N55 E88 First Mods!

[tjswarbrick]

Recently acquired a '12 6MT M-sport DSM/Oyster 135i.
She's my DD. Though I'd love to try an autocross one day, and plan to do a HPDE course next year and squeeze in the occasional track day, it's not a race car, my wife will (occasionally) drive it, my kids will ride in it, I commute ~ 40 miles a day, and will take it on road trips about 250 miles each way every couple months - along with blasting the back roads and twisty bits of Northern California when I can break away from other responsibilities.

I've wanted Pilot Super Sports on a BMW since before which BMW I knew I was going to get. (Had S-04's on my C-Class before.)
Now I see they may overwhelm the chassis.

So:
There's still plenty of tread on the SP 01 RFT's, and I'm still getting a feel for the characteristics of the car - so I'm in no hurry.

I'm planning to go 225/40 F and 245/35 R.
I'm also planning to get the Whiteline RSFB's at the same time, whenever that is.

Coilovers are distant future for me - if basic mods are unsatisfactory, or when the original shocks wear out. I thought I was going to go KW SC's, but I don't see 'em for the 'vert. So will look into ST XTA or TC Kline, unless/until I hear SC's will work.

In the meantime, to get a little of the 1M handling magic (reduce terminal understeer for minimal cash outlay without compromising DD ride composure), I'm thinking of either tapered 26.5mm E90 335i or straight 26.5mm E92 M3 front sway bar; and pull the alignment pins and add M3 control arms to add a little negative camber. Do I need anything else to optimise control, response, grip and feel yet maintain BMW's legendary (and most prized) ride/handling balance?
Not looking to invest in M3 steering rack or square wheels just yet.
But if there's another small piece I'm missing, I'd love to know.

I do see that the M3 sway is popular around here. Anybody try the 335i bar?

Thanks!

- Tom

[swagon]

- Tires
- Subframe bushings
- Shocks (at minimum)

Thank me later.

For reducing understeer, you need more camber up front - easiest way IMHO is the alignment pin mod and TRW/M3 lower control arms. I'd leave the sway bar for later. Someone with more knowledge might chime in with better info, though.

P. S.: Not sure if a convertible is a good choice for tracking...

[tjswarbrick]

Ha! I'm sure convertible isn't the best for the track - though hundreds (thousands?) of Miata drivers may tell you otherwise. As I told my wife - it adds expense, complexity, and weight while removing structural rigidity. Why would I want that? But we need to sell the convertible (Mustang ) she's owned for 25 years and it was a stipulation for going BMW. So I'll live with it!
Not a day has gone by (yet) where I've driven the car but not dropped the top!

Just to clarify - I need more negative camber up front, right?

[dbronnik]

Originally Posted by tjswarbrick

Just to clarify - I need more negative camber up front, right?

Yes

I'd recommend getting solid (aluminum + delrin) subframe bushings instead of whiteline inserts (they do cost more, but the labor costs more than the part anyway) along with camber plates. Also FWIW, I still run a stock FSB and don't see myself getting a different one any time soon.

Hope to see your e88 at a future BMW CCA GGC autocross event!

[tjswarbrick]

Was planning on the whiteline bushings - not inserts. The price appears decent, I've read several positive and zero negative reviews. And rumor has it that they are 2-piece units and can be installed without dropping the muffler or subframe.


I've heard too many stories about clunking/clicking/obnoxious camber plates so I'm trying not to go there for the DD. hoping control arms and upper links will do it on the front end - once I pull the alignment pins.

[tjswarbrick]

I've been reading and thinking about this a lot lately, even though I still have plenty of tread left on my RFTs. So I probably won't act on it until spring or summer.

I've joined BMW CCA, and plan to attend their next Car Control Clinic in my area. But without a 5-point harness and/or full cage I am ineligible (in this car) for Autocross and HDPE
They weren't going to be a large portion of my driving time, but I was really looking forward to improving my skills and seeing what she can do out there.

With that in mind, the car will not be tracked.
But it still needs better response, control, grip, and damping with less impact harshness. And some more negative camber. I'm always up for paying a bit more to get a lot more, but when the law of diminishing returns kicks in I back off and get the bang-for-buck kit.

When the RFT's wear out, I'm still planning on 225/245 PSS's.
Much as I'd like the M3 bushings, I can't see opting for them when the whiteline full bushing kit (KDT917) is so much less and can be installed without dropping the subframe.

5-piece TRW M3 front control arm kit is in my future, as well as an M3 front sway bar.

What are the benefits / tradeoffs of getting Dinan camber plates vs punching out the alignment pins?

Knowing it won't be a track car, but wanting to get a moderate drop and to maximize (or, rather, optimize) both road handling and comfort, without breaking the bank, should I be seriously considering the TCK SA coilovers (and which springs) or Koni Yellows over Swifts? Or do I need to move up to TCK DA's? My local motorsports shop recommended TCK SA's front and DA's rear with 400/600 springs - but, to me, that sounds like a streetable track setup. Not that there's anything wrong with that. But HPA lists their Swift R-Spec springs at 201/502 F/R, which is quite a difference.

Can those of you who have tried any of the above give some additional insight?

[dbronnik]

Originally Posted by tjswarbrick

But without a 5-point harness and/or full cage I am ineligible (in this car) for Autocross...

You don't need anything special for autocross; you can drive your car in stock form.

Originally Posted by tjswarbrick

What are the benefits / tradeoffs of getting Dinan camber plates vs punching out the alignment pins?

You'll get more range of adjustment from the camber plates and it will be easier to adjust.

Originally Posted by tjswarbrick

Can those of you who have tried any of the above give some additional insight?

I don't think you can go wrong between TCK SA or Koni Yellows over Swifts for a street setup.

I run a kit from Ground Control (custom valved Koni's + 440/700 Eibach springs) and it's not at all too hard for the street. Remember that our convertibles have some extra weight compared to the coupes so they need some stiffer springs -- 201/502 sounds like it might be a bit soft but it's going to come down to your own personal preference.

[litebulb]

I thought there are no adjustments for the dinan plates?
Thanks

[dbronnik]

Originally Posted by litebulb

I thought there are no adjustments for the dinan plates?
Thanks

Oops you're right! I forgot the Dinan ones are fixed. The Dinan ones will still yield you greater amount of negative camber than pulling your adjustment pin will though.

[tjswarbrick]

Thanks for the tips, guys.
Yes, I was thinking Dinan plates because they're not adjustable and, in my mind, set-and-forget with much less chance of creaking, clunking, or coming out of adjustment down the road.

I was looking at the BMW CCA GGC Auto-X events and they said 'Vert's need a harness installed. I haven't checked outside of that. Looks like you have some experience with it, db - any suggestions where I might want to start?

[dbronnik]

Originally Posted by tjswarbrick

Thanks for the tips, guys.
Yes, I was thinking Dinan plates because they're not adjustable and, in my mind, set-and-forget with much less chance of creaking, clunking, or coming out of adjustment down the road.

I was looking at the BMW CCA GGC Auto-X events and they said 'Vert's need a harness installed. I haven't checked outside of that. Looks like you have some experience with it, db - any suggestions where I might want to start?

From GGC Autocross:

"All cars are welcome and unlike our driving schools, stock convertibles are accepted – roll cages are not required."

I'd say going to GGC car control clinic is a good place to start -- or you can just dive into an event. Feel free to shoot me a PM if you have any questions

[tjswarbrick]

Originally Posted by dbronnik

From GGC Autocross:

"All cars are welcome and unlike our driving schools, stock convertibles are accepted – roll cages are not required."

I'd say going to GGC car control clinic is a good place to start -- or you can just dive into an event. Feel free to shoot me a PM if you have any questions

Good to know!
I can't find the conflicting information on the site right now, and some folks on yesterday's Tour said basically the same thing as you.
So I'm going to go with that!
I'm keeping my eyes open for the first CCC of the new year, then I'll start looking at some Auto-X events and other possible track time.

[tjswarbrick]

I feel the time has come for me to perform a chassis mod.
I have a couple stipulations though:

Relatively inexpensive - couple hundred or so(to start),
Can be performed DIY alone or with help from a 10-year-old in an afternoon without special tools,
Does not require removal and replacement of a bunch of hard-to-access stuff which is going to be replaced soon enough but not yet.

A little background:
I've done the CDV-Delete, swapped out the M-Sport shift knob for a ZHP, got the aluminum ER CP, and installed a K&N air cleaner element.
I've optimized air pressure in the stock Dunlop run-flat tires and switched to the recommended Castrol full-synthetic engine oil.

I absolutely love the car but feel the chassis dynamics leave some room for improvement.

RFT's still have plenty of tread life, so I don't want to simply discard them.
When I replace 'em in a year or two with PSS I'm going to go coil-overs to take advantage of the enhanced grip - and while the suspension is out do the RSFB's, M3 front sway-bar and control arms, and Dinan camber plates. (In for a penny, in for a pound, right?) (I may install the suspension components before replacing the tires knowing that they can be adjusted to suit later. But I'm just not there yet.)

Brakes are solid right now, but when they need replacement I'm considering RedStuff pads.

So - what can I do now that'll improve feel, response and/or stability, and perhaps cosmetics - without being detrimental to any of them?

I want to go Camber Plates, but my understanding is that I'll need to remove the front struts to get 'em in there. In which case I'm waiting 'till the coil-overs swap.
If I have that wrong, let me know and I'll jump on it.

Otherwise, the options I am considering are set of 4 VRSF 12mm wheel spacers (with extended bolts) OR the E90 M3 Front Sway Bar.

Are they both manageable DIY projects? Which would you do first?
Or am I missing out on something else which is vital, inexpensive, and relatively easy?

[litebulb]

Pretty close to what I have on. I got a great deal on the front end M3 suspension bits which really tightened up the handling. The biggest noticeable change was the RSFB. I doubt I will ever track my cabrio so I probably will never go coilovers. Redstuff is a great choice, but if I was to do it again, I would stay with OEM blanks.

[tjswarbrick]

Was planning on VRSF spacers, but saw some good reviews of others, too. (Burger, RENN, Macht Schnell, Rogue, and H&R.)
Found the RENN's on sale for super deep discount.
Went "square" with 12mm all around, and longer bolts.

Pics and impressions to follow, once they come in and I get 'em on.

[litebulb]

I put 12 mm MS on the back before, by widening the track it looked aggressive. I also didn't mind the way it handled, basically I could slide into a turn and the car would slingshot straight with the RFT. Now there's no way the spacer would work with my 255 PSS in the rear. Also the extra grip over the RFT, I think would cause issues. If you decide to go +1 tires, the new beefier rubbers looks good, better than stock but not as good as with spacers.

[tjswarbrick]

I installed RENN 12mm spacers under the factory 261 wheels last night.
Some gorilla had torqued the lug bolts to over 120lb-ft. So removing them was fun.

Cleaned up back side of each rim and outer brake hat with wheel cleaner/brake dust remover, scotch brite, denatured alcohol, and a clean cloth.
Just a dab of anti-seize on the lip of the hub and the lip of the spacer.
Tightened until stop, took a drive around the block, then torqued down new, longer bolts to right around 90lb-ft.

This morning there are no squeaks, clunks or rattles. Looks good and feels solid.

Pics to follow when I get the car cleaned up.

I thought I wanted coilovers. Doing more reading, I'm leaning toward Koni Yellows and Switft Spec-R's.

Allowing for different spring rates, anybody care to comment on ride/handling balance difference between Yellows with Swifts and their favorite set of coilovers when set up for similar drop and spirited-street driving?

[tjswarbrick]

Originally Posted by litebulb

I put 12 mm MS on the back before, by widening the track it looked aggressive. I also didn't mind the way it handled, basically I could slide into a turn and the car would slingshot straight with the RFT. Now there's no way the spacer would work with my 255 PSS in the rear. Also the extra grip over the RFT, I think would cause issues. If you decide to go +1 tires, the new beefier rubbers looks good, better than stock but not as good as with spacers.

Aren't the 313's E90 wheels? Don't they have a way different offset than 261's?

[asbrr]

Originally Posted by tjswarbrick

I installed RENN 12mm spacers under the factory 261 wheels last night.
Some gorilla had torqued the lug bolts to over 120lb-ft. So removing them was fun.

Cleaned up back side of each rim and outer brake hat with wheel cleaner/brake dust remover, scotch brite, denatured alcohol, and a clean cloth.
Just a dab of anti-seize on the lip of the hub and the lip of the spacer.
Tightened until stop, took a drive around the block, then torqued down new, longer bolts to right around 90lb-ft.

This morning there are no squeaks, clunks or rattles. Looks good and feels solid.

Pics to follow when I get the car cleaned up.

I thought I wanted coilovers. Doing more reading, I'm leaning toward Koni Yellows and Switft Spec-R's.

Allowing for different spring rates, anybody care to comment on ride/handling balance difference between Yellows with Swifts and their favorite set of coilovers when set up for similar drop and spirited-street driving?

Would love to see pics of this setup (spacers) when you get a chance. I'm thinking of going the same way, adding some mild spacers and doing a spring/shock combo. Which combo is the big question, i'm leaning towards the white externally adjustable Konis from HPA, but not sure on spring as I don't want to lower too much. Thinking BMWP yellow springs, unless there is a similar aftermarket spring (in terms of lowering) that also works...

[litebulb]

Originally Posted by tjswarbrick

Aren't the 313's E90 wheels? Don't they have a way different offset than 261's?

BMWP made 313 style in 18" with 7.5JX18 ET47 (BMW Part No. 36117891050)
and 8.5JX18 ET52 (BMW Part No. 36117891051).

[tjswarbrick]

Originally Posted by litebulb

BMWP made 313 style in 18" with 7.5JX18 ET47 (BMW Part No. 36117891050)
and 8.5JX18 ET52 (BMW Part No. 36117891051).

Ah. Cool.

I'll post some pics in the coming weeks. Maybe next Friday if the weather holds.

[tjswarbrick]

Originally Posted by asbrr

Would love to see pics of this setup (spacers) when you get a chance. I'm thinking of going the same way, adding some mild spacers and doing a spring/shock combo. Which combo is the big question, i'm leaning towards the white externally adjustable Konis from HPA, but not sure on spring as I don't want to lower too much. Thinking BMWP yellow springs, unless there is a similar aftermarket spring (in terms of lowering) that also works...

Eibach Pro Kit says it lowers .8 & .5 inch on convertible, but 1.5 & 1" on Coupe. Not sure I understand. Plus they're progressive-rate.
Lots of posts pointing out the Dinan springs are really close to BMWP. But I don't see them for our cars on their site any longer.
RS-R has similar rates to BMWP, but about twice the drop.
Soooo many springs...