jdizzle37

iTrader: (8)

I'm surprised these haven't been mentioned here on EvoM (at least after searching a bit) but I think this a pretty interesting product that I wanted to share with the community. Makes sense in theory and there is a nice detailed article of this being installed on a Nissan Skyline R34 GT-R that you can read here at Speed Hunters.

Here's a video explaining the rigid collar and how it works. Luckily, they make these for the front and rear sub frames on the Evo V through X's.

http://www.youtube.com/watch?v=L_h-2...layer_embedded

griceiv

iTrader: (2)

There's a good reason they haven't been mentioned.

Dallas J

iTrader: (1)

That video sure makes a lot of nonsense claims...

03whitegsr

iTrader: (8)

I thought somebody already posted these?

FWIW, the majority of a joint stiffness comes from the friction between the pieces being bolted together caused by the load of the fastener. I'd have to double check, but I don't remember seeing any fretting wear on my mounting points. If you aren't getting wear, you aren't getting movement.

The idea of a take up collar isn't a bad idea and is probably used in some applications. However, I don't think it will have a significant impact on any car and in particular, on the EVO as chassis uses bolt inserts that could still move around if their claims were true. I don't think their claims are true anyway though.

The only actual benefit I could see is that it might make it so you could remove the subframes and not need to realign the car after reassembly. You can actually get about 1/16" of movement in any direction from the center point on the front and rear subframes because of the clearance in the bolt holes.

MinusPrevious

iTrader: (3)

Im not ready to dismiss it.

I read the OP's attachment which shows the findings & install on a Skyline. Im interested to a degree.

Heres what they found when the subframe nuts were removed (movement and off- centeredness)

n2oiroc

iTrader: (33)

i dont see any movement, i see where the nut rubbed paint off and thats it.

griceiv

iTrader: (2)

I've loosened the front sub frame while it was on an alignment rack and intentionally moved it around to see how much variance there was. Max change in camber was less than .1deg. There are no rubber bushings in the evo subframe and when the subframe bolts are torqued to spec (~115 ftlb) the subframe does not move, ever.

I've never had to realigned the car after removing the subframe.

jdizzle37

iTrader: (8)

I don't think this product is intended to address dynamic alignment changes as much as decreasing movement in a crucial area so the suspension can operate with less resistance from stored energy in the chassis.

They admit it is not nearly as effective as welding but this is still an improvement that is just another option for people. Nonetheless, the individuals who have ACTUALLY USED these have had positive feedback and have reported improvement in the areas where the product claims.

griceiv

iTrader: (2)

...say what?

the spring and shock stiffness are several orders of magnitude lower than the stiffness of the subframe bolt connections on the evo. There is no stored spring energy in the chassis on an evo. All those bushings do is align the holes in the subframe and body to a common centerline during assembly. At no point is there any movement of the subframe once it's torqued down, with or with out alignment bushings.

Solenoid

jdizzle37 Dont get me wrong, but your comment was way above my simple brain. I liked it enough to add it to my Sig

Good thread topic for sure. Been following it from the beginning. There still maybe something to be gained from these sleeves.

griceiv. You seem to have the subframe experience.
As noted, maybe the simple clamp force is enough to keep both mating surfaces from movement when torqued properly
Mike

Construct

iTrader: (4)

But we already established that subframe movement isn't a problem.

The placebo effect is very strong. Especially when you spend money on something, spend a few hours installing it, and then start looking for results.

This is a waste of time and money.

Solenoid

Hey, this is just a group of gear heads talking here on the internets. Nothing has been technically proven

I do like your comment about the placebo effect. Add a part & justify its effectiveness

jdizzle37

iTrader: (8)

Sorry, I think I used poor word choices in my response. What I'm referring to when I say "stored energy in the chassis" is the body flex or torsional flexing that happens in body-on-frame cars as this is considered sprung mass. I've frequently heard the chassis of a car talked about as a kind of the "fifth spring" because whenever "flexing" happens, it affects the handling of a car and makes it kind of unpredictable in terms of controlling it; especially because the flexing isn't linear (sometimes a small load will make the chassis flex and sometimes a large load won't flex it all). Hence, things like strut bars and chassis braces are used to minimize this flexing and make the handling more predictable and consistent.

In the case of the rigid collars, my understanding of it was they are there to provide a more solid connection to the sub frame reducing the chassis flexing at that point of the car and allowing the unsprung components (dampeners and springs) to remain planted to the ground. I didn't take from this understanding that the sub frame itself was moving or flexing.

I hope I conveyed how I understood how this works a little more clearly. Perhaps other people can clarify or let me know if I'm totally off-base.

jdizzle37

iTrader: (8)

The placebo effects is certainly very true in many cases.

TommiM

iTrader: (19)

Im not sure if subframes have a natural 'play' to them or not. I have seen certain manufacturers use subframes that have notches on them to center onto the vehicle. If the subframe gets bent you can tell because it wont line up to the notches and wont mount correctly.