Wow, we have a SE forum!:D

Anyways, I've been doing quite a bit of research, development (well, not really) and such over the B15 suspension and... as most of you know... it's damn frustrating! No one really knows for sure (with any real confidence and reasoning to back it up) what the B15 really needs on all corners to handle ideally.

This leads me to my question(s)... Mostly aimed at you SE-L guys. I need to know how your car handles. Particularly with AM setups and mainly coilovers at that. I need to know detailed description of how the car acts in different situations and what your spring rates are. Damper description would be nice too.

But any B14 can comment. I'm trying to do a semi detailed comparison of the two platforms to form some theories. I'm weird like that maybe, but oh well!:D

Thanks in advance SE-L dudes and all of you!

In my opion the hot setup on a b14 would be a 300/250 combo with the adjustable stillen rear bar, stock front swaybar, some koni's/agx's and STB's. I think this with a beam corrected for zero toe would rule. I think that 275 might be better with the beam no bent. I have a 300/200 setup and really want a bit more rotation then I have. Other then that I just described my basic setup and it is pretty good for street, autocross and roadcourse work. On a b15 I would increase the rates about 50lbs and go even front and back.

I have the motivational (konis) with 350F, 300R. GC C/C plates -1.5deg, 2mm toe out.
Stock front sway bar with ES bushings.
Front control arm bushings.
Stillen adjustable rear sway bar.
Courtesy F&R strut bars.

The sway bar has three settings (maybe 4, if front-in back-out is different than front-out back-in (that makes sense of you have the bar)). With the sway bar in the intermediate setting, the car was too tail happy on a fast autocross course with no weight in the back. I was going to try this weekend on the soft setting, but the columbus autocross was cancelled. On a slow autocross with weight in the back and a poorer front alignment it was understeering. But remember, I have no LSD, yet.

I have a quiafe, plates, and and a full bushing set also. I shotrtened my own struts ala motivational. I have mine full stiff in back. I like oversteer on a autocross. Personally, i would buy two sets of springs for autocrossing vs roadcourse work. I have aslo toyed with the idea of the increased front bar and even stiffer rear springs. I have a quaife so traction on the inside front tire is not that big of a deal. Maybe a 350/350 with a ST front and the Stillen rear bar.

Originally posted by 98sr20ve
I like oversteer on a autocross.

I'll rephrase. i spun twice, early in the course, on drop throttle. I have no driving practice with anything except understeer, so this was new to me. Maybe it was a good setup, maybe it was too tail happy. I need more practice to figure it out.
There is no way I would have taken the car like that to a road course, though.

PS: nice post count ;)

Thanks for the responses guys. I'm still sorting through some of the other suspension parts you guys have as some are not available to the B15's, and I'm just plain not familiar with them!

The reason I'm asking is that (as I said) I'm trying to theorize on the ideal B15 setup. Kojima had stated (in his suspension article) that he "thought" the B15 should have more rear spring rate "perhaps because of the longer wheelbase". Well, it turns out that our 99.8" wheelbase is the same as all of the rest of you, so that's moot. Weight is my next concern. The SE-L has almost identical specs (other than F/R weight dist. which I'm not hip to yet, anyone help?) as the B15. That's why I'm aiming at them.

My suspicion is that we (b15's) don't in fact need such high rear rates as everyone thinks (50lbs/in HIGHER rear than front). THe Spec-V with it's stiffer rear axle and 50lb/in higher rear rates tends to be loose from my sources. SO I'm thinking... even rates plus ARB and possibly STB in the rear and wala! I dunno. The Moti guys with the 350/350 rates (plus ARB and STB {some}) seem to be neutral until they want it to come around back there.

Well, okay, hopefully I get more posts/insight. Thanks again.

Check out the sig theres my setup. Eventually I'll switch to AGXs or Konis or Motivational. The car holds good during hard cornering etc.. with more understeer than oversteer with my setup I still havent gotten around to throwing in the ES bushings for control arm

What rates on the GC's though? Damn I was hoping to have more response and opinions on the B15 setup. The thing is, everyone says "I would do this" or "I think this" but no one can say scientifically (rationally, logically, etc.) why! I know it's new, but it's all physics. We know the numbers on the car, so let's plug in the formulas and come up with something.

what are the alignment specs on the rear of your car?

Originally posted by tredragon
What rates on the GC's though? Damn I was hoping to have more response and opinions on the B15 setup. The thing is, everyone says "I would do this" or "I think this" but no one can say scientifically (rationally, logically, etc.) why! I know it's new, but it's all physics. We know the numbers on the car, so let's plug in the formulas and come up with something.

I think you are asking a bit much. Science. It is all just personal preference to a degree. I ran 3 degrees negative camber on a oval today. I had massive oversteer with this setup. It was unreal.

Firstly, there are no alignment adjustments possible on the rear short of a bottle jack and a bending jig. It's an axle.

Secondly, I'm not trying to find exact answes just yet. Merely what people are running the in the similar SE-L (weight wise anyways) and also some input on what people think, but with the "WHY" too!! We have the same wheelbase, higher weight (than B14's other than the SE-L) and close to the same dist. F/R. Yet the B15 is "recommended" to have higher spring rates in the rear than front, which is the opposite extreme compared to B14's. I'm trying to figure out what (if anything) really changed that much.

Hell, I'm just trying to come up with a good logic in my head to decide on what I need suspension wise. I have the coilover research done for the most part, now it's just a mattter of spring rates....

Originally posted by tredragon
Firstly, there are no alignment adjustments possible on the rear short of a bottle jack and a bending jig. It's an axle.



I was referring to the front.

I too am curious why the B14 crowd was given a 300/200 recipe and the b15 crowd the 300/300. Personally I think it is two possible things. The first is that the 300/200 was developed back in 97 ish with Mike K and his car. As time has progressed I think that some people have become less conservative and have been willing to put higher rate springs in the back. Second, I would be real interested what the toe and camber specs are on the B14 and B15 beam. I wonder if they are different and that in some way influenced the choice of spring rates. Personally I would prefer higher rear rates on my B14 and I have the stock front bar and Mike is running an upgraded front bar. I am sure his car is not near as tail happy as my current setup (which I will now adjust a bit due to the negative camber up front).

Originally posted by tredragon
Firstly, there are no alignment adjustments possible on the rear short of a bottle jack and a bending jig. It's an axle.


Yes, I know. But the settings are still important. I don't know if the B15 retains the same conservative toe-in that the B14s have or not. Maybe it has more or less toe-in. Maybe its the same...

I don't have a 4 door B14, but with 325/200 GCs, the car still understeered. My setup is AGXs,325/200GCs, was front and rear STBs, now just rear, N-tech lower brace, ST rear sway bar, stock front sway bar. I switched to 325lb springs in the rear, and that helped give some oversteer. On the street, the 325s are no different than the 200s were. I have new AGXs (b13 front, B14 rear), and Motivational rear plates to install when I get around to it. My rear axle still has the 3" toe in Nissan was so good in giving us, so I think B14/B15 owners need a higher rear spring rate than 200. Ground Control now sells their kit with 325/250 springs, if this is an indication of the change in research they are doing. I drove a Spec V at the convention, and it was very neutral with 3 people in it. I think for a B15, spring rates slightly higher than the Spec V would be nice. The Spec V also has a thicker rear axle, so you would need to take this into account.

[QUOTE]Originally posted by tredragon
[B]What rates on the GC's though? ]

ahhhh I think they are 300front 275rear I may be wrong something like that

Not particularly the specific poundage, but more the ratio of F/R is what I'm after. It just seems funny to me that B14's run at least 50lbs/in (some 100+) higher in the front and the B15's run 50 higher in the rear, or even rates.