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Bob uk
Unregistered guest
Posted From: 94.197.122.71
Posted on Tuesday, 16 September, 2014 - 11:06 am:   Edit PostDelete PostView Post/Check IP

I have driven a few vans with air suspension on the rear.
And have been impressed with the ride.

The system in the LDV 3.5 ton vans has a little electric compressor that charges up a gallon tank at 200 psi ( I think not sure) the compressor is wired to the alternator via a relay so that the compressor only works when the engine is running.

The system will last a week when vehicle isn't used. It takes about 3 mins for the van to level. When in use the system is automatic with no driver controls. The bits are all under the van. With the compressor low down in the engine area. They never give trouble and you wouldn't even know it's there. I did have an air height valve jam once but a quick WD40 and a wiggle fixed it.

There is a similar system that has no compressor and has Schrader valves for a garage air line. Like pumping up the tyres. They hold air for about 2 months then need a top up. Unfortunately a cigar lighter electric compressor won't have the puff to top up.

I personally think the SY rear levelling system is over complicated and doesn't really work that well fortunately for me my car apart from needing new hoses works as it should. Even the rubber boots on the links are prefect.( moisturizing them with red rubber grease keeps them supple)

Air bags are gas springs and completely replace the coil spring dampers and leveling ram.

The air springs will lift easily 1 ton each.

So if you have a shadow with bad springs, dead dampers, disabled ride because it's leaking or bits even completely missing.Then the air bag would be a cheap option.

Air springs come in all shapes and sizes and some look like telescopic dampers but fatter and made of rubber ( probably synthetic super duper NASA spin off with Dunlop, DuPont and GM thrown in for good measure).
They cost around £130 each.
The vary from 3" long at 0 psi to 9" long fully inflated. A stroke of 6". Off roaders have lots more stroke. The idea is that a strut is added to get the length right a longer strut means less pressure and soft, a short strut means more pressure and a firmer ride. Adjustable strut length such as a screw Jack in place of the ram would work to get the spring rate just right plus should one want to go racing then it can quickly be altered.
A 2" thick round plate with a 2" dia screw threaded through it and lock nut in place of the ram using the 3 bolt holes is ideal.

Compressors are available second hand. Range Rover ones are sought after used because they are £500 new and £250 exchange. This fit inside the spare wheel. Not sure but I think it has a tank integral with it. The LDV one is about £50 used. And also if going this route get the height valves to fit where the hydraulic ones were fitted.

The pipes are nylon with simple push fittings.

The system can also be used at the front.

There are kits for popular cars. The classic mini one has user operated controls so the car can be slammed and then lifted when speed humps or pot holes appear. Cheaper versions have a couple of hand valves in the boot.

These systems are so tweak able. For instance if an additional small reservoir is connected via a solenoid valve to an air spring then the extra volume will soften the spring and the height valve will add air to level the car. The combinations are endless and simple to do and cheap once installed.

However if this route is taken then do keep the bits removed and don't chop the the springs turrets about. And it is changing the favour of a RR which although IMO flawed in the rear levelling department does work and like my car be reliable. I have driven a few SZ cars and they are better at the back than an SY.

The reservoir could be a length of 3" steel gas pipe cap at one end and a 3" to 3/8 adaptor at the other. Any heating engineer should be able to make one in 30 mins. So cheap.

(Message approved by david_gore)
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Chris Miller
Prolific User
Username: cjm51213

Post Number: 248
Registered: 5-2013
Posted on Wednesday, 17 September, 2014 - 12:25 am:   Edit PostDelete PostView Post/Check IP

Hi Bob,

This is a bit off-topic, but tangentially related; is is a compressed air topic.

On the '71 and '72 shadows, which in my case are both LHD, the accumulators and the steering consume the space on the left side of the engine, but the right side of the engine is largely unencumbered. I want to put an air horn there. (-: Yes. Like a truck air horn. Big. Loud. Surprising.

This seems like a modification that would be right up your alley. Ever do anything like this?

Chris.

P.S. Why don't you have a registered profile? It is impossible to send you a message without it. Send me your e-mail address.
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Brian Vogel
Grand Master
Username: guyslp

Post Number: 1042
Registered: 6-2009
Posted on Wednesday, 17 September, 2014 - 12:47 am:   Edit PostDelete PostView Post/Check IP

Chris,

From prior reading here and elsewhere air horns were originally fitted for certain markets (or else as an an option). The first time I saw this mentioned I asked myself, "What earthly reason would one have to use this?" [I still ask myself that question.]

Air horns are mentioned in Tee-One Topics issues 8, 57, 67, & 73, but I haven't explored in precisely what way.

Brian
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Chris Miller
Prolific User
Username: cjm51213

Post Number: 249
Registered: 5-2013
Posted on Wednesday, 17 September, 2014 - 12:55 am:   Edit PostDelete PostView Post/Check IP

Hi Brian,

So, I'm not the first guy to think of this...

Why? Well, in my case, because I think it would be a huge surprise to have a Rolls Royce sound like a truck, and I think that surprise would be fun. There is something very "untruckish" about a Rolls Royce, but an air-horn is unmistakably "truckish".

Trucks have the option to use the air horn or the "normal" horn, so I'd keep that behavior, but if I really wanted to be heard, the air horn would be pretty fun.

Chris.
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Brian Vogel
Grand Master
Username: guyslp

Post Number: 1043
Registered: 6-2009
Posted on Wednesday, 17 September, 2014 - 01:38 am:   Edit PostDelete PostView Post/Check IP

Chris,

See this thread in the Archive Section for a conversation regarding air horns (of the noise-making type, not air-intake type) on the Shadow series cars.

If you search the forums for FIAMM (one of the brands) you'll also find a discussion regarding SZs and air horns.

Brian
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Bob uk
Unregistered guest
Posted From: 94.197.122.84
Posted on Wednesday, 17 September, 2014 - 05:10 am:   Edit PostDelete PostView Post/Check IP

Error in my air ride posting.

Larger volume of air in the bag means softer ride. Smaller volume means harder.

I put it a#se about face.

(Message approved by david_gore)
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Bob uk
Unregistered guest
Posted From: 94.197.122.84
Posted on Wednesday, 17 September, 2014 - 05:04 am:   Edit PostDelete PostView Post/Check IP

Best place for air horns is under l/h front wing behind the front wheel. The radio aerial is on the r/h front wing.

(Message approved by david_gore)
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David Gore
Moderator
Username: david_gore

Post Number: 1470
Registered: 4-2003
Posted on Wednesday, 17 September, 2014 - 08:20 am:   Edit PostDelete PostView Post/Check IP

DRH14434 was fitted with FIAMM "Continental" air horns at the factory - the compressor was on the rear LHS guard near the hydraulic reservoir above the heater tap and the horns were behind the front bumper bar on the LHS. They were positioned to slope downwards to drain any water from road splash that entered the trumpets. I suggest this is a better location than being in the wheel wheel to minimise water corroding the trumpet internals. The air horns were operated by a foot switch mounted high up on the firewall to the right of the headlight dip switch.

The Fiamm units were the original triple trumpet units with enough volume to outdo Arch-Angel Gabriel let alone wake the dead!!! Just the thing to get the pesky Continentals [and Australian Sunday drivers] out of the way......
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Bob Reynolds
Prolific User
Username: bobreynolds

Post Number: 156
Registered: 8-2012
Posted on Wednesday, 17 September, 2014 - 08:40 pm:   Edit PostDelete PostView Post/Check IP

In my young and carefree days, before I grew up, I put 2 of those triple trumpet units on the front grille of my Mini. That's 6 horns.

I once blasted some bloke in front of me who had just cut me up, and he visibly jumped up out of his seat and hit his head on the roof!

Now - I can't remember the last time I used the horn button; and I don't think I've ever used it on the Rolls Royce.
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Bob uk
Unregistered guest
Posted From: 94.197.122.78
Posted on Wednesday, 17 September, 2014 - 09:39 am:   Edit PostDelete PostView Post/Check IP

Good point about corrosion Dave because the pump does need maintenance or they seize. And the under wing position would make that awkward. My electric horns are quite loud.
Do you remember wolf whistles.

ZF Sachs are developing a nevomat self leveling damper that has a small remote electrical hydraulic pump that immediately levels the car then when moving the pump inside driven by the movement of the suspension takes over.

Monroe do air max dampers that have remote Schrader valves to level. Which are about £50 each which sounds too cheap to me.

Nevomats are very expensive and the extra of an electric pump will probably push towards a £1000 pair and that may be enough fix a SY ride system as RR intended. And the nevomats would have to be modified. Not for the faint hearted.

(Message approved by david_gore)
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Brian Vogel
Grand Master
Username: guyslp

Post Number: 1047
Registered: 6-2009
Posted on Thursday, 18 September, 2014 - 12:35 am:   Edit PostDelete PostView Post/Check IP

Bob,

Air leveling using shocks/struts/dampers (take your pick of term) with an air bladder near the top have been common on higher-end American cars in several cycles now.

I have a 1989 Cadillac Sedan de Ville that's my daily driver and it has an air leveling system with the electronic equivalent of the height control valve attached to the car very similarly to the SY setup. The compressor is in the engine compartment. Another friend who's got a 1993 Turbo R is keeping his wife's 1991 Lincoln's pneumatic leveling system going as well.

I just replaced the rear struts with long defunct (from dry rot) air bladders on this car shortly after I bought it (with Gabriel G56906 Ready-Mounts). The system works like a charm so long as the bladders are intact, the compressor works, and the little O-rings at the various fittings are still holding a decent, if not perfect, seal. The bits of the system other than the air bladders are all working just fine.

It would be conceivably possible to fit something like this to an SY, but I can't really imagine an earthly reason to do so. I'd rather fix the original or blank off the original and do without.

Brian
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Bob uk
Unregistered guest
Posted From: 94.197.122.74
Posted on Thursday, 18 September, 2014 - 06:12 am:   Edit PostDelete PostView Post/Check IP

The problem with just blanking off is that when loaded the car will sag at the back.
Fitting up rated springs might ruin the ride. Plus the rear joints on the drive shafts may not like the jaunty angle. Air springs have a long life if maintained correctly. Air leaks tend to overwork the compressor.
I had no problems with the LDV air system
Some of the LDV had cart springs only and until one drives both versions back to front does one realise how good air ride is.
the cart spring version unloaded rode like a gun carriage and when loaded wallowed about.

(Message approved by david_gore)
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gordon le feuvre
Experienced User
Username: triumph

Post Number: 49
Registered: 7-2012
Posted on Friday, 19 September, 2014 - 02:53 pm:   Edit PostDelete PostView Post/Check IP

fiamm air horns were a factory option, fitted in the positions exactly as described by David Gore down to the push button to operate being next to floor mounted dip switch
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Richard Treacy
Grand Master
Username: richard_treacy

Post Number: 3083
Registered: 4-2003
Posted on Saturday, 20 September, 2014 - 12:26 am:   Edit PostDelete PostView Post/Check IP

As we all know, Fiamms are standard equipment on most SZ cars. The changeover switch to select the sombre electric horns or the dual air horns is on the console. The steering wheel buttons activate each depending on what is selected on the console. Tomorrow I must flick the switch to check that the boring ones still work as the air horns are de rigueur.

.
The air horns are mounted under the LH valence near the bumper. The air pump is located at the scuttle on early SZ cars and by the cooling system expansion bottle on later cars. It needs a squirt of sewing machine oil into its oil reservoir yearly otherwise the air horns will sound like a raspberry rather than a scream. As the pump lubrication may not be specified in some service schedules, a raspberry flavoured air horn may indicate an inexperienced service outlet.

As to air suspension. Lovely stuff, and Conti GTs and Flying Spurs adore it. Pity about $8,000 for a pair of new struts on the front every six years when they fail.

RT.
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Bob uk
Unregistered guest
Posted From: 94.197.122.77
Posted on Saturday, 20 September, 2014 - 07:39 am:   Edit PostDelete PostView Post/Check IP

That's terrible only 6 years and £5000. 6 years is like a service item. Surely the after market air spring makers could sort it out for £500. Even truck ones aren't as expensive.

While reading about air ride kits. A seller of kits includes in the kit an envelope which says do not open. Inside are the instructions. Because 99% of problems is caused by incorrect fitting of the kit.

My interest in air is that it's wide range of easy to do settings. On coil and damper the coil rate is fixed which means the damper settings are fixed. Adjustable dampers help but the spring rate is the real comfort influencer.

(Message approved by david_gore)
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Richard Treacy
Grand Master
Username: richard_treacy

Post Number: 3084
Registered: 4-2003
Posted on Saturday, 20 September, 2014 - 09:27 pm:   Edit PostDelete PostView Post/Check IP

Conti GT air spring struts. Sure, 6 years is almost the same as the life of a lowly cheap and disposable SZ gas spring or an SY brake accumulator at less than a thousand quid all-in for the lot fitted. OK for an ACCU but lousy for a Conti GT air spring strut. There are refurbished struts on offer now for less, maybe GBP1000 exchange with promises of long life, but that is to be seen given the poor life of the originals out there. That may drop the bill to half, but on a GT it will still be at least $5000 just for the strut exchange all-in without any routine servicing done at the same time. Some hopefuls may save a few quid compromising along those lines. Mind you, 6 years seems to be pretty much the median given the thousands of air struts that Crewe is presently selling each year.

RT.
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Bob uk
Unregistered guest
Posted From: 94.197.122.85
Posted on Sunday, 21 September, 2014 - 05:22 am:   Edit PostDelete PostView Post/Check IP

I am suggesting not an off the self general purpose air bag but a properly matched bag.
Who made the originals?

(Message approved by david_gore)