o_teunico Posted November 14, 2013 Share Posted November 14, 2013 Hi all, I have heard many times that "full hydro" steering is good because it will enable extreme front axle suspensión upgrades without worrying about "bump steering". Price and road legalities are the cons, but...what about using a beef steering from a 5-6 Ton van with IFS? Iveco Daily, MB Sprinter...could be donnors. Will this steerings work OK connected to standard LR PAS pump or will they need donnor´s one? Steering rack to steering wheel connection will be via a looooooooooooong slip UJ shaft. Quote Link to comment Share on other sites More sharing options...
De Ranged Posted November 14, 2013 Share Posted November 14, 2013 your articulation causes bump steer, so would be surprised if it passed for road legal, better off to look at the new euro cars some of them run full hydro or electric steering ... that is legal so steel that system Unfortunately our rules for modifications are very clear that you need a mechanical connection for the steering....yet these new cars are coming in and driving on our roads... lol hopefully the rules will be updated Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted November 15, 2013 Share Posted November 15, 2013 What DeRanged said - it's the suspension & steering geometry that affect bump steer, fitting a "stronger" box will not change that. I've driven full hydro and although it has its uses I'm fairly sure it's not a good idea in most cases for various reasons - #1 being that if you can't turn the wheel it's because there's an obstruction, so adding more power just means you're creating more stress / likelihood of damage. Quote Link to comment Share on other sites More sharing options...
o_teunico Posted November 15, 2013 Author Share Posted November 15, 2013 Rack and pinion will be fixed directly to axle, so no bump steering if panhard mounts are moddified or A frame, watts linkage or whatever is instaled. What about the pump? Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted November 15, 2013 Share Posted November 15, 2013 So how do you get the steering column down to the axle? Quote Link to comment Share on other sites More sharing options...
elbekko Posted November 15, 2013 Share Posted November 15, 2013 The only way you can get a steering rack on the axle without bump steer is having a vertical steering shaft with a lot of slip... which isn't all that realistic. There are ways to minimize articulation bumpsteer though. With some gearing, if you make it so the steering shaft has to do a lot of turns for little effort, articulation will have very little effect on the steering. Of course this would probably introduce some extra slop into the system, which is probably more than the bumpsteer would've been. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted November 15, 2013 Share Posted November 15, 2013 So how do you get the steering column down to the axle? UJ, sliding joint and attach it to radius arm/link/on-link a-frame? Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted November 15, 2013 Share Posted November 15, 2013 UJ, sliding joint and attach it to radius arm/link/on-link a-frame? Seems like it could get quite convoluted allowing for any decent articulation. I've wondered about this scheme in the past but it never seems like it makes anything any better overall. Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted November 15, 2013 Share Posted November 15, 2013 UJ, sliding joint and attach it to radius arm/link/on-link a-frame?Yes, I have seen such an arrangement on a WW2 Jeep owned by a mechanical engineer many years ago, using a non PS Austin 1800 rack in place of the draglink, not the trackrod, and he claimed it worked perfectly. The rack would be vulnerable to damage on a coiler if the intention was to fit the rack in place of the trackrod. Quote Link to comment Share on other sites More sharing options...
o_teunico Posted November 15, 2013 Author Share Posted November 15, 2013 So how do you get the steering column down to the axle? Upper UJ as standard, bottom one attached to the pinion-rack itself (attached directly to axle), with lots of travel in the slip joint. Real life will show if this is possible or if the "propshaft" will clash with turbo/engine mount/chassis. Ford Pintos used a flexible steering column, something like a super big speedo cable. The rack would be vulnerable to damage on a coiler if the intention was to fit the rack in place of the trackrod Oooops...never thought about that! Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted November 15, 2013 Share Posted November 15, 2013 The Pinto I assume is IFS, so the flexydrive cable sheath isn't constantly changing shape with every little suspension movement, which I'd imagine would quickly fatigue it on a solid axle. IMO your idea would be much easier to package on a vehicle with left hand drive, or a r/h/drive vehicle with the front diff offset to the left side. Yes, I appreciate that Spain is L/H/Drive, but in Spain this idea has little hope of progressing beyond the 'vapour' stage except for closed course competition vehicles. Quote Link to comment Share on other sites More sharing options...
o_teunico Posted November 15, 2013 Author Share Posted November 15, 2013 No Limits kit for the Ford F100... Similar setup for the Chevy truck This kind of setup seems to be really popular among the Hot-Rod community. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted November 15, 2013 Share Posted November 15, 2013 Seems like it could get quite convoluted allowing for any decent articulation. I've wondered about this scheme in the past but it never seems like it makes anything any better overall. Yup, it would be convoluted for sure, but vans with flat fronts like Toyota Hiace's where you sit on top of the wheels have arrangements of UJs that basically turn the steering column through about 180 degrees... So it is possible. Only difference is the slip joint being required, but if you have the UJ on the suspension link it would be minimum in length. I don't think it a particularly good solution though, there must be better ways to do it Quote Link to comment Share on other sites More sharing options...
dirtydiesel Posted November 16, 2013 Share Posted November 16, 2013 I've often thought about using an oversized steering box mounted on the front axle of a buggy, it would take some engineering but i'm pretty certain it could be made to work and give nice feel at speed. But the reality is that fully hydraulic steering is much easier to package, incorperate rear steer and alter ratios. I've driven full hydro and although it has its uses I'm fairly sure it's not a good idea in most cases for various reasons - #1 being that if you can't turn the wheel it's because there's an obstruction, so adding more power just means you're creating more stress / likelihood of damage. Easy solution, Just make sure everything in the system is man sized!! I always found it amusing that i could drive tight up to a rock or wall and the steering force could walk the entire front end off the obsticle, i found it quite usefull a number of times in competions. Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted November 16, 2013 Share Posted November 16, 2013 I don't really see why an oversize steering box would be required, just because its mounting location is now on the axle instead of the chassis. If bump steer is eliminated, then so too are much of the shock loads attempting to shear the pitman shaft, so in actual fact a lighter steering box could theoretically be used. I have never really felt inconvenienced by bump steer at the 1 MPH velocity of my truck when the front axle is articulating through its range of 60 degrees, and feel for coiler owners that more grey matter should be applied to the matter of getting that stupid track rod up off the ground and protected without totally stuffing up ground clearance with half a ton of iron mongery hanging underneath the axle assembly. But that's just me ! There should be a law punishable by tar and feathering, for a vehicle engineer who designs a system where a vital steering component is also the component on the vehicle that is closest to the ground ! And probably a year in the stocks, being regularly pelted with rotten tomatoes is warranted when said engineer applies that system to a supposed offroad vehicle ! Quote Link to comment Share on other sites More sharing options...
o_teunico Posted November 18, 2013 Author Share Posted November 18, 2013 .I don't really see why an oversize steering box would be required, just because its mounting location is now on the axle instead of the chassis I mentioned "beef" thinking about oversized tyres and heavy off-road abuse. more grey matter should be applied to the matter of getting that stupid track rod up off the ground Offset track rod is what you need! Quote Link to comment Share on other sites More sharing options...
dirtydiesel Posted November 18, 2013 Share Posted November 18, 2013 I can see almost no gain in that track rod setup, the rod is still just as vunerable over 2/3rds its length, Quote Link to comment Share on other sites More sharing options...
De Ranged Posted November 18, 2013 Share Posted November 18, 2013 I mentioned "beef" thinking about oversized tyres and heavy off-road abuse. No these arnt issues if your scrub radius is small.... you need that "beef" when you run oversized tyres with offset for more width this increases the scrub radius which means more leverage on the steering system I'm with bill on this, steering linkages down low is just lazy and it was one of the things I wanted to change with mine Nice idea for the tie-rod but that is something we arnt allowed on road here lol, and for offroad na lol it'll still get caught... notice all the missing paint on the underside of the axle higher than where the new tie rod is.... Quote Link to comment Share on other sites More sharing options...
dirtydiesel Posted November 18, 2013 Share Posted November 18, 2013 I don't really see why an oversize steering box would be required, just because its mounting location is now on the axle instead of the chassis. If bump steer is eliminated, then so too are much of the shock loads attempting to shear the pitman shaft, so in actual fact a lighter steering box could theoretically be used. I was considering a 7.5ton truck steering box so i could still turn 40's with one finger but i wouldn't need new pants to drive in traffic, Even with 15degrees of caster my hydro steer wouldn't self center quick enough at road speeds, Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted November 18, 2013 Share Posted November 18, 2013 Easy solution, Just make sure everything in the system is man sized!! I think this is our North/South difference of philosophies in action Teunico - hot rods aren't really known for their articulation are they? Normal steering works fine on normal cars with normal articulation... Quote Link to comment Share on other sites More sharing options...
o_teunico Posted November 18, 2013 Author Share Posted November 18, 2013 No these arnt issues if your scrub radius is small.... you need that "beef" when you run oversized tyres with offset for more width this increases the scrub radius which means more leverage on the steering system The Disco I have pre-bought has offset modulars and I will like to fit (with correct gearing/halfshafts) some 35-36" tyres whith wheel spacers. steering linkages down low is just lazy and it was one of the things I wanted to change with mine Maybe some series ones could be adapted, but in a coiler the panhard rod will be in the way. Quote Link to comment Share on other sites More sharing options...
o_teunico Posted November 18, 2013 Author Share Posted November 18, 2013 Another alternative: track rod is eliminated. Right of the axle is form LHD vehicle and left is from a RHD one (I think that later Defenders are built that way, with same axle for LHD and RHD). Rack and pinion will be located up in the front of the axle, in place of draw bar. Steering damper will need a rearangement, and maybe panhard too. Quote Link to comment Share on other sites More sharing options...
Gremlin Posted November 18, 2013 Share Posted November 18, 2013 Its not worth the effort to have a weak R&P down at the axle!! Just go back and rethink this super hard. As to bumpsteer, look at the old US baja race trucks, they mounted the box where the suspension pickups are at the chassis, and ran a fore and aft arrangement similar to a series, but with no relay, and steering box at chassis level. Hard to explain, but you might figure it out. Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted November 18, 2013 Share Posted November 18, 2013 The Disco I have pre-bought has offset modulars and I will like to fit (with correct gearing/halfshafts) some 35-36" tyres whith wheel spacers. Maybe some series ones could be adapted, but in a coiler the panhard rod will be in the way. If uprating front halfshafts to 24/23 spline, then grafting Series Stage One V8 Birfield jointed swivels balls to coiler axles is not that difficult, and if you use Santana outer swivel housings, they already have provision for disc brakes. On WildFing I raised the Panhard rod chassis and axle mounting points higher to provide clearance from the trackrod at full bump. I also mounted the Toyota Steering box higher so that the draglink and Panhard rod were quite parallel. Steering box relocation is a little more difficult on genuine coilers, but still do able. I'd rather see someone design bolt on steering arms for coiler axles that put the trackrod up front, and maintain Ackerman angles for those that are concerned about such things. Quote Link to comment Share on other sites More sharing options...
dirtydiesel Posted November 20, 2013 Share Posted November 20, 2013 How about this for an alternative setup O_teunico? Quote Link to comment Share on other sites More sharing options...
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