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beckley
08-12-2006, 10:27 PM
i have an 87 325i with 90,000 miles on it and it's time to change the shocks. i was thinking about doing the "lower the car by installing sport shocks and sport springs" thing, but have been told by several people that the ride is way too harsh for driving around town (i don't track the car, but do autocross it).
i've decided to install some bilstein touring shocks, which are supposedly stiffer than the oem shocks but softer than the bilstein sport shocks. my question is how long do the stock springs usually last? seeing as i'm at 90k miles, can i expect them to need replacing soon?
if i do need to replace them, is there someone that makes a stiffer spring than the stock ones that won't drop the height of the car?

thanks,
jim

jkuper
08-13-2006, 03:31 PM
Bilstein touring are like 5% more, I think they are designed to run an OEM spring at OEM ride height.

OwnedbyDuncan
08-13-2006, 05:01 PM
I would run Bilstein HD's with either a stock is spring or a stock E30M3 spring. Be wary of most of Eibach's offerings for the E30325 since in many cases they are not as stiff as the OEM.

HDs are for stock ride height on a e30 and Sport for lowered ride height. They are valved the same.

Eibach used to make and may still make a nice set of anti sway bars for the E30325. They aren't too big where you would have to worry about ripping out the mounts because of soft springs.

Car is old I would replace the control arms, tie arms and all the bushings while things are apart. Also get the car aligned. Age not mileage has taken its toll.

SharkD
08-13-2006, 07:05 PM
I might suggest looking at the SpecE30 suspension -- it slightly lowers the car and is pretty neutral, though it may be too stiff for your taste.

beckley
08-14-2006, 05:00 AM
i get why i should change out the bushings (rubber breaking down after so many years), but why the control arms and the tie rods? they're metal and should be ok, unless they are damaged structurally. what am i missing here?

thanks,
jim

OwnedbyDuncan
08-14-2006, 05:38 AM
Control arms on E30's fail. They crack. One of the few weaknesses on the car. It is also easier to replace the control arm than just the bushings. Tie rods deteriorate with both age and mileage. I know owners who use their E30s in drivers schools who replace the control arms at least once a season.
If you have everything apart now is the time to take care of things. Also take a close look at the front subframe for cracks.

Engine mounts will probably need to be replaced. Alternator especially if it is not a Bosch unit. If it is a Valeo you are on borrowed time. I would also replace the fuel pump if it hasnt been replaced already.

Consider a short shift kit for the car since it is alot easier ton install than the individual bushings.

Dave Apker and the collies

AlfaEric
08-14-2006, 08:15 AM
Since you autocross, just ask people with E30's to give you a quick ride and ask what they have done with their suspension.

---Eric

ErikT
08-14-2006, 08:21 AM
My E30 (1990 325i) has H&R springs with Billstein shocks & a front strut brace. The parts were installed when I bought the car but I've been using it as a daily driver without any regrets.

I'm guessing it rides about 2" lower than stock. Big bumps are a little rough, but my commute is all highway so it doesn't bother me at all.

Asking the autocross guys is probably the best idea, but since you're in bethesda you are free to take a look at my setup and I can drive you around the block. Send me a PM if you like.

SharkD
08-14-2006, 09:27 AM
E30 control arms (they bend), tie rods (they bend and/or rust), wheel bearings (they can catastrophically fail) and timing belts are extended mileage wear items. They should be replaced at regular intervals (between 20,000-50,000 miles; depending). If you track the car, they should be replaced, at the least, once every two years, many racers and HPDE regulars change them annually.

On 1987 and earlier 'i' cars (there aren't any U.S. pre-87, though), Motor Mounts should be inspected religiously -- when they fail, the mechanical fan will slice the upper radiator hose. I would suggest swapping the stock engine and transmission mounts for Ireland Engineering or similar Urethane Mounts. BTW, even if the mounts "look" okay (mine did) the will probably disintegrate when removed, like mine did.

Scotty
08-14-2006, 03:51 PM
On 1987 and earlier 'i' cars (there aren't any U.S. pre-87, though), Motor Mounts should be inspected religiously -- when they fail, the mechanical fan will slice the upper radiator hose. I would suggest swapping the stock engine and transmission mounts for Ireland Engineering or similar Urethane Mounts. BTW, even if the mounts "look" okay (mine did) the will probably disintegrate when removed, like mine did.

My motor mounts were broken when I bought my ('87) car. I don't know how many miles were put on the car after they broke, but the wear was on the lower hose due to the steering pump pulley.

Strangely, the radiator bypass hose also came into contact with the fan. Strange, because this hose never leaves the engine - it goes from the thermostat housing to the water pump. I think it came in contact with the fan because of a broken hold-down bracket on the manifold was missing.

beckley
08-18-2006, 10:01 AM
geez, all i wanted to do was replace some crappy shocks! seriously, though, thanks for all of the responses. i'll be at the do-it-yourself event at convenience car care next weekend and will ask the guys there what they think i need to replace. hopefully the laundry list of parts won't bankrupt me.

thanks again,
jim

1996 328ti
08-18-2006, 06:15 PM
I'll be at CCC too with my new E30.
Rotors, brakes and maybe shift lever.
Oh, and oil.

ErikT
08-21-2006, 08:38 AM
I'll also be at the DIY. I'll have to take a look at the motor mounts on my "new" E30 as well.

beckley
08-26-2006, 08:50 PM
well, good news. john at ccc took a look at the suspension components and the only thing that he recommended replacing were the rearmost control arm bushings (the "lollipops"). i had already planned on swapping out the shocks and springs, and he confirmed the need to do this.
see how much money these diy events can save an amateur like me?

M-technik-3
08-26-2006, 09:37 PM
Common E30 failure as they get older. Replace them with E30 M3 CAB. CAB = Control Arm Bushings.

beckley
08-27-2006, 06:04 PM
are these polyurethane (or a like material) bushings? i had a couple of guys at the diy tell me that they regretted going to the polyurethane as it made the ride SO much harsher.

beckley
08-27-2006, 06:13 PM
are these polyurethane (or a like material) bushings? i had a couple of guys at the diy tell me that they regretted going to the polyurethane as it made the ride SO much harsher.

M-technik-3
08-27-2006, 08:09 PM
No they are factory oem rubber, but they are more durable.