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Discussion Starter #1 (Edited)
After MUCH deliberation, I finally ordered the first parts for my lift. I decided to go with Bilstein 5100's all around and an adjustable lift shackle for the rear.

Reasons:
1. Shock Travel - the front Bilsteins have 4.71 inches shock travel, which isn't much less than the extended Radflo's 5 inch travel. It ends up being about 7.75" at the wheel for the Bilsteins, compared to 8.25" for the Radflo's (stock is 6.6").

* All travel numbers are based on a 1.65:1 ratio - which seems to vary depending on who I talk to :scratch:

Yes, I know there is damping differences with the shocks, but my truck is used as a DD and the type of wheeling is more crawling than anything else. I think the Bilsteins will do just fine.

2. Cost - The entire cost is about $500 and will allow for later upgrades, such as a higher spring rate in the front or a small spacer, AAL in the rear, UCA's, cam bolts, etc.

3. Lift Amount - I'm planning on going with 1.5" in the front and rear to begin with. Any higher on the Bilsteins and I'm afraid of topping out as others have found.

4. Spring Rates - Staying with stock spring rates because I don't have a winch bumper on and typically don't wheel with a ton of stuff loaded in the truck. I added one of those cheap Autozone helper springs to the rear about 2 months ago and have no complaints. It made the rear just stiff enough to do the job. The shackles will just give me more usable up travel.

Ordered everything through Nisstec. I will add that when I talked to Chris, he mentioned something I hadn't read, or thought about when lifting the front of our X's... Bushing deflection at full droop. I originally thought of installing a 1" spacer on top of the Bilsteins and thought, based on my measurements, that there would be enough clearance to keep the UCA's from hitting the CB. Chris said that the Bilsteins only allow about 1/4" clearance between the stock UCA's and the CB and some of that would be taken up when the bushings deflect. No matter what spacer is used, he expected CB contact. So.... I'll wait to add a spacer or stiffer coils until when I do UCA's.

I don't know if I'll do a build thread. Not an exciting or different project. Hopefully, it will happen this wknd.

:rockin:
 

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1. Shock Travel - the front Bilsteins have 4.71 inches shock travel, which isn't much less than the extended Radflo's 5 inch travel. It ends up being about 7.75" at the wheel for the Bilsteins, compared to 8.25" for the Radflo's (stock is 6.6").
Your bump stops limit up travel before your shocks do (by design) so the total travel available is a little less than the shock provides (unless you install spacers).


* All travel numbers are based on a 1.65:1 ratio - which seems to vary depending on who I talk to :scratch:
Actually it varies depending on the position of the control arms, or, more specifically the angle of the control arms.

At perfectly horizontal all the deflection at the wheel counts as travel, but as you get more extreme angles a component of the deflection is also inward. Although the ratio of shock to wheel defection stays the same, what we care about is shock deflection verses horizontal defection at the wheel. Since this varies slightly depending on the angle of the arms, its expected to get a variety of answers. 1.65:1 seems to be a good approximation.

I think I remember you saying you're a mechanical engineer, so maybe you actually care. Otherwise, please disregard my essentially pointless math ramblings.
 

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Discussion Starter #4 (Edited)
The X got its first major mod this wknd with a set of Bilstein 5100's and a shackle lift in the rear. I decided to set the front up with what Bilstein says is 1.5" of lift and put the Nisstec adjustable shackles on their middle setting, which is also supposed to be 1.5" lift

First, some notes about the adjustable Bilsteins. They have 5 grooves for the circlip that raises the spring perch. The circlip is fairly easy to move from groove to groove with some needle nose pliers. I took out a caliper and measured the distance between grooves. They are all 1/3" apart. After all the investigation I've done on the front suspension and figuring the ratio of wheel travel to shock travel is about 1.65:1 and assuming the bottom groove does indeed replicate the stock spring perch location, each groove on the Bilsteins would then lift the front not the 0.5" they claim, but actually 0.55". Not a lot of difference, but that means on the 4th notch up, the front should be lifted 1.65" instead of 1.5". Once the install was complete, I measured and re-measured... I ended up with 1.75" lift.

I can't say if it's the shock travel/wheel travel ratio being actually 1.75:1, or the Bilstein's groove positions being slightly higher than stock.

With all the how to threads on the front shocks, I didn't bother with pics. Suffice to say that the rented (free) spring compressor from O'Reilly was a PITA, but it worked. I'm not afraid to use one again.

For the rear, the shackles and extended 5100's were only part of what I decided to do. I had a set of helper springs behind the axle on each leaf and decided to move them in front of the axle. I see no reason they can't be installed in front. I also decided to remove the rear sway bar.



To my surprise, the rear sway bar is NOT a solid bar, but a thin wall tube - maybe 1.5mm wall thickness. It's very light, but more importantly, it's easy to flex. I honestly don't know why Nissan even bothered with the rear sway bar... BTW - the front is a solid bar. I know about tortional rigidity of tubes and bars and know the center of a bar is not responsible for the majority of its rigidity, but c'mon... a rather small diameter tube? Oh well, it's gone and I don't miss it.

Notes about droop and brake lines - With the extended 2 - 4" lift rear shocks (bought for future upgrades), the axle can drop a long way. The brake and ABS lines are all stretched to the max at full droop.





Lift from shackles - I measured a (surprisingly) 1.75" lift with the shackles in the middle lift position. These are some BEEFY shackles!



Total height to fenders. Between the lift and the 33" tires, the fenders now sit at 36.5" front and 37.7" rear. A moderate 1.2" rake, which is fine.

The ride - On road, the ride is very plush. Since this is a DD, I appreciate the smooth ride. I did notice the dreaded topping out clunk over speed bumps when taken at higher speeds. I decided to do a little off roading to see if I would notice it there... Not once. I hit hard enough to bottom both ends and on the back side of all bumps, there was not sign of any clunks. :laughing3:

A little complaint. The Bilsteins are under-damped IMHO. They're great on road, but off road, they could certainly use more damping. The truck feels pretty bouncy when driving at speed. BUT, at typical wheeling speeds, they're fine. I expect when going through really rough stuff in 1st gear/4 lo, they will be quite nice.

Rear sway bar - I really paid attention to the roll when cornering on the road and if there's any difference, I couldn't tell. Where I COULD tell there was a difference was off road. It's obvious with more total travel at both ends and no sway bar, the truck floats better over rough terrain. I could actually feel when the rear would flex, instead of jostle to the side like it did before.

Latest pics -





Quick articulation pics:







Now, to save up for some sliders and skids.... :rockin:
 

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Discussion Starter #5
Your bump stops limit up travel before your shocks do (by design) so the total travel available is a little less than the shock provides (unless you install spacers).

Actually it varies depending on the position of the control arms, or, more specifically the angle of the control arms.
I didn't bother to check wheel travel after the install and after bottoming it on a test drive, you're right about hitting the bump stops.

I agree with the angle of the lower control arm and how that would vary the ratio, but the total change in angle isn't that big. By my estimation, it's less than 30 degrees total. The ratio drops to about 1.5:1 at the limits of travel, which is good because it's harder for the wheel to compress the shock near the shock's limits of travel.
 

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Looks good man! I've been contemplating about upgrading from the OR Bils to the 5100 series.. Also - the front sway bar is hollow, it's just pinched on the ends.
 

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Discussion Starter #7 (Edited)
Looks good man! I've been contemplating about upgrading from the OR Bils to the 5100 series.. Also - the front sway bar is hollow, it's just pinched on the ends.
Really? I didn't remove the front sway bar, but when I was moving it around, it felt pretty heavy. I thought it was solid. Hmmm.

I can't compare the OR Bilsteins, but I'll ask a question. I'm sure your familiar with speed "humps" instead of bumps. With my stock suspension, it was pretty bad hitting those things at speed. Anything over about 20 mph had the X bottoming bad in the rear and bouncing quite a bit. This morning, I hit a couple that I go over a few times week, except this time I was doing about 40 mph. I was very surprised at how well my setup handled them. I'm sure I could hit them at higher speeds, but it's a residential street and I was being an idiot as it was. How does the OR suspension handle those things?

I am still impressed with the on-road ride quality. It's very smooth.

Now, a note about the rear shackles - when I installed them, I noticed the stock bushings were slightly worn and the spacer that fits into them with the new shackles slid right in without problem - actually I thought it was a bit too loose. I've noticed that the rear axle moves side to side more than before when turning. I looked through my side view mirror and watched the rear tire as I made some small S turns and I could see the tire moving back and forth maybe an inch or so. The only thing locating the axle laterally is the leaf springs, so I think with the added height of the shackles, it loads those rear bushings more and allows the axle to drift side to side more than before. It's not really a problem and doesn't horribly affect handling, but it's definitely noticeable. It makes the rear end feel a little sloppy. Oh well, c'est la vie.
 

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I can't compare the OR Bilsteins, but I'll ask a question. How does the OR suspension handle those things?
Same. Like poop. The major issue with the stock setup is not insufficient dampening, it's insufficient up travel. Also, the bump stops have a large metal core, they are really only coated in rubber. It's a terrible design and makes bottoming out very harsh.

The shackles and AAL did more to prevent bottoming out on those speed humps than the shocks did.
 

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Now, a note about the rear shackles - when I installed them, I noticed the stock bushings were slightly worn and the spacer that fits into them with the new shackles slid right in without problem - actually I thought it was a bit too loose. I've noticed that the rear axle moves side to side more than before when turning. The only thing locating the axle laterally is the leaf springs, so I think with the added height of the shackles, it loads those rear bushings more and allows the axle to drift side to side more than before. It's not really a problem and doesn't horribly affect handling, but it's definitely noticeable. It makes the rear end feel a little sloppy. Oh well, c'est la vie.
Relatively cheap replacement bushings:
http://www.nissteclifts.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=58987&category_id=157&option=com_virtuemart&Itemid=76

You could also try these:
http://www.mooreparts.com/8755-DSA-SBA2041/

They'll prevent the bushings from degrading and prevent any side to side motion but obviously the swing won't have any resistance, so there are downsides. Probably not worth the $$ unless you're pushing big travel numbers, like >10".
I want them.
 

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Yeah, I'm not sure what the dampening is on the Bils either - seems like most companies don't release information like this, but I have an AAL and a shackle so I don't usually bottom out on speed humps. I just need something a little longer than stock!
 

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Discussion Starter #11
Yeah, I'm not sure what the dampening is on the Bils either - seems like most companies don't release information like this, but I have an AAL and a shackle so I don't usually bottom out on speed humps. I just need something a little longer than stock!
For the money, the 5100's are great. Every single day I drive it, I notice that the rougher roads that use to rattle the truck don't seem so bad. I hate to say it, but it feels almost car-like on the road.

The more I drive it, the more I understand the compromise made in damping. Light damping is great for on-road use, heavier damping takes big hits without bottoming. Bilstein must have decided to bias towards softer damping. Considering I'll spend 90% of my time on the road, it makes sense. I'm not trying to build a desert race truck that can handle whoops at 50 mph.

As far the the up travel you mentioned, the way mine is set up, it is biased in the front for more up travel than down. With the shocks set on the 4th groove from the bottom, I figure I'm an inch higher than the mid-point of the shock travel, which gives me 4.71"/2 -1' = 1.35" shock down travel available, which is about 2.25" wheel travel. That doesn't seem like much, and since the front will top out on speed bumps occasionally, I know it's not "perfect", but the other option of dropping the strut mount 0.33", which lowers the front about 1/2" only gains me another 1/2" wheel down travel. Plus, I don't have topping out issues off-road, only speed bumps hit at certain speeds (faster or slower is better). The (wheel) up travel is about 5.5", so it has enough travel to take hits much better than before.

I can say that I've hit some curbs (intentionally) at speed and the added up travel absorbs the hit without bottoming. That's the kind of crap I run into off-road - an unexpected rock, ledge or bump that bottoms the truck. I'd rather have the additional up travel to take that hit.
 

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Discussion Starter #12
Just some pics putting the new suspension through its paces. Very happy with it!





 

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Nice pics! Looks good man.
 
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