OME BP-51 - 4Runner

onepremiere

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First let’s get a few things out of the way.

I am a terrible decision maker when it comes to parts for my vehicle

I am a 5th-6th Time is the Charm.

I am putting my foot in my mouth.

Ok so now that we’ve got that handled. Let’s talk about the 4Runner and the BP-51.



First Impressions



Huge. I know, thank you. These things are no joke. I seriously wondered if the front coil overs where going to fit in the bucket, because they are massive looking. The same applies to the rear, the shocks remind me of something you’d find on the back of a Class 1 car. In my head I was thinking, these are way too for this little baby 4Runner, it’s going to ride like a dump truck. – More on this later. The anodizing is very nice, all of the components look tough and durable. All of the hardware is black.



So if you’re familiar with my build thread you’ll know I have been through the 4Runner Suspension a few times. More than a few times. Enough times that I can change shocks, and coil springs on the front end in 1.5 hrs. using a floor jack and hand tools. (Patting myself on the back). This time around took me all day. Literally all day. Here’s why.



Prep



The BP-51 comes from the factory set to 20mm of preload.

I knew right away this was going to be too much lift for me. So I planned on taking 10mm of preload out. This required my trusty/sketchy Harbor-Freight Spring Compressor. I proceeded to attempt to compress the spring for about an hour. There is very little clearance between the body of the shock and coil spring. I chewed up the body of the shock pretty good and didn’t get very far. I was pretty upset. Before I did any more damage, I went to the Auto Parts store to get a different compressor. The spring compressor I got was a no go, same scenario. So I decided to take the “hooks” on the spring compressor and grind them down on a bench grinder for more clearance. This worked. I was able to compress the spring enough to adjust the collar without the hooks digging into the shock body.



Notes:

Use a lot of oil when making collar/ride height adjustments. On the threads, and especially between the spring and collar.



DO NOT back the pinch screw all the way out. If there is any tension on the collar while making the adjustments with a spanner wrench, the collar will skip/jump threads on the body of the shock. Loosen the bolt enough to allow the collar to spin.



Make sure your pinch bolt is positioned “out” so it is accessible once the coil over is mounted on the vehicle for future adjustments. Although from my experience, it is best to remove the shock.



Rebound and Compression Adjustments

I decided this was a good time to make changes to the rebound and compression while it was easily accessible. I adjusted all 4 shocks with 0

Comp / 4 Rebound.



For the Front OME Recommends

0-4 Compression (For Unloaded Vehicles)

4-8 Rebound (For Unloaded Vehicles)



Note: I made these adjustments off the vehicle, using a vice with soft jaws to hold the shock. Using the supplied spanner wrench it does take a little bit of force to turn the adjusting barrels. If you’re making adjustments while the shocks are installed, coil overs will be easy, rear shocks will be a little more difficult because they will want to spin. Tip: Use a leather belt wrapped around the body of the shock to hold the shock in place while you make the adjustments.



Install



Now all (4) Shocks were adjusted and ready to be installed. I tore down the front end and began installing.



Specific to the 4Runner, the Front “Fitting” Kit varies Left to Right. So it is important to follow the instructions. The same applies to the rear fitting kit.

Mounting the front coil over is straight forward. Mounting the reservoir takes some penitence. Unlike other manufactures, OME is using a really nice machined collar to mount the reservoir. The base of the collar has a t-slot that slides over the head of a 6mm bolt. Takes some finesse to get situated, and secured. The mounting position of the front coil over reservoir is outside the splash guard on the driver side and inside the splash guard on the passenger side.



On the right side, after install I noticed a bolt on the outside of the AC compressor was making contact with the reservoir when the engine was running. There wasn’t much I could to fix this (moving the reservoir forward or backward would not have made a difference). So I flipped the bracket, using one existing hole and drilling an additional 6mm hole I was able to make the reservoir mount outside the splash guard, similar to the driver side. There is less room inside the fender on the right side vs. the left side on the 4Runner. The right side houses a portion of the window washer tank. I addressed this issue with OME.



Note: OME emphasizes the proper position of the reservoir to avoid contact with the hose. So keep that in mind when mounting.

Mounting the rear shocks was pretty straight forward. The reservoir brackets mount under frame using existing 8mm bolt holes.

Again, the brackets are specific right to left.

Once the reservoir is mounted, check the clearance on your hose.



The Ride



Most peoples first and only question.

Adding large, heavier, stiffer tires to any vehicle is going to significantly reduce the on road comfort. Adding a suspension system capable of handling those larger wheels and tires is the key. I think I’ve found that with the BP-51.



Settings: See attached



I started with the settings attached. This gave me a very plush ride. The suspension absorbed everything. The rear carried on a bit after larger bumps so I knew right away I was going to need more rebound. After I made the adjustment, it was pretty amazing to be able to feel just (1) incremental adjustment. The rear was much more controlled now. I will likely increase by rebound in the rear by (1) more, putting the rear rebound adjustments at (6) and increase the front rebound by (1) putting the rebound adjustments at (5)



The 4Runner feels very controlled and planted now. It handles all road imperfections with ease. Doesn’t toss you all over the road or the cab. The 4Runner feels flat in the corners, I am much more confident carrying a little more speed around corners knowing I am not going to get thrown around. Basically, I can’t hear anything rattling inside the cab any more (The sound of plastic interior panels shaking/rattling over rough terrain).



All of these observations were made on the road, I have not taken it in the dirt-yet.



The biggest improvement is the compression dampening. You can feel the shock working. You can feel the suspension compress. You can feel it absorb the road bumps.



While driving a rough freeway, I tilted my mirror down to watch the rear tires, I was amazed at how much the suspension was moving, and how almost none of the movement was being transferred into the body. Basically the suspension was doing its job.



Conclusion



Yes, these are expensive shocks. But the moment you open the box, you will understand why. Once you mount them on your rig, all of your buyer’s remorse will vanish as you sail across the land in your new cloud.



I am seriously impressed, I thought I was impressed prior, but those impressions changed. There are a ton of great suspension products out there for the 4Runner, a lot of them I’ve tried and ultimately changed for something different. That’s not to say the parts I swapped out were no good, they just didn’t check my boxes. I am constantly telling myself, it could be better, and my OCD tendencies take control.



I didn’t receive these shocks for free or discounted in exchange for this review. This is my unbiased opinion.



More photos and some GoPro footage of the suspension working, coming soon.



I will be adding to this post as more comes to mind, and as I find all of my writing mistakes.



Feel free to ask questions, I am sure there is info I missed.



Cheers,



Jeff
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Awesome review Jeff, I've been looking at theses myself and hunting for a review just like yours - I've already started to feel the limitation on my Pros Bilsteins (fellow OCD'er). Even though they get the job done they don't seem to go above and beyond their first impressions I guess form the lack of adjustment.

I'd be interested to see how much better they perform off road..

Any pics of the rears mounted without the wheels?
 
i was trying to compress my bp51s.. with multiple compressors.. all those hydraulic ones.. failed on me. eventually never installed the bp-51, installed something else instead.

got swayed by a review that the bp51s are 2" and not 2.5"

scratched up one of my coilovers compressing like you hah. Will list mine for sale.. at a excellent price once i find some time.
 
If only their internal components actually matched their massive outside. They have huge housing for such a tiny piston inside doing the actual work.
 
"Mounting the rear shocks was pretty straight forward. The reservoir brackets mount under frame using existing 8mm bolt holes.

Again, the brackets are specific right to left.

Once the reservoir is mounted, check the clearance on your hose."



Hi,

What are you checking for exactly when checking the clearance on your rear reservoir hose? I'm assuming that there are no pinching issues during suspension flex? But just double checking this..

Thanks :hatsoff:
 
"Mounting the rear shocks was pretty straight forward. The reservoir brackets mount under frame using existing 8mm bolt holes.

Again, the brackets are specific right to left.

Once the reservoir is mounted, check the clearance on your hose."



Hi,

What are you checking for exactly when checking the clearance on your rear reservoir hose? I'm assuming that there are no pinching issues during suspension flex? But just double checking this..

Thanks :hatsoff:

Correct, just company QC...no issues as the braided lines are well designed
 

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I'm assuming since these shocks have remote reservoirs they are intended for high speed desert runs for hours at a time like the Kings. Right?
 
So what's the point? I get the whole $2500 King thing if you're doing desert runs, but what do these do that regular old Plain Jane OME shocks don't do?

I feel like I'm always posting this same thing in the suspension threads but I still haven't really seen a good explanation of why all of a sudden remote resi racing shocks are the must-have thing for traditional slow off roading with a daily driver truck.

I'm starting to think that guys are spending the big money on these setups because they're on highway 99% of the time and the racing shocks can be tuned to ride nicely on asphalt.
 
So what's the point? I get the whole $2500 King thing if you're doing desert runs, but what do these do that regular old Plain Jane OME shocks don't do?

I feel like I'm always posting this same thing in the suspension threads but I still haven't really seen a good explanation of why all of a sudden remote resi racing shocks are the must-have thing for traditional slow off roading with a daily driver truck.

I'm starting to think that guys are spending the big money on these setups because they're on highway 99% of the time and the racing shocks can be tuned to ride nicely on asphalt.

The point is internal bypass. The comments on piston size ignore or don't understand how bypass shocks work. There's more than one valve set and theoil doesn'tall flow through the piston. So the piston size comparison isn't a direct comparison. They have a lot more valved area than a 2.5 shock. And they have location specific dampening. Fox internal bypass are the same way. They should out perform the normal 2.5 shocks for a mixed use vehicle. I'd gladly trade my fox 2.5 for some internal bypass shocks.
 
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The point is internal bypass. The comments on piston size ignore or don't understand how bypass shocks work. There's more than one valve set and theoil doesn'tall flow through the piston. So the piston size comparison isn't a direct comparison. They have a lot more valved area than a 2.5 shock. And they have location specific dampening. Fox internal bypass are the same way. They should out perform the normal 2.5 shocks for a mixed use vehicle. I'd gladly trade my fox 2.5 for some internal bypass shocks.

Not a direct comparison for sure. but the BP-51 is aluminum... and thicker aluminum is needed to have comparable strength to steel. That in itself takes away from dampening?
 
So….what’s does the brain trust think about this guy’s comments about the piston size?

Starts around 12.20

https://www.youtube.com/watch?v=-MsKf1lIYI0

If your business model is based on customizing shocks and someone comes out with a system that doesn't need your service, you're probably not going to be very excited about it...

What needs to be recognized is that most of the oil doesn't flow through the piston except at the very ends of the shock. So using piston size as a reference for dampenign ability is simply mistaken understanding of the fluid dynamics going on internally.

For a simplified explanation, shocks use oil flowing through passage ways to convert kinetic energy into thermal energy. By constricting the passage way you can control the resistance to flow of oil and thereby control the amount of dampening you're doing. Regardless of shock size, the same amount of energy turns to the same amount of heat. Larger shocks do not generate less thermal energy. They absorb more energy per degree of temperature increase due to having more oil. Having a larger radiator in your car doesn't make the engine more powerful. But it may allow you to run it harder longer because you can keep it cool.

The larger piston as compared to a smaller one allows for more control of the fluid flow. Think about it this way - if you have two pipes - one has a 2" valve and one has a 1" valve, the 2" valve can offer more range of flow than the 1" valve. When wide open, to get the same flow volume through both you need more pressure on the 1" valve and you start to struggle to control flow accurately. The same happens in the pistons. larger pistons have more range of control and it's easier to get them to work better both on the slow and on the fast end of the spectrum. That's a big benefit.

BUT - the kicker here is when you start to use other valves that aren't in the piston to control the oil flow. That's what internal bypass shocks do. So instead of flowing oil through the face of the piston - they have bypass circuits that have their own set of valves. So instead of a 1" valve compared to a 2" valve where you can only adjust each one open or closed as a single valve, in a bypass you have 3 or 4 different 1" valves that are used in combination depending on where the shock is in its travel range. And you can then do a lot more with the dampening than you can with the single 2" valve. Looking only at the valve in the piston is missing the big picture of what's going on internally.

The ultimate point is that the smaller piston isn't necessarily a problem. Between a larger and smaller one - yeah, the larger one is pretty much always preferable. But between the small one AND half a dozen other valves in the other fluid paths, the combined performance can be really good and do a lot of things a simple single piston can't do. Like have nice soft small bump compliance while also ramping up dampening near the end of the stroke. You can't physically package a bypass and a large piston in the same size housing as a simple single piston shock.

Finally, thermal transfer is a function of the surface area of the shock body and the temperature of the outside air. If the shock body is the same size on the outside and the thermal transfer between the oil and the outer body is similar (comparing aluminum to aluminum shocks) then the heat dissipation will be the same. The argument that they overheat based on having a smaller internal piston diameter is simply wrong. Physics simply doesn't support that claim. Now if the OME has a smaller body or shorter canister length where heat is dissipated or something like that - sure it might be the case. But it has nothing to do with the internal piston size.

Hope that helps explain it. There are a lot of different versions of internal bypass shocks. The simple version is how King does it with only two stages and a full size piston. The complex version is how OME and Fox shocks like the TRD Pro do it with complete bypass circuits internally. The best version is how everyone does external bypasses that are independently adjustable - but those don't fit inside coil springs... so they require a setup with dual shocks.

In 5 years everyone will be selling internal bypass shocks and the simple single pistons like I have will be the budget model.
 
Here's a good explanation from FOX
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Update 8/28/18

So these puppies have been on my rig for a few months now and I've gotta say, I am still just as happy as I was on day one. Since I've installed these I've added around 250-300lbs (Rear Bumper and Spare) to the rear of the 4Runner. After adding the weight, the 4Runner was carrying on after big bumps/g-outs. That was fixed with a simple adjustment to the rebound collar. Brilliant. No changing shocks, no headache. Took 5 minutes to adjust both shocks to accommodate the extra weight.

You can feel each incremental adjustment in these shocks.

The 4Runner feels balanced front to back and side to side.

Yes they are expensive, but if you're like me and lose sleep over nonsense like how well your 4Runner handles speed bumps at the mall, then this like a lifetime Xanax.

Setting's today:

Front:
- 8mm Preload
- Rebound 3
- Compression 0

Rear
- OME 2895 Spring
- Rebound 5
- Compression 0

A note on springs compressors. I found god's gift to coilover spring compressors. I was able to compress the spring on the truck to make a collar adjustment. Yes, you read that correctly. ON THE TRUCK.

https://www.amazon.com/gp/product/B01M0UT55Y/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

Note: If you purchase one, get yourself a tube of high-pressure lube. Used in machining, drilling and tapping scenarios. Coat every threaded surface. It's a mess, but will prolong the life of the tool.
 

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