What barrel spring lengths for E36

[hc1001]

Hi,

Im looking to go with stiffer springs for my E36 M3 HPDE/street car. Currently running TC Kline 450f/500r on my KW V3 coilovers. My ride height is around 13"F 12"R, fender to center hub cap.

Im thinking of a very slight bump to hyperco 500F/550R springs or should i go 500F/600R? I think im limited to 6" for the fronts but wonder what length i should get for the rear combined with the KW height adjuster. Is 5.5" too short? Is 6" okay?

Im perfectly happy with my current springs but they need to be replaced due to age, and corrosion. I thought a slight bump in rates would be a good idea. I've read the TC kline beehive design is superior to the barrel design but see many users using the barrel in the rear without issues. I will use the nylon spring alignment platform combined with the KW height adjuster. Is the articulating spring perch a must?

Also when going to stiffer springs, as a general rule of thumb, do you soften compression from the current settings?

Thanks for any help.

[aeronaut]

Where are your height adjusters currently on the front? If you have room left to lower, then 6" will probably be ok when you add 50lb/in.

Lots of folks run non-behive in the rear with no problem, especially higher rate springs as they are less likely to go to full compression.

I have TCK SAs C/O's, 550/650 springs, and 6" springs work well.

As far as spring rate split front to rear, it all depends on which ARBs you're using and what you want the car to do.

What tires are you running?

[hc1001]

Where are your height adjusters currently on the front? If you have room left to lower, then 6" will probably be ok when you add 50lb/in.

Lots of folks run non-behive in the rear with no problem, especially higher rate springs as they are less likely to go to full compression.

I have TCK SAs C/O's, 550/650 springs, and 6" springs work well.

As far as spring rate split front to rear, it all depends on which ARBs you're using and what you want the car to do.

What tires are you running?

Hi,

Thanks for the reply. Yes the 6" fronts should be fine. Im currently running 6" and tender springs but will ditch it to raise the spring perches to fit some 255 tires hopefully.

Im using UUC sways. The 450/500 im currently running have felt great so i guess i will stick to the 50# difference.

What is your ride height with the 6" spring in the rear and where are your adjusters currently? I just wanted to make sure i choose a rear spring that wont be too short or too long.

Will be running RE71R.

[TXBDan]

Remember with the motion ratio of the rear, a 50lb spring rate change is like half that at the wheel.

I went from 450/500 to 500/600 and its stiffer, but not by much. I'm running 60mm x 6" springs front and rear. My rears do fall off the delrin perches some times, so gotta keep an eye on it. I'm using the stock TCK rear spring height adjusters.

[hc1001]

Remember with the motion ratio of the rear, a 50lb spring rate change is like half that at the wheel.

I went from 450/500 to 500/600 and its stiffer, but not by much. I'm running 60mm x 6" springs front and rear. My rears do fall off the delrin perches some times, so gotta keep an eye on it. I'm using the stock TCK rear spring height adjusters.

Thanks for your input Dan. Yea, i suspect the rear springs may pop out at full droop with this setup.

I ordered 500/550, both 6" since it seems a lot of ppl are using 6" in the rear without height adjustment issues. I run a staggered wheel setup and will be going square next season. 18x8F/18x9R to 18x9 all around. The square setup will induce oversteer, so the 500F/550R springs will induce understeer. Im not sure how much effect each change will make until i take the car out with the new setup. I can fine tune it from there. Hopefully its not drastic.

[hc1001]

Hmm i think i should've gotten 500/600 now...

[Crustashio]

I went from 350/400 to 500/600, and will likely go to 500/650. 500/600 is still quite pushy but I am using a big front bar to minimize camber loss in roll.

[hc1001]

Thanks i decided to go with 500/600#.

Are you running a 6" spring in the rear? Does your height adjuster have good adjustment range?

[Crustashio]

Running the TCK 600# beehive springs on their adjusters. Probably have abut 1/2" left on the adjuster to raise the car, and about 1" left to lower it. I don't have my ride height measurements handy but it's got a bit of rake F/R.

[badmonkey]

I went from 350/400 to 500/600, and will likely go to 500/650. 500/600 is still quite pushy but I am using a big front bar to minimize camber loss in roll.

500/650 with big front bar is a good setup that’s still streetable. 650 is a touch too much for an off the shelf Koni, imo. Not horrible, just felt under damped.

[aeronaut]

FYI, with 550/650, I backed off from full stiff to full soft on my UUC front bar, and it reduced understeer a touch and made my car a touch more neutral.

[ThreeD]

FYI, with 550/650, I backed off from full stiff to full soft on my UUC front bar, and it reduced understeer a touch and made my car a touch more neutral.

Same here. Lost a little bit of sharpness in turn in, but steady state dynamics are much more neutral. With the front bar at full stiff it would rotate on entry if I pitched it, but then the bar would pull the front end straight mid corner/understeer.

Sent from my Nexus 5X using Tapatalk