I have been looking into buying a set of LCAs and a UCA for my new ride (2011 GT 500). The J&M products have caught my attention, they have what appears to be the same part for a 2005 - 2010 for around 60$ cheaper than if it is for a 2011. Is there any difference in the suspension from 2010-2011? Also they dont have a UCA for 2011 but have several different types for the previous years... If anyone has any experience in the area please let me know, i would like to get these parts but wouldnt mind to save a few buck if i can...

Thanks..

 

If you'd like to call me, I can help. A 2010 and older upper arm that does not have it's own bracket will not bolt in to a 2011. If you go with a setup that has an arm and it's own bracket (I have them from Steeda and UMI) then it will bolt right it.

Lower arms are the same....

I know you are looking to save a buck. But you do get what you pay for, and J&M's are nothing special--in fact their 3-piece urethane bushings still bind up (urethane on urethane doesn't slide very well). I'm a big fan of UMI parts and you can't go wrong with Steeda either. I carry both brands--Maximum Motorsports too.

 

What is the difference in the UMI or Steeda bushings??

 

UMI has poly bushings, so does Steeda (and about everyone else). They are all pretty much the same... Steeda has some arms that use a spherical bearing in the rear. They also have other versions. UMI has multiple version, and they make roto-joints as well.

There are a lot of choices, a lot. I'm happy to discuss the differences with you but I can't really make a recommendation without talking to you (if you don't know the differences already and it seems you could use some help there).

 

I have had experience with urethane bushings, and you mention that the steedas have spherical bearings in the rear. I was under the impression thats what the ball was in the rear of the J&M and CHE LCAs. Is there really a big difference in poly over urethane? If so i would be very interested to hear why... also i will check out the steeda LCAs.

 

Except their spherical joint is NOT urethane on urethane. It has a hard poly ball and soft cups that keep the ball centered in the steel arms. Sam if you're going to bad mouth someone's product at least get it right. Or are you just desperate for sale?

 

The polyball isn't entirely free from offering resistance of some sort. Whether there is much friction/stiction between the ball and the metal sleeve or friction/stiction between the ball and the cups (of unspecified material) probably doesn't matter in most street driving, since there is still stiffness coming from the cups having to deform in order to let the inner sleeves rotate relative to the outer shells.

The bottom line seems to be that while the polyballs give you better axle location than OE rubber without particularly adding any "roll bind", they don't particularly reduce the "bind" that's there with the OE rubber either (working from the Maximum Motorsports baseline test results, I get rubber at 5 lb/in for two LCAs to be about 12.5 ft-lbs @ 5° per LCA). They're still a better street compromise than plain poly, at least in this respect (poly numbers below). At a rough guess, polyballs probably "drive" similar to MM's 3-piece poly (which is another bushing design that falls midway between OE rubber and all-metal sphericals).

http://www.hotpart.com/shop/index.ph...ct_detail&p=45


Norm

 

Here we go... again. So hard poly and soft poly aren't both poly? Do you not have to lube urethane when running against something hard like, say steel (can you say swaybar bushings)? Of course you do. The ball and "cups" ride on each other, just like the chromed steel ball in a UMI roto-joint rides in the delrin "cups" or races. Delrin is self-lubricating plastic. Harder than urethane and slicker too. And the ball which is steel. A setup like the J&M does bind less than a normal poly bushing. But as it flexes the soft "cups" are forced to deform... and the entire time the ball and the cups have friction between them....

The idea is fine though nothing new. The execution is, IMO, not so hot. Is that bad-mouthing because I don't agree (and have the ***** to say so and explain why)? Or is it only because I also sell parts?

I always manage to make 98% of folks happen and **** of 2%. I can't please everyone all the time, and I won't change my opinions to suit what you want to believe. I'm sorry.

 

I don't know about the CHE's. But J&M either uses a rod-end or their poly-ball setup, and neither are the same as a spherical bearing. A rod-end functions the same way... but Steeda uses a really tight and high end spherical bearing in their billet arms (only the 555-4406 set, the 4405's are all poly bushed).

This is sort of like calling every truck a "Mack Truck"--just because a design might use a ball for intended rotation it doesn't make it a rod-end, or spherical bearing, or roto-joint. They may share some characteristics, but aren't the same.

 

I recently tossed my spohn delsphere parts (upper CA and lower CA's) and went back to stock LCA's with J&M's 'poly ball' upper CA. The delsphere parts, while quieter than a classic rod-end still made a bit of noise (however nowhere near as much as a rod-end) and still have the harsh ride qualities of a solid joint-type mount. I've come to the conclusion that rod-end type parts just aren't for me on a daily driver. I've tried them all and they all make some kind of racket or turn the ride into crap over potholes, cracked pavement and the other things you encounter on city roads. I kept messing with spring rates/damper settings etc and all along it was the solid locators on my rear axle (upper/lower CA's) causing my disappointment. Once I went back to stock LCA's and the polyball UCA my ride is back to near stock but still handles very, very well with the springs, dampers, swaybars and watts link I have on the car. It's amazing how much ride comfort you give up for performance with the solid full-articulating parts.

That said, I tested the J&M 'poly ball' upper CA mount by running a long bolt through the mount and applying twisting force and can tell you...it binds more than a rod-end, extreme joint, delsphere or rotojoint type mount. It may give you some articulation over a solid poly but nowhere near what those other types give.