# b13 rear susp. VS b14 rear



## StevenLK (Jul 15, 2002)

i know hardly anything about suspension but what i was wondering is why do people say that the B13 Rear suspension/set up is better than the b14's? 
something to do with independent axles or whatever? 

-just wondering thanks!


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## pete? (Jul 6, 2004)

the b14 rear is a solid beam, the b13 rear has independent suspension. the solid beam sucks because if one wheel moves the other will too, so it will through the camper off on the opposite side. the independent is better because if one wheel goes into a pot hole, or hits a bump in the road, the opposite wheel will be able to do its own thing and be unaffected. hope that helps


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## ReVerm (Jan 13, 2003)

1.6pete said:


> the b14 rear is a solid beam, the b13 rear has independent suspension. the solid beam sucks because if one wheel moves the other will too, so it will through the camper off on the opposite side. the independent is better because if one wheel goes into a pot hole, or hits a bump in the road, the opposite wheel will be able to do its own thing and be unaffected. hope that helps


It's actually not that simple.

Sure, independent suspension is great, but it also brings in a whole slew of problems that have only recently been addressed in affordable production cars. One such problem is this phenomenon called "bump steer", which in broad strokes, describes a sudden change in toe that occurs when a wheel attached to an independent suspension system moves up/down (like when you hit a bump). This is not as serious a problem in the front end of the car because the driver can compensate for this via the steering wheel. But the driver has no control over the toe angles on the rear end of a car (like the rear end of a B13). Bump steer can therefore cause instability in a car with a simple independent rear suspension system.* Cars with a solid rear axle (like the B14/B15) do not suffer from this problem.

Independent rear suspension systems also suffer from dynamic camber changes more because of the fact that control arms attached to rubber (or polyurethane) bushings need to be used. Wheels attached to a solid axle, on the other hand, are able to push against a big metal beam. In the case of the B14/B15, that big metal beam is attached at two points to the chassis, which means little to no flexing and very little of the aforementioned camber trouble.

Of course, I am not saying by any means that solid rear beams are a better solution than independent rear suspension systems. I am also not saying that all independent or dependant suspension systems act the same way in all situations. I am simply trying to keep people from getting the idea that independent > dependant in all situations and to keep anyone from wasting money on a B13 rear suspension swap for a later model chassis.

_*Notice that I put the word "simple" in there. This is because some manufacturers have started designing their passenger car suspension systems to mitigate or even eliminate some of these problems. The current generation Civic Si, and the upcoming generation Civic variants, for example, all use a very interesting macpherson strut/multi-link (depending on the car) system for both the front and rear to eliminate the bump steer problem._


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## StevenLK (Jul 15, 2002)

i some what understand it better now. i was just wondering because i see people saying b14 is better then b13 is better and was curious whats the big deal...

-thanks 4 the info


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## viprdude (Jun 27, 2003)

the b14 beam does not suck. it is all over se-r.net that mr kojima himself has wrote about this many times. here is a part of what mike wrote on the site about the b14 comparing it the b13.

" am writing to defend the beam axle of the 200SX once and for all! I have owned and raced classics in SCCA and IMSA quite a bit. I also own a 200SX (SCC Magazine Project SE-R). I feel that both are fine handling cars. 

Stock on stock the classic rotates a little better under lift throttle which is advantageous for racing, especially Solo II type stuff and the 200SX pushes a bit more making it a bit more forgiving. The difference is pretty difficult for most people to tell, rather subtle. 

The beam on the 200SX is rather sophisticated for a beam, being a twist link that allows independent action of the wheels. It also has a lateral link to lower the roll center and for lateral location. The advantage over the classic being no toe, camber or bump steer change under roll, so as not to make as much trailing throttle oversteer. The bushings have minimal stiction, combined with the twisting of the beam make for a tramp free ride even under cornering load on rough surfaces.

This is not at all like the crappy beam on cars like the Paseo, Tercel and American cars. It really works. When modified the SX will outcorner about anything. Searl whooped up on lots of Porsches and every classic on street tires at a time trial track event in his SX. My car handles better in some ways than my super trick 300zxtt. I am not biased but have a lot of experience with both cars." -Mike Kojima

stock for stock a b13 is slightly, only slightly better thna a b14. if you want my opinion, given the physics that i know in a car when driving, having a beam in the rear is better for a FWD car because those rear wheels should flex in every angle as little as possible and a IRS on a b13 allows much flex in the rear wheels for a FWD car. The best setup for a FWD that I believe is a version of the G20 (forget if its p10 or p11) because they have the best front setup with the rear beam. enjoy!


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## pete? (Jul 6, 2004)

^ nice find! so imguessing my future setup (agx b13front, hyperco, motiv mount, koni bumps, and rear sway bar) will be an outstanding ride? good to know! im liking my b14 more and more....now to fix those bloody door panels.


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