e36 5-lug sway bar options

[daniel]

thanks x10000 for your help.

i had strut bars on my old e30 but i felt much more of a difference once i installed the upgraded sway bars.

with fatty sway bars on the car, is it even worth it to add strut bars?

[Quailane]

Twice the stiffness in corners, or just in general?

the suspension isn't a stock M Roadster suspension, its an aftermarket H&R coilover kit (with specially matched bilsteins) made for the Z3M Roadster/Coupe. I have actually driven an M Roadster, and this suspension is definitely much firmer than the stock suspension.

should i look up the spring rates for this kit? would that help in finding a balanced set of sway bars? i tried to search for it in various websites but couldn't find anything. the model number is "29512-1". i found something that said 370F/400R. don't know if that is right though.

Oh, when you said you put on the suspension of an M roadster, I thought you meant a stock one. That is a big difference. By over twice the stiffness, I mean it would be like having a bar that is twice as resistant to twisting. It would be like if you put a 26mm front bar on your e in place of that 22mm bar. Another thing is that you also can't compare between E36 and E30 sizes because the lever arm of the swaybar is a different length, so seeing what can run on an M roadster doesn't do much good. I think I've seen up to 30mm on the E36. On rough roads a really stiff bar can be a problem because it resists the suspension's absorption of bumps. Your suspension should be able to use it though, and looking at that bar, it is very adjustable and hollow (slightly less stiff than a solid bar) so it sounds good for your car.

[daniel]

You can overdo sway bars. If the stock M roadster suspension is anything like the stock M3 suspension, it is relatively soft compared to aftermarket solutions, so I don't think getting the beefiest sway bars you can is the best idea. With a front 25mm bar, we are talking easily over twice the stiffness as you felt with a 22mm bar mounted to the control arms.

Twice the stiffness in corners, or just in general?

the suspension isn't a stock M Roadster suspension, its an aftermarket H&R coilover kit (with specially matched bilsteins) made for the Z3M Roadster/Coupe. I have actually driven an M Roadster, and this suspension is definitely much firmer than the stock suspension.

should i look up the spring rates for this kit? would that help in finding a balanced set of sway bars? i tried to search for it in various websites but couldn't find anything. the model number is "29512-1". i found something that said 370F/400R. don't know if that is right though.

[Quailane]

Actually, all of the e36s that I've ever bothered to check have had tube-mounted links.

Only cars produced up to about 2/'92 and M3's came from the factory with strut mounted swaybars. All others bolt to the control arm.

oops. i kind of fixed that post. anyway, i used to have the suspension techniques sway bar set (22/19), and there was a huge difference from the (i am guessing) 19/12 setup i had on my 325e.

the prices arent really a big deal since they are sort of all the same, I am just worried about possible adverse effects by going with the largest sway kit made for the e30.

i have read that the thicker the sway bars, the harder it is to sense the tires breaking loose when cornering, so it is more abrupt. i don't really remember straightline ride quality deteriorating with the upgraded sway bars on my old car, but they weren't as thick as 25/22.

anyone have any thoughts on this? i use my car as a DD, i drive it every day. i have never autocrossed or tracked it, but plan on it in the future. would sway bars be more worth more money than say, strut braces?

thanks to everyone who has contributed to this discussion. it always feels good to find a good answer to those questions floating around in my head.

You can overdo sway bars. If the stock M roadster suspension is anything like the stock M3 suspension, it is relatively soft compared to aftermarket solutions, so I don't think getting the beefiest sway bars you can is the best idea. With a front 25mm bar, we are talking easily over twice the stiffness as you felt with a 22mm bar mounted to the control arms.

[daniel]

Oh; the link was just to the home page so I assumed you were talking about the 22/19mm kit. It does make a difference, and i could feel the change with 20mm to 21mm, even with coilovers, but for the gain per $$, the IE kit is a bit pricey.

oops. i kind of fixed that post. anyway, i used to have the suspension techniques sway bar set (22/19), and there was a huge difference from the (i am guessing) 19/12 setup i had on my 325e.

the prices arent really a big deal since they are sort of all the same, I am just worried about possible adverse effects by going with the largest sway kit made for the e30.

i have read that the thicker the sway bars, the harder it is to sense the tires breaking loose when cornering, so it is more abrupt. i don't really remember straightline ride quality deteriorating with the upgraded sway bars on my old car, but they weren't as thick as 25/22.

anyone have any thoughts on this? i use my car as a DD, i drive it every day. i have never autocrossed or tracked it, but plan on it in the future. would sway bars be more worth more money than say, strut braces?

thanks to everyone who has contributed to this discussion. it always feels good to find a good answer to those questions floating around in my head.

[gearheadE30]

Oh; the link was just to the home page so I assumed you were talking about the 22/19mm kit. It does make a difference, and i could feel the change with 20mm to 21mm, even with coilovers, but for the gain per $$, the IE kit is a bit pricey.

[daniel]

Actually, all of the e36s that I've ever bothered to check have had tube-mounted links.

Your 325is has a 20mm front bar just FYI, so the IE kit won't be too different. If you want a bigger OE bar, the cabrios had a 21mm front. The best bang for the buck is to buy the tabs from AKGmotorsport and have them welded on. You will need e30 M3 drop links.

20mm to 25mm seems like a pretty big difference to me. 25% more bar.

whenever i do eventually upgrade the sway bars (probably not anytime soon), i will definitely be reinforcing every mounting point, front and rear. i had a rear mount break on another e30.

[gearheadE30]

Actually, all of the e36s that I've ever bothered to check have had tube-mounted links.

Your 325is has a 20mm front bar just FYI, so the IE kit won't be too different. If you want a bigger OE bar, the cabrios had a 21mm front. The best bang for the buck is to buy the tabs from AKGmotorsport and have them welded on. You will need e30 M3 drop links.

[daniel]

after a little more searching, i am now wondering what is overkill for a front bar.

should i just mount my current swaybar differently? or should i upgrade them?

this seems like a pretty good deal, and they include new adjustable end links.

edit: link is broken, but IE has a 25/22 kit for $440.

TMS has a 22/19 kit for $350 but doesnt include the extended links. and they arent 25/22.

[daniel]

I would get the E36 M3 ones (same part # as m roadster). The non-m E30 and E36 end links are the same part, so any difference between the E30 and E36 M3 ones would be in their length because of the strut. The E30 M3 ones would probably be shorter since it has a higher ride height. They are probably very close though since Turner sells the same adjustable end links for both cars.

cool, thanks. i guess i should've bought those instead of the stock e30 links i bought a few months ago and still havent installed.

[Quailane]

that is what i have gathered. i'm guessing the e30 m3 (rather than e36 m3) drop links are the ones to use, also.

I would get the E36 M3 ones (same part # as m roadster). The non-m E30 and E36 end links are the same part, so any difference between the E30 and E36 M3 ones would be in their length because of the strut. The E30 M3 ones would probably be shorter since it has a higher ride height. They are probably very close though since Turner sells the same adjustable end links for both cars.

[daniel]

Ya i was getting a little confused with the termonoligy but the meaning is the same.

E30 M3 mounting points> Non ///M E30 mounting points
Correct?

that is what i have gathered. i'm guessing the e30 m3 (rather than e36 m3) drop links are the ones to use, also.

[Wishno87]

no, it decreases the leverage the suspension travel has, which increases effectiveness of the sway bar.

Ya i was getting a little confused with the termonoligy but the meaning is the same.

E30 M3 mounting points> Non ///M E30 mounting points
Correct?

[daniel]

So are you saying that mounting the swap bar to the strut tube like on the E30 M cars decreases the effectiveness of the sway bar compared to mounting it to the control arm like on every other E30? Ive heard from many sources that the exact opposite is true. In fact i plan on making M3 style sway bar mounts with my stock vert bar in order to increase leverage.

no, it decreases the leverage the suspension travel has, which increases effectiveness of the sway bar.

[daniel]

Mounting a sway to the strut tube decreases, by a lot, the leverage that suspension travel has on the sway bar. You can run any E30 front sway bar, you just need the long front end links. An E36 bar is not going to fit. Also, you have E36 M3 front suspension, because those have the mounting tab on the strut itself.

Thanks a lot for your reply. I thought i remembered hearing that, but wanted to make sure.

i figured all e36's had the strut tube mounts, but they don't. but you are right, i have an M suspension. to be exact, they are H&R coilovers for the Z3M's.

because of the mounting points, I thought the actual swaybar needed might be different, but i guess not.

So the 20mm bar I currently had would immediately be more effective if i mounted it using the M3 drop links.

now the next question. i looked at TMS and they have the drop links for the e30 m3 listed separately from the e36 m3. which drop links do i use?