ditto. Quote Link to comment Share on other sites More sharing options...
muddy Posted September 11, 2014 Author Share Posted September 11, 2014 Thanks Dan, I thought I was being hopeful! Quote Link to comment Share on other sites More sharing options...
uninformed Posted September 16, 2014 Share Posted September 16, 2014 even if same springs front and back made it level you dont want same spring rate front and back. Is your rig custom suspenion links or stock. No D1 ever had radius arms in the back. Quote Link to comment Share on other sites More sharing options...
muddy Posted September 16, 2014 Author Share Posted September 16, 2014 Thanks al and uninformed. To outline some more the vehicle is an 88" 300tdi tomcat based on a disco 1 chassis, the engine sits in the standard position very far forward in the chassis although you seem to sit slightly behind the vehicle centre line. It has the tomcat heavy duty axle casings back and front with radius arms all round. It also has fox remote resvoir shocks mounted vertically in the centre of the springs all round. It's has an X9 on the rear and at the moment I've taken the front winch and bumper off but depending on use it may or may not have that also the fuel cell is probably 50litres and behind the rear bulkhead fairly low down. It came with some yellow HD 2" lift springs on and it was horrific to put it mildly and it sat very tall and about 11/2" higher at the rear. I found all my old springs and swapped to D90 fronts 175lb on the rear and this put the rear to a nice height, I then tried disco 2td5 fronts on the front but the drivers side sat too low so I swapped to 5 seat disco 2 rears without isolaters on the front, this had it sitting nice and level and about the right height but the springs would still not compress enough during articulation. I am going to get two NRC4306 16.4" 133lb and two 572315 15.4" 133lb springs and have a play with these as these are the softest is can find, I fear the rear may still be over sprung. My thoughts of stiffer springs is that because the shocks are not long enough to permit dislocation I thought some spring pressure would encourage the RA to flex more as the bushes bind up towards the extremities of travel? If the springs are too soft they may give in before the bushes. I haven't actually driven it off road properly yet just up some walls and over rocks in comparison with my 90 that flexes pretty well. I'm just looking to get it somewhere near so it's useable I can fine tune it from there. Jeez that seems like a lot of bull**** but I hope it makes abit more sense! Will. Quote Link to comment Share on other sites More sharing options...
uninformed Posted September 16, 2014 Share Posted September 16, 2014 stiffer spring to push down on RA means stiffer spring for RA to push up and compress.... Im guessing a truck cab type body? There are a few reasons why you would have a higher spring rate in the rear, espeically coil sprung stock LRs. These include and not limited to: higher rear COG, less roll stiffness in the rear link set up, higher sprung mass.... Since yours eliminates these, Im GUESSING your rears could be closer to the front rate wise. The slower you drive (do you only use it in first low for crawling trials etc??) the closer in rate I guess they would be since you are saying same front and rear mass. Im sure you guys in the UK must be able to get coils custom made at the drop of a hat? I can here in the colonies.... 133lb will be a good start. I know your rig will be light but remember the original RRC was liteish and ran 133lb with good results. Also there is a great deal of importantance between spring rate and shock valving. Play around with springs as best you can till you find a good rate then tune the shocks to suit. btw, take everything I say wth a grain of salt.... just a web wheeler Quote Link to comment Share on other sites More sharing options...
Cynic-al Posted September 16, 2014 Share Posted September 16, 2014 A weight would be handy front and back if you can do it. My bobtail is 1150kg front axle and 875kg rear axle, it has bearmach ba2257 all round which are rears 150lbs +2" lift (although actually give more as the car is lighter), 459mm loa and seems to sit fairly level. If you bought their kit they would send you the ba2256 for the front normally. I was aiming to get longer softer springs as it's offroad only and lighter than standard. I can never understand why people put HD springs on vehicles that they've taken weight out of. Quote Link to comment Share on other sites More sharing options...
muddy Posted September 16, 2014 Author Share Posted September 16, 2014 Interesting. I run 225s all round on my 90 truck cab and that flexs pretty well. I've just ordered the 133's so we'll see how they compare. They are however ****part so they could be anything from 33 to 233lb! Will. Quote Link to comment Share on other sites More sharing options...
landkeeper Posted September 16, 2014 Share Posted September 16, 2014 i'd give them a bell at tomcat motorsport i have found them very helpful in the past with such issues , if your car has radius arms at the rear is it a complete chassis or like some of them two fronts welded together Quote Link to comment Share on other sites More sharing options...
muddy Posted September 16, 2014 Author Share Posted September 16, 2014 It's a complete chassis. I spoke to tomcat at the indoor show, whilst they were very helpful they understandably wouldn't divulge the poundage of their own springs and IIRC they were £45 each, dearer than the four I've just ordered.... At the minuite I don't know if I like the car or it suits my needs so I'm not about to throw lots of money at it. Ill trial it or pay and play it and see how I get on with it and take it from there.... Will. Quote Link to comment Share on other sites More sharing options...
Mudmonkey Posted September 16, 2014 Share Posted September 16, 2014 A friend who's building a trialer spoke to Tomcat and understandably got the same result, think he's resided to the fact that he'll be buying those. Saying that he hasn't touched it all summer so doubt it'll ever get to the stage where it needs springs. Any pics of this new aqusisition Will? Quote Link to comment Share on other sites More sharing options...
Daan Posted September 16, 2014 Share Posted September 16, 2014 I'd go for the deflection at ride height to be the same front and rear, so if your weight distribution front to rear is 60:40, try to reflect this in the spring rates. I would not worry about the ride height just yet; get spring rates to what you like, then adjust the height to suit; either a different spring length or space it out. You can get the sprung weight of the car quite easily, if you measure how much the springs compress and know the rate. I would stay clear of any springs that the supplier don't tell you the rate of; how can you make a comparison if you don't know the rate? Daan Quote Link to comment Share on other sites More sharing options...
ayresy Posted October 3, 2014 Share Posted October 3, 2014 mine has the same springs front and back and the front appears to sit higher ?? 3.9 v8 mounted fairly far back though, thats on 133 springs for trialling flexes brilliantly i would definately reccommend for slower stuff.... not fast corners... ive tried ... it ends upside down remote res shocks and all shocks infact need nitrogen as its inert. Quote Link to comment Share on other sites More sharing options...
Ex Member Posted October 3, 2014 Share Posted October 3, 2014 Yes, when the vehicle is level, the front springs are shorter than the rear. It is a 1.5 to 2" difference. Quote Link to comment Share on other sites More sharing options...
ayresy Posted October 3, 2014 Share Posted October 3, 2014 im not bothered about it being higher at the front as i'm adding a winch and associated kit so it will sit down an inch or so from its current position Quote Link to comment Share on other sites More sharing options...
Team Idris Posted October 4, 2014 Share Posted October 4, 2014 Winches are the worst, as they are in front of the axel, so the suspension goes down by more than the weight of the winch. They actually take a bit of weight off the rear axel ! Mine + associated bits really stops the front from popping up obstacles Quote Link to comment Share on other sites More sharing options...
ayresy Posted October 6, 2014 Share Posted October 6, 2014 Im monting my winch in a custom tray on or part of the front crossmember so should hopefully be as far back as possible. Ill remove it for trials too Quote Link to comment Share on other sites More sharing options...
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