Floating RTAB limiters

[TH3 Shifty]

For you guys with floating RTAB limiters(basically all limiters that are NOT Turnermotorsports) do yours rattle?

Do you have metal ones like FCPeuro?

or composite like Vorshlag, Ground Control, ECStuning?


anyone have the NON-floating style of Turners?

i have heard that the metal ones, although tight in the RTAB pocket, do rattle. Im replacing my annoying UUC RTABs that squeek and drive me insane.

FCPeuro's RTABS are metal but cost the least $22
Turnermotorsports(non floating) cost the most $89
ESCtuning (derilin) cost $49
Ground Control are "self-lubricating plastic" - $60
Vorshlag, does not state compound used - $55

[Carpy2]

I was looking at RTABs and limiters and decided to go with FCPeuro's RTAB/limiter kit. My thought process was that since it's just a piece of metal (and only $22 compared to Turner's $90 option, yikes) I can always just drill two holes through it and voila! You have Turner's $90 limiter option. I was also playing with the idea of some sort of plastic or poly coating on the backsides that contact the RTAB frame, just to reduce any nvh that they may cause (but this could create squeaking). The coating would be ultra-thin because, as you said, it's a tight squeeze already. I personally can't find people complaining that the metal ones rattle. I understand the squeaking from friction against the frame, but there's literally no room for the limiter to move side to side to create a rattle, afaik.

If you still haven't made up your mind in about 1-1/2 weeks, I'll let you know how the metal FCPeuro limiters work out for me.

[pbonsalb]

I used the vorshlag. It may be that any Delrin is similar. I would skip poly - there are some poly limiters so beware. Metal — I don’t know but would be concerned it could make metal on metal noise. Might not show up for a while so the initial report right after installation offered above may not hold up long term. I am sure there are people who have had metal
Limiters for years who can report on long term street use.

[TostitoBandito]

Vorshlag's use this family of materials in their limiters:

https://en.wikipedia.org/wiki/Ultra-...t_polyethylene

It's the type of stuff used in composite body armor, climbing and skydiving cords, and in artificial joints. Seems like a pretty logical material to use for something like this, and seems to be slightly better than nylon or delrin in terms of the properties you'd care about for a bushing limiter.

[scooper]

I have had no issues with akg nor vorshlag delrin ones.

[tjm3]

Just buy a chunk of 3"dia Delrin and make your own. Delrin or nylon works. The HPDE mentioned above is the same stuff of cutting boards. You can get a whole 1/4" board for a few bucks almost anywhere, including kmart, much more costly at Williams-Sonoma.

Black and white Delrin.
delrin.jpg

[Gene V]

I've had the GC limiters for some time now...no rattle or squeak.

[NoLastName]

Delrin works perfect in this application and makes no noise. There are rubber bumper tabs on the RTABs themselves that actively sandwich the limiter shims between RTAB and bracket. I had a set of Ground Controls for several years. It's not needed to retain the limiters in any way.

[Braymond141]

Just buy a chunk of 3"dia Delrin and make your own. Delrin or nylon works. The HPDE mentioned above is the same stuff of cutting boards. You can get a whole 1/4" board for a few bucks almost anywhere, including kmart, much more costly at Williams-Sonoma.

Black and white Delrin.
delrin.jpg

Not exactly a DIY process without a lathe. We’re not talking expensive parts either.

[modernbeat]

The Vorshlag RTABs are Polyethylene. That material choice was not an accident. We've tried Delrin and other "hard" plastics. They sure machine a lot easier, but they are too stiff IF the arm gets to the end of the movement, putting too much twisting force into the tub. The Polyethylene will cut if you end up overextending the suspension, saving the sheetmetal. But it's broad face still prevents the bushing from overextending.

On EDIT: I thought we had the material listed, and why we use it over Polyurethane or Delrin in the listing for the parts, and sure enough, we do. It's no secret, and we do disclose what it is right in the listing despite what the original poster thought.
https://vorshlag-store.com/collectio...iters-full-set

[NoLastName]

The Vorshlag RTABs are Polyethylene.

Ah, good correction. It's easy to confuse polyethylene and delrin as I did above. The GC limiters may be polyethylene as well... not sure.

[TostitoBandito]

The Vorshlag RTABs are Polyethylene. That material choice was not an accident. We've tried Delrin and other "hard" plastics. They sure machine a lot easier, but they are too stiff IF the arm gets to the end of the movement, putting too much twisting force into the tub. The Polyethylene will cut if you end up overextending the suspension, saving the sheetmetal. But it's broad face still prevents the bushing from overextending.

On EDIT: I thought we had the material listed, and why we use it over Polyurethane or Delrin in the listing for the parts, and sure enough, we do. It's no secret, and we do disclose what it is right in the listing despite what the original poster thought.
https://vorshlag-store.com/collectio...iters-full-set

Thanks for the additional explanation. I'll be ordering some for my winter project soon. Oh, and your motor and transmission mounts are a thing of beauty. It's too bad nobody will be able to see them once I put them on.

[modernbeat]

I wish there was a better material other than Polyethylene, because it's a huge hassle to machine. Like, worse than just about anything else we work with. Even worse than stressproof steel.

[cashmancab]

^^^^ Are you using UHMW or HDPE? UHMW will machine a little better and may still provide the relief you're looking for.
ABS might be worth looking at. Is inexpensive and machines better than PE.
Are you using Delrin or Copolymer Acetal? The copolymer wont be quite as hard as the Delrin. Doubt you would see much relief in this application but it might be enough.
Another option is Delrin AF (13% Teflon Delrin). The Teflon will soften the Delrin polymer, lubricate the wear surface (eliminate noise), but be much more expensive.

on a side note, have you tried Delrin AF for suspension bushings? I would think it would provide majority of the properties of Delrin but would reduce the Noise and squeaks people complain about. Not sure why no one offers this.

PS - The Company I work for produces all of these. PM me if you have questions or comments. Good chance you are machining our material already.

[dlhjimmy]

I have ECS limiters. They've been silent since they were installed about a year ago ~7k miles.

[propcar]

so have enough people been able to test the spherical sealed type RTAB's like Bimmerworld/Synchro design works? Given they're extremely much more money than an OEM RTAB + Limiters... I think I'll be going with one of these when the time comes to do my RTAB's again.

http://www.bimmerworld.com/Suspensio...aring-Kit.html

https://www.fcpeuro.com/products/bmw...4aAh2vEALw_wcB

[Carpy2]

Update: After revisiting this thread I was able to change my order before it shipped out. Stuck with Lemforder RTABs, but was sold on the Vorshlag limiters.... ^^

[TostitoBandito]

I also just ordered the Vorshlag limiters to go along with the rest of my bushing party in the next month or two.

[mitch500]

I'm on lemforder rtabs and FCP limiters

[NoLastName]

so have enough people been able to test the spherical sealed type RTAB's like Bimmerworld/Synchro design works? Given they're extremely much more money than an OEM RTAB + Limiters... I think I'll be going with one of these when the time comes to do my RTAB's again.

I've been using Ground Control spherical RTABs for a couple years. They're an unsealed spherical design. Awesome on track but I wouldn't want to use them on the street in all weather conditions because dirt and water can get in. They're race parts that must be inspected periodically.

Personally I would not hesitate to use Bimmerworld sealed sphericals in a street car. When the GCs wear out I'll switch to BW. Using an OEM ball joint seems like the best solution for completely free articulation, but with zero unwanted lateral movement and (potentially) OEM-like service life. The seals keep grease in and contaminants out. As far as NVH goes, I didn't notice an objectionable increase from the GC spherical RTABS. I imagine the other designs that use sealed ball joints will be similar if not better because they're packed with grease.