[sav_e92]

I'm looking for some guidance on the next steps to improve the suspension of my 328xi (e92). I drove in my first autocross event last weekend and while the car handled well, I did notice a fair amount of body roll and could feel it pushing pretty hard through the turns. I'd like to see what I can do to keep the car flatter and balance out the understeer a bit. I have Koni Yellows installed (about a year old now) and ran those at a full turn off of full soft front and rear during the race. I also noticed a fair amount of dive/squat that I'd like to mellow out.

My thoughts on options are:
Lowering springs - would likely do H&R as from what I can tell, they're the stiffest and provide a reasonable drop (wouldn't hurt to fix the ole' xdrive rake too)

Sway bar(s) - what would the right combo be here? Stiffer rear bar?

Bushings/control arms refresh, etc. ? My car has about 96k on it but I've had the suspension inspected recently and nothing was noted to be busted... though I'm sure new bushings would feel nice.

What will make the biggest improvement?

[edycol]

Originally Posted by SAVAGE_VT_E92

I'm looking for some guidance on the next steps to improve the suspension of my 328xi (e92). I drove in my first autocross event last weekend and while the car handled well, I did notice a fair amount of body roll and could feel it pushing pretty hard through the turns. I'd like to see what I can do to keep the car flatter and balance out the understeer a bit. I have Koni Yellows installed (about a year old now) and ran those at a full turn off of full soft front and rear during the race. I also noticed a fair amount of dive/squat that I'd like to mellow out.

My thoughts on options are:
Lowering springs - would likely do H&R as from what I can tell, they're the stiffest and provide a reasonable drop (wouldn't hurt to fix the ole' xdrive rake too)

Sway bar(s) - what would the right combo be here? Stiffer rear bar?

Bushings/control arms refresh, etc. ? My car has about 96k on it but I've had the suspension inspected recently and nothing was noted to be busted... though I'm sure new bushings would feel nice.

What will make the biggest improvement?

I just did refresh and upgrade on 328 xDrive E90.
1. I didn't lower vehicle as I ski once a week. Went Bilstein B6 dampers. Excellent!
2. Rear suspension:
-Monroe shock mounts (upper and lower). Uber cheap and really good upgrade.
-Powerflex street performance bushings. Excellent too. But knowing what I know now that they absolutely don't increase NVH, I would go race (black ones).
-TRW M3 control arms in the back. All other control arms including links and sway bar bushings are lamforder.
-Front you cannot go M3 due to bigger subframe on xDrive. I replaced with Lamforder parts.

3. I changed every single coolant hose and water pump.
4. Installed Euro intake and deleted resonator.

I didn't go on track yet with new suspension, but with this I could easily out-corner E90 with sport suspension. Also in photos upper wishbone is not correctly positioned. I fixed it.
If you are not using car in deep snow like I do, lower springs (H&R is good), and go larger sway bars. I know people do M3 sway bars. If you go larger you might want to go Powerflex sway bar bushings.
Also, you do autocross, you might want to go solid bushings in rear subframe. But bushings are A MUST!
Did you install any kind of oils cooler? I would at least install fluid/fluid box if not full retrofit from 335 (i did that).

[sav_e92]

Originally Posted by edycol

I just did refresh and upgrade on 328 xDrive E90.
1. I didn't lower vehicle as I ski once a week. Went Bilstein B6 dampers. Excellent!
2. Rear suspension:
-Monroe shock mounts (upper and lower). Uber cheap and really good upgrade.
-Powerflex street performance bushings. Excellent too. But knowing what I know now that they absolutely don't increase NVH, I would go race (black ones).
-TRW M3 control arms in the back. All other control arms including links and sway bar bushings are lamforder.
-Front you cannot go M3 due to bigger subframe on xDrive. I replaced with Lamforder parts.

3. I changed every single coolant hose and water pump.
4. Installed Euro intake and deleted resonator.

I didn't go on track yet with new suspension, but with this I could easily out-corner E90 with sport suspension. Also in photos upper wishbone is not correctly positioned. I fixed it.
If you are not using car in deep snow like I do, lower springs (H&R is good), and go larger sway bars. I know people do M3 sway bars. If you go larger you might want to go Powerflex sway bar bushings.
Also, you do autocross, you might want to go solid bushings in rear subframe. But bushings are A MUST!
Did you install any kind of oils cooler? I would at least install fluid/fluid box if not full retrofit from 335 (i did that).

Thanks! I do already have monroe rear shock mounts and also whiteline subframe bushing inserts. I'll think about the M3 rear end components as well. I live in Vermont where we have plenty of snow but roads are typically plowed well enough that I wouldnt be driving through anything deep. I dont have an oil cooler, I'm not sure my engine will stay hot long enough during autocross to need one but will explore if the time comes.

[edycol]

Originally Posted by SAVAGE_VT_E92

Thanks! I do already have monroe rear shock mounts and also whiteline subframe bushing inserts. I'll think about the M3 rear end components as well. I live in Vermont where we have plenty of snow but roads are typically plowed well enough that I wouldnt be driving through anything deep. I dont have an oil cooler, I'm not sure my engine will stay hot long enough during autocross to need one but will explore if the time comes.

So IMO inserts are not enough. For autocross you really want as solid as possible.
I would install fluid/fluid exchanger. Reason is not that autocross will put you in limp mode (track would probably depending on altitude/ambient temperature). But N52 dials back timing fairly quickly. You won't overheat but you might lose some time.
H&R is way to go for springs. Also they offer aftermarket thicker sway bars.

[sav_e92]

Originally Posted by edycol

So IMO inserts are not enough. For autocross you really want as solid as possible.
I would install fluid/fluid exchanger. Reason is not that autocross will put you in limp mode (track would probably depending on altitude/ambient temperature). But N52 dials back timing fairly quickly. You won't overheat but you might lose some time.
H&R is way to go for springs. Also they offer aftermarket thicker sway bars.

Thanks for the tips! Ordered H&R springs tonight and will hope to install them this upcoming weekend... Will let you know how they turn out!

[sav_e92]

Got the H&R sports installed today along with Dinan static camber plates and so far am very satisfied. The car is firmer and flatter, and so far without an alignment seems to hug the road a bit better. I have an alignment scheduled for Monday and an autocross day on Fri. so I'll get to put these through their paces then. I did notice that my front end bushings look very worn... not to the point of complete failure, but they seem pretty soft. That'll be next on the list for a few months down the road.