Here is the new thread to avoid the total hijack of Mike Essa's thread that I caused lol.
As Mike asked, what is your tire/suspension setup?
But in general the E36 has a LOT of rear grip, and when you lower these cars they lose front grip, so they become even more rear grip biased. That's why most of the hot setups for roadracing include big rear bars and getting some front roll-center correction.
The problem is made even worse by cheap coilover companies not knowing ANYTHING about the platform and offering spring rate combos like 8kg/6kg or 8kg/8kg. The rear spring location on E30/E36/E46 means you need a much HIGHER rear rate than front in order to have a balanced feeling car, and it scares me to think these cheap suspension companies are likely valving their shocks inappropriately also considering the shock location.
Right now pro drifting has been moving toward much more rear grip bias which makes the cars faster while sliding, and they have to stay on throttle for smooth transitions like you mention, but it's very hard to learn from a basic level with a setup like that, and the car needs to be really dialed in to make it all work with the driver too.
Hope that helps you in the right direction,
Regards,
-Sean
.
.
.
.
.
https://www.google.com/search?q=e36+...ient=firefox-a
Some company I saw a couple years ago was selling 8kg/6kg also. Apparently some "engineers" don't understand "motion ratio" lol.
12/10 is really whack on an E36, or did you mean 10/12? Explain to people that the rear motion ratio is barely HALF of the front, so generally they need at least 30% stiffer in the rear. Look at PSS9's (very balanced setup) 460lb front, 680lb rear
.
.
.
.
Missed this earlier.
**All advice below is based on stock spring location**
**For true-coilover rear setups, I have no experience**
I generally recommend 50% stiffer in the rear than the front, so say youre running a 500 front, then run a 750 rear. Or if 8kg front, then 12kg rear. This is definitely my recommendation for an NA car and/or beginner. The car will have a natural balance and be easy to maintain a slide.
With 350+hp, and/or more advanced driver I'd say about 20% stiffer in the rear. Especially for competition drifting, where the rear grip will let you open a gap in the lead, and close the gap while following.
My stock PSS9's stock were a good balance for 190hp with 460lb front and 680 rear (thats 48% stiffer rear). I needed a 60mm front spring for my camber plates, and the closest thing the local shop had in the right length was a 400lb. I wanted to go stiffer, but it felt fine and I never changed it.
Even with 400lb front and 680lb rear though, (70% stiffer rear) The Z-link just put the power down so well that none of the local cars with more hp could keep up in tandem, and my car was only on 235 Dunlop Z1's
Now for reference, my E36 weighs 2550lb, and I never drove the car in full weight trim. At it's first event it was 2720lb.
Also as you lower Any E30-E46, the front loses grip more than the rear (due to roll-center and camber curve), so these cars become even more under-steer prone as you lower them unless you get some front roll-center correction.
And remember, for street tires, (regulation 140UTQG) high spring rates just do not get the most grip out of the tire. For static drop on stanced cars you need a stiff rate, but for maximum performance on a competition drift car you are probably looking at a 350-400lb front spring and maybe a 450-500 rear.
For race cars on slicks and R-comps, the tires generate so much more lateral grip that they get much more weight transfer. On soft springs this would cause too much camber change and body-roll, so they run much stiffer rates. Also the sticky slicks with good shocks will hang in there at much higher rates before breaking loose.
~~~~~~~~~~~~~~~~~~~~~~~~~~~MERGED POST~~~~~~~~~~~~~~~~~~~~~~~~~~~
MORE TECH:
E30/E30/E46 front motion ratio: .94 (the spring moves 94% of whatever distance the wheel moves)
E36/E46 rear: .65
E30 rear: .67
Now to get your effective spring rate, you need to square the motion ratio (because after the spring compresses, it has to push against the lever arm in order to rebound the wheel) and then multiply that times your spring rate.
The actual force the wheel sees, is called the wheel-rate.
E30/36/46 front: .94^2 = .88 (1000lb spring gives 880lb wheel-rate)
E36/46 rear: .65^2 = .423 (1000lb spring gives 423lb wheel rate)
E30 rear: .67^2 = .45 (1000lb spring gives 450lb wheel rate)
The rear end has BARELY HALF of the EFFECTIVE spring rate than the front for E30, and LESS THAN HALF on an E36/46 for an identical SPRING rate!
From corner balancing my own car, I know my weight distribution is 52/48 (it was better stock, but when stripping a car, a lot more tends to come out of the rear)
Now for a perfectly balanced setup in theory, when we add the front and rear WHEEL RATES the front should account for about 52% and the rear should make up roughly 48%.
Lets try this for a known setup (PSS9, and no I don't work for Bilstein! lol)
Wheel rates:
F: 460*.88 = 405lb
R: 680*.423 = 287lb
So even though the 680lb spring rate seems huge, it's really only a 287lb at the TIRE. Lower your wheel offset, and it goes down even more!
Now lets add them 405+287=692lb and figure out how much of the balance each makes up.
405/692 = .585 (405lb is 58.5% of 692)
287/692 = .415 aka 41.5%
So since the wheel rate is 58.5/41.5 biased to the front, the front is effectively STIFFER than the rear relative to the 52/48 weight distribution which should provide understeer at the limit (logical for an off-the-shelf coilover).
Here's a few combinations put through the E36/46 calculations above:
8kg/8kg = wheel rates: 7.04kg/3.4kg (67/33 distribution)
10kg/12kg = wheel rates: 8.8kg/5.1kg (63/37 distribution)
12kg/10kg = wheel rates: 10.6kg/4.2kg (72/28 distribution)
10kg/14kg = wheel rates: 8.8kg/5.9 (60/40 distribution)
10kg/16kg = wheel rates: 8.8kg/6.8kg (56/44 distribution)
Last edited by SLR; 01-06-2013 at 08:20 AM. Reason: Automerged Doublepost
Very good info thanks a bunch, was just thinking about changing my spring rates have alot more roll now with the slr setup(especially in the front) which i think is due to not having the sway bar and wider stance. Right now im at 8/10k going to try putting the sway bar on but heard if you mount it to the arms it loses performance and almost need a stiffer sway bar to counter act it.
1993 318i L33/T56 Swapped Drift Thingy L33 Blew Up Time For LS2
For the record, I run 10/18 on the drift E30 and people that didn't know called it "soft"
Status: Someone put glitter in my oil. Wait. Why's all my oil outside the engine? What's that knocking?
I was just looking through a few catalogs seeing if I can find a simple bracket setup. I think I found a panhard bracket that should work, you'll just need heim end links.
Did you try running your bar strut-mount yet and see what you think? Would still need some kind of heim type end link with end loose to give you full angle.
Na i didnt try it i had it on but around full lock it would bind up so took it off. I found some tabs to weld on but not sure if its going to be strong enough. Think if i had a front sway bar the car would be money if not then go a little stiffer on springs. Once i get may car back from being caged im going to play with it.
1993 318i L33/T56 Swapped Drift Thingy L33 Blew Up Time For LS2
Technically it's not a strut, but a coilover shock/spring. Struts are a spindle that is bolted or welded directly to the shock so the shock becomes a load bearing suspension component which maintains camber/caster.
Technicalities aside though, it's probably very similar to E30 and E36 rear shock motion ratio which is 1.05
Wheel rate is 1.05^2 which makes 1.1
Last edited by SLR; 01-06-2013 at 07:58 PM.
Good Info... !
Sean, I have a E36 sedan N/A 228whp, it weights 2,570, I have K-sport 9kg/12kg.
Q: If I run with out the front Sway bar, I get or loose front grip ?
also, if the car is lower in the back than in the front , do I get to go faster ?
Last edited by Juanchy; 01-06-2013 at 09:56 PM.
I run 10kg front and 12kg on the rear and i feel i can go i little more little stiffer on the back but at the same time i wondering how the car will react on transitions???
How much anti-roll bar you need depends on a lot of things. Generally you will lose front grip due to lack of weight transfer and you will lose turn-in feel also. With roll-center correction and wider arms you can get away with less anti-roll bar, but it will always feel soft on turn-in so you have to throw the car into a slide more.
For ride height, E36's can look lower in the back because of the low fender lip, even when they are perfectly level. Generally the rear should be about 5-20mm higher in back when measured from the bottom of the rocker panel.
Status: Someone put glitter in my oil. Wait. Why's all my oil outside the engine? What's that knocking?
Bilstein does subscribe to that, but it is worth noting that GC, TCK, and many other only raise the rear rates about 100lbs or roughly 2k. I personally use that bias but have a higher HP car. if it was a little warmer, id set up a trial of a few different combinations, for science.
Last edited by Jaze; 01-07-2013 at 08:45 AM.
any decent drift operation has a handful of different spring rates to dial in the car for different surfaces, temperatures, tire sizes, course layouts, etc.
I have never known any sort of information on spring rates....ever....and now my mind is blown. I realize now that I have been a terrible car guy/drifter and just slap stuff on without knowing anything about it and just run it.
I thank you all for giving me such valuable knowledge.
get an alignment, it will change your life.
so tired of drift kids throwing on parts, and never actually aligning anything, ever.
Yea I held off on getting one on my last car because I kept damaging suspension components/shell from dirt drops and wall hits.
Once I finish building the new car it is the first thing on my list
I wouldn't even bother until you upgrade from those dumpy racelands
I got a laser alignment then broke a tie rod the next week lol. Now I mainly use measuring tapes between alignment sessions.
Status: Someone put glitter in my oil. Wait. Why's all my oil outside the engine? What's that knocking?
ok, Thnx.
I forgot to tell U I'm using E46 arms and fixed knuckles. I run NO front sway bar because when full lock the sway bar links were touching the side of the chock and making the steering felt inaccurate and weird. I wanted to know wish way was better, thats why I asked.
*sorry for my bad english, I speak spanish ;-)
Hmm, what do you mean by chock?
gotcha!
You cars only have non-m listed, but do your endlinks connect to the control arm or the strut housing (m3 struts)?
Juanchy, por que no usas la Non M sway bar end links? Yo no se si tu lo quiere por razones de preferencia pero a mi me da lo mismo. El sway bar non M es mas grueso, tu esta usando el non M sway bar con los M3 end links? por que eso me ha dado problema en el pasado con ruido de la suspension.
Last edited by Jaze; 01-07-2013 at 05:57 PM.
Yo no hablaba nada de espaņol, pero utilizando un traductor me hace ver como un puto genio.
'98 328 S/C'd Driftorito
Bookmarks