As many S-Chassis owners out there know, the subframe bushings of Nissan S13 & S14s are made of yummy-gummy rubber from the factory primarily because regular drivers demand and want comfort along with sportscar sportiness to go along with it too. With the S13/S14 chassis being long in the tooth (a.k.a. OLD and possibly ancient) however, the rubber bushings of the subframe deteriorate over time during its use and in some cases, it gets so bad that the car moves like Shakira’s hips over bumps when switching lanes on the highway; the subframe moves one way and the chassis the other. Believe me I know because I have driven an S13 with really bad subframe bushings which was downright scary.
So what’s the solution? The options are: 1. New oem rubber bushings (which will still wear out and have slop ) 2. Subframe collars (stopgap measure and rubber bushings will still flex) or 3. Set of new poly inserts (good but needs greasing). Now while all these solutions may be good choices, they will either wear out over time or need maintenance and you will probably end up in the same place where you started. To avoid those maladies, pressing in a set of DIF solid aluminum bushings is an excellent alternative and choice that needs mostly no maintenance and gives the most performance gain out of all.
While the OEM rubber subframe bushings do the job of keeping the subframe in place with the chassis, their performance limitation is evident when pushing the car to its limits and beyond. And when the bushings do go bye-bye, they almost certainly have to be replaced.
The solid bushings, when compared to rubber, will not wear out which gives you longevity and reliability along with the benefit of needing no greasing in the future like poly inserts. Additionally, they will not deflect as rubber would at all when pushing the limits on the twisties or roaring down the race track straights. This in turn inspires driver confidence in pushing the car as it now would react consistently and predictably.
*NOTE*: This is NOT for the inexperienced or lazy. Be prepared to spend at least a whole day to upwards of two days to get this done from start to finish.
Install page here: DIF Offset Center Solid Bushing Install on a Nissan S13 240SX
When driving the car around the block for the first time with the new solid bushings installed, there was a noticeable difference in how the car accelerated, sounded, and felt; it is now more of a visceral thrill in that you can feel things coming that much more from the rear.
The whole car has that more “connected” feeling instead of the disjointed, mushy one with the rubber bushings. I myself expected my brain to be rattled around along with my kidneys bruised but surprisingly, the ride was not compromised to that extent. Aside from the LOUDER noises, the mechanical symphony that plays from behind is actually quite soothing in a car-guy sort of way.
About the biggest difference is how the rear now plants and digs in coming out of corners which was really noticeable during my last autocross practice/competition round. With the rubber bushings before, the rear would have that sloppiness to it where I would have to wait for it to plant and stabilize and then put my foot down on the gas to power out of the corner. If I timed it right, the rear end would be settled enough with a slight slide on corner exit BUT if I timed it wrong, the rear end would step-out a little too much which resulted in time being lost.
With the solid bushings, I can now feed the power more quickly out of the corner due to the increased tightness of the rear which has resulted in more overall rear-end grip. Translation: I can mash on the throttle MUCH MORE harder and not have it step out too much which gives me more control over the car.
If Nissan really wanted to make a “pure” race car out of the 240sx, they maybe would have made all the bushings out of metal and then you’d have to wear a mouth-guard to protect your teeth. Fortunately for some (regular drivers) the rubber bushings in the rear subframe do the job adequately BUT unfortunately for others (sports car/racing enthusiasts), it’s not enough to outdo the performance benefits that solid aluminum does for a 20+ year old chassis.
So, if you want to do the job right the first time in order to get the maximum performance out of your S13/S14 and make sure the rear end doesn’t do the “macarena” anymore, then press in a set of DIF solid billet aluminum bushings. The car will ultimately be more European-Sportscar solid and mashing down on the pedal to power out of a corner will feel both exhilarating and satisfying, especially when you leave the competition behind in your tire tracks.