So why dont these exsist for our cars?
For those that dont know, they practically a cheap way to pinch/tighten up the rear subframe bushings resulting in a more solid feel.. Very popular/common in 240sx/300zx and numerous other cars.. can be setup for drift, drag or grip depending on how you install them..

http://www.czot.org/techtips/

example pics found on google



Please keep the comments about how rx7s are perfect and dont need such things toia minimum thanks. dont need another thead of people who dont do anything with thier cars suggest that these or suspension mods are not needed..

 

i think those are a bandaid fix for bad bushings. I dunno if they are still in business but i have solid subframe bushings in my car from MMR direct. You shouldn't need collars if you have those.

 

yah, but the collars are a cheap easy alternative and not as hardcore as solid bushings..

 

you just described at least 2 reasons not to do collars. i think uras does make pineapples for FC though

 

i'm fairly certain that alot of jdm drift cars use those things in addition to having good bushings. i could be wrong, but i don't think those collars are looked upon as bushing bandaids. they are used to tune rear wheel caster, subframe stiffness, and suspension center of gravity, all three of which can completely change the engineered characteristics of a cars dynamic....

 

well the fc has a subframe link to adjust camber and that kinda acts like a spacer would

 

Uras and Supernow make them for FC's

 

Subframe collars for S13

will solid mount the subframe WITHOUT removing the rubber bushings. it will compress the rubber and fill the gap between chassis and frame, bracket and frame.

the only advantage if this is that you dont have to remove the subframe from the car (just loosen it), you dont have to remove rubber bushings (can be pita) and collars are cheap.

Collars won't work on FC3S because the design of chassis/subframe is different. the rubber bushing is covered by metal from the bottom, there is no gap to fill.

DERLIN INSERTS or aluminum machined inserts (solid bushings). this is the right way of doing it. completely remove old rubber pieces and replace them with solid busings.

mmr-direct makes the for FC3S. many companies make them for S13.

 

thank you petex much appreciated for your knowledge

 

Who else besides mmr direct makes solid sub frame bushings?

 

Aren't the subframes (FD at least) already solid-mounted to the chassis??

Many cars isolate subframes with rubber bushings to for sound and road vibration deadening, thus replacing them with something solid will eliminate slop, but I'm pretty sure the FD subframes aren't "bushed"....

 

Many people say they dont like them because they are noisy (probably a clunking sound) but with a fully gutted car it's loud any way so... whatever.

 

the increased noise is what you hear of the forces going through the transmission and differential. If your car has full interior still. Its only slightly more noticeable. The gains in not having the subframe slop around while driving is well worth the increase in noise and ride firmness. For Nissans those collar inserts and those drift 'pineapples' are used to alter squat and anti-squat characteristics. For the nissan chassis if you are road racing or drifting dialing out as much anti-squat as possible is very helpful in gaining more rear traction.

I have the collars on my car, and I wish I had gone the route of the metal bushings. If you do solid mount them. make sure the trans mount and engine mounts are stiff, but not overly stiff (go no stiffer then a durometer rationg of 90-95 at the max).