Anyone running 100 series springs and shocks on a AHC system with armor? (1 Viewer)

[thetoyotaman]

Anyone running 100 series springs and shocks on an AHC system with armor? Looking for posts of:
1. what armor you are running
2. what kind of lift you ended up with and how you got there
3. most importantly what kind of pressures your getting with the setup.

Also interested if the rear springs are 80 series.

Thanks!

 

[Wilsil]

Sorry, only running LC100 rear springs with AHC.
What do you mean by armor?

 

[thetoyotaman]

Bumpers, sliders, and anything that adds overall weight to the vehicle.

 

[thetoyotaman]

Ok it's late and I just realized I said springs and shocks. Well, obviously the shocks don't apply here. Either rear coils or coils and torsion bars.

 

[Wilsil]

OK.
Yep, standard non-AHC LC100 coils in the rear with dual spare wheel carrier with 2x AT tyres, fridge in the back, bulbar, sliders, transmission protection plate.

 

[thetoyotaman]

Thanks! Do you know what kind of pressures your AHC is running?

 

[Wilsil]

Better than before. I think I posted it in my topic.
He car is now even more bouncier, like "American style".

 

[BEG]

Anyone running 100 series springs and shocks on an AHC system with armor? Looking for posts of:
1. what armor you are running
2. what kind of lift you ended up with and how you got there
3. most importantly what kind of pressures your getting with the setup.

Also interested if the rear springs are 80 series.

Thanks!

This is one of those not-what-you-asked responses, but I hope it helps shed some light on what I think you're getting at.
The AHC spring rate is a combination of the straight, mechanical spring rate and the progressive gas spring rate of the compressed nitrogen in the globes. Assuming everything is in working order, you really only need to keep the system within the right pressure range for it to function properly.

That being said, in the case of the rear suspension, every additional 200lbs over the rear axle will increase the pressure by 1MPa with stock AHC springs (90lb/in rate). As an example, the King KTRS-79 springs (130lb/in rate) will lower the pressure by 3MPa. That's the equivalent of an additional 600lbs over the rear axle. The 80 series and 100LC springs are 150lb/in and 170lb/in respectively. I'll let you do the math on how much additional weight you would need to be carrying to get the system back into spec. Add to that the fact that new OEM globes will have a higher pressure gas charge than old ones, and aftermarket Citroen globes will have a higher pressure gas charge than new OEM and you can see that it's easy to end up with an oversprung suspension pretty easily if you go down that path.

For the front, you run into additional challenges because the gas spring and torsion bars work in series (instead of parallel, like the rear) and there's no available happy-medium between the AHC 25mm bars and the LC 28mm. However, the adjustable pre-load of the stock AHC bars and the variable damping range of the AHC system allows proper damping even if the front is slightly undersprung. It'd be ideal if someone made a 26.5mm t-bar, though.

To bring all that into perspective, I run steel skids, sliders, steel front bumper, winch, roof rack and a family of five with all the associated crap that comes with us and I run stock t-bars (cranked and re-indexed) and King rear springs. My pressures are 6.7 (F) and 5.6 (R).

 

[thetoyotaman]

Thanks!

 

[neilsen100]

I am running used 80 series springs on the rear to help bring pressures back into line. At last measurement the rears were 5.2 Mpa-g. I figured the 80 series springs were a little much in terms of spring rate but given they came off a truck with over 120k, they must be a little weaker. Overall very happy that I did this because the system works better now and will go into H mode again.

Things on the truck full time are: Dissent rear bumper with two swing outs, shelving system, full camping kitchen gear, Fridge, Tepui ruggedized RTT on Rhino Rack Platform.

On the front I do have a Dissent steel bumper. My pressures are reading high at 8.4 Mpa-g with stock torsion bars (200k on them) and without having adjusted them. I suspect that once I find the time to adjust the stock bars things will be just fine.

Hope this helps.

 

[thetoyotaman]

Thanks! This is exactly the kind of data I’m looking for.

 

[PabloCruise]

This is one of those not-what-you-asked responses, but I hope it helps shed some light on what I think you're getting at.
The AHC spring rate is a combination of the straight, mechanical spring rate and the progressive gas spring rate of the compressed nitrogen in the globes. Assuming everything is in working order, you really only need to keep the system within the right pressure range for it to function properly.

That being said, in the case of the rear suspension, every additional 200lbs over the rear axle will increase the pressure by 1MPa with stock AHC springs (90lb/in rate). As an example, the King KTRS-79 springs (130lb/in rate) will lower the pressure by 3MPa. That's the equivalent of an additional 600lbs over the rear axle. The 80 series and 100LC springs are 150lb/in and 170lb/in respectively. I'll let you do the math on how much additional weight you would need to be carrying to get the system back into spec. Add to that the fact that new OEM globes will have a higher pressure gas charge than old ones, and aftermarket Citroen globes will have a higher pressure gas charge than new OEM and you can see that it's easy to end up with an oversprung suspension pretty easily if you go down that path.

For the front, you run into additional challenges because the gas spring and torsion bars work in series (instead of parallel, like the rear) and there's no available happy-medium between the AHC 25mm bars and the LC 28mm. However, the adjustable pre-load of the stock AHC bars and the variable damping range of the AHC system allows proper damping even if the front is slightly undersprung. It'd be ideal if someone made a 26.5mm t-bar, though.

To bring all that into perspective, I run steel skids, sliders, steel front bumper, winch, roof rack and a family of five with all the associated crap that comes with us and I run stock t-bars (cranked and re-indexed) and King rear springs. My pressures are 6.7 (F) and 5.6 (R).

Nice post!

I thought I had heard that 80 and 100 rear springs had the same rating? But it was LX 450 springs that were a little softer than the 80/100 rear coils?

We have BIO rear bumper and sliders, and run an Iron Man 80 qt fridge in the back of ours. W/ King rear coils and adjustment to the front torsion bars and a few fluid changes we are running 6.5 F/5.5 R (those were w/o fridge in the rear).

 

[PabloCruise]

Nice post!

I thought I had heard that 80 and 100 rear springs had the same rating? But it was LX 450 springs that were a little softer than the 80/100 rear coils?

We have BIO rear bumper and sliders, and run an Iron Man 80 qt fridge in the back of ours. W/ King rear coils and adjustment to the front torsion bars and a few fluid changes we are running 6.5 F/5.5 R (those were w/o fridge in the rear).

Also running 33's (235 75R16?), so a little extra weight of the spare in the rear.

 

[BEG]

Nice post!

I thought I had heard that 80 and 100 rear springs had the same rating? But it was LX 450 springs that were a little softer than the 80/100 rear coils?

We have BIO rear bumper and sliders, and run an Iron Man 80 qt fridge in the back of ours. W/ King rear coils and adjustment to the front torsion bars and a few fluid changes we are running 6.5 F/5.5 R (those were w/o fridge in the rear).

Thank you. I owe it all to the AHC gurus on this forum who have taken the time to educate me.

You might be right about the LX450 vs. 80LC springs. The spring rate I posted was specifically for the LX springs. I assumed they were consistent across the 80 series.

 

[thetoyotaman]

I read the 96-97 80 and 450 are the same.

Does adjusting the front torsion bars to get it in spec after a winch and bumper affect the rear axle at all?

 

[codertimt]

Thought I'd check in...also running used 80 Series in the rear. 4x4 labs rear bumper with spare tire and jerry cans. Dissent Front with full bar and winch. OPOR sliders. Fridge, small homemade drawer, sub and amp...

The 80 springs actually put my pressures on the low side...the only documentation I can find is that I said about 5% on the low side. I was remembering 4.8, and I know I actually lowered the rear a titch to put more weight on the springs, so I'm guessing with the 5% comment it was probably around 5%. I put the front also on the lower side of pressures to keep things consistent front to back(still stock AHC bars) and have had no real issues. Need to check and adjust again, just haven't taken the time to.

Does adjusting the front torsion bars to get it in spec after a winch and bumper affect the rear axle at all?

From what I remember when adjusting, bringing the front into spec put a little more pressure on the rear...not much couple of tenths...

 

[PabloCruise]

From here: Updating AHC system

470 AHC spring rate = 95 lbs/in
King = 130
450 = 150
100 = 170

Kurt @cruiseroutfit advised me the 80 & 100 rear coils are the same rate.

 

[thetoyotaman]

I wonder what an ideal spring rate would be then? Maybe 110?

 

[thetoyotaman]

I have some 80 series springs I’m considering trying with the addition of a rear ARB bumper and tire carrier since I already have both. Any thoughts on if this will change the ride height?

 

[codertimt]

I have some 80 series springs I’m considering trying with the addition of a rear ARB bumper and tire carrier since I already have both. Any thoughts on if this will change the ride height?

Uh, it's AHC, so no. Unless things are so out of wack it can't manage to adjust the height to the correct level(which is what you might be getting at), the AHC is going to put the height at a certain level and as we've been discussing, what changes is the hydraulic pressure once we get there. Now my Low isn't quite as low as it once was, but Normal levels haven't changed. And low goes down enough that the sensors are happy and register L. Don't know exact weight, but from what I've seen the ARB isn't as robust as something like my 4x4 labs bumper, so i't probably isn't as heavy. But it should be enough weight, especially with tire hanging off the back, that the height will be normal and neutral pressures will simply be on the low side. Otherwise unloaded, it might be a little harsher riding that you are used to, but shouldn't be too bad. And loaded for a trip should be pretty close to perfect...or at least close to factory spec...