mad_hatter's STX 128i

[mad_hatter]

Hi Everyone!

I want to start a log for building and competing in my 128i prep'd for STX. I'm in Ontario, Canada outside of Toronto. I got bit by the autocross bug after I picked up a new MK7 GTI and deciding to give it a shot in 2018. That year I won the rookie trophy at the local club, and in 2019 I won the club championship using my GS prepped GTI. It was a pretty simple setup:
-Audi BBS wheels in stock sizing, with 245/40/17 RE71R front and 225/45/17 rear
-034Motorsports rear sway bar and end links

Last year was a bit of a waste, only did a pair of events but it gave me time to consider options. I knew I wanted to move into an ST class, and with something RWD. FRS/BRZ is the obvious choice, but it didn't speak to me. I stumbled across a few old threads here from STX guys, and started to look harder at the 128i as a platform. In the end, the entry price was appealing and I got the stamp of approval from my fiancee. It took some searching, but I found the slicktop/6spd combination I was looking for.

As purchased:
-187,000kms
-OFHG and valve cover recently done
-oil pan gasket is dripping
-BMS short shifter w/ M alcantara boot
-M Performance steering wheel
-3stg manifold and tune*
-silicone inlet elbow
-secondary cats deleted
-135i muffler (not sure if it's any different?)
-Android auto display on the dash
-M front tension rods and rear guide arms*
-Rear subframe bushings done
-M3 front sway bar
-stock sport pkg rear sway bar
-brakes done recently, unknown brands yet

Plans for this year:
-Fix the oil pan leak
-Make it STX legal*
-poly bushings everywhere
-Ohlins from 3DM
-BBS LMs 17x9

Plans for next year:
-limited slip diff, TBD
-headers
-tune

De-modding it
In order to be STX legal, there's a few things I have to undo:
-The 3stg intake manifold will need to be replaced with the stock piece. Fortunately the seller had the stock one and included it with the sale. Should I go get a BMW dealer to flash the stock tune back on?
-The M front tension arms are *I think* legal because they only add change the liquid filled bushing for a solid one. The length itself doesn't change. The M rear guide arms will need to be replaced with stock ones, since it has a metal bearing in one end.
-Not necessarily for STX, but the android auto screen is huge and right in my line of sight... So that's gotta go. I've ordered a pocket from a ROW-spec E82, and I'm hoping it will fit the cutout opening.

Thanks for reading, I'm looking forward to being a part of the community!

P.S I promise better photography and photos in the thread rather than attached in the future.

[asbrr]

Very cool - your car sounds similar to mine in a lot of ways (some of the mods, mileage, and even the oil pan sweat haha).

You'll be able to get some money for the parts you're removing at least. For the tune, the dealer is going to rape you likely. I'd take a look at Bimmerlabs, you should be able to flash back to OEM from them (they offer the OEM 330i tune for the 3 stage intake manifold so figure you can load the stock tune too?).

[lowside67]

The M front tension arms are legal since they are identical other than the bushing, which is permitted to be changed. One of the biggest performance increases in my car was having custom bushings made on the wishbone to add camber - similar to installing the M arm, but legal for STX. This got my car from around 2.8 degrees to 3.8 degrees camber and it got MUCH faster as a result of this additional camber.

The LSD I had installed, the DiffsOnline ramped unit, is expensive. However, this diff absolutely transformed the car and I would emphatically suggest finding the money for it rather than compromising for a cheaper unit. The 128's biggest advantage over the FRS is its torque and the ability to put it down, so maximizing this is a real priority in my opinion.

-Mark

[mad_hatter]

Originally Posted by asbrr

Very cool - your car sounds similar to mine in a lot of ways (some of the mods, mileage, and even the oil pan sweat haha).

You'll be able to get some money for the parts you're removing at least. For the tune, the dealer is going to rape you likely. I'd take a look at Bimmerlabs, you should be able to flash back to OEM from them (they offer the OEM 330i tune for the 3 stage intake manifold so figure you can load the stock tune too?).

I see you're in the GTA as well, hope to see you out at an event! I usually am at TLMC, but sometimes PITL and I'm going to try WOSCA this summer too.

Originally Posted by lowside67

The M front tension arms are legal since they are identical other than the bushing, which is permitted to be changed. One of the biggest performance increases in my car was having custom bushings made on the wishbone to add camber - similar to installing the M arm, but legal for STX. This got my car from around 2.8 degrees to 3.8 degrees camber and it got MUCH faster as a result of this additional camber.

The LSD I had installed, the DiffsOnline ramped unit, is expensive. However, this diff absolutely transformed the car and I would emphatically suggest finding the money for it rather than compromising for a cheaper unit. The 128's biggest advantage over the FRS is its torque and the ability to put it down, so maximizing this is a real priority in my opinion.

-Mark

Thanks for chiming in Mark! Your thread is one of the ones bookmarked for reference. Lucky enough, I found a set of custom offset LCA bushings - so I'm on the right track there. I did order a full set of whiteline bushings, so I might just replace the tension rod bushing with the whiteline poly since I own it.

Diffsonline vs Mfactory is where I'm at now with the LSD choices, I want a clutch-type and both offer custom ramping.

[lowside67]

IMO Diffsonline is the easy choice. I don't have any particular issue with Mfactory but at least 3 of us have had direct positive experience with the Diffsonline build for STX 128s and frankly Diffsonline is a frequent choice for top shelf, professional race builds where I don't think Mfactory has the same pedigree.

-Mark

[SKI-R]

Doh, you have a set of offset bushings already, disregard this blather, sorry.

Offset bushing option....https://www.1addicts.com/forums/show....php?t=1789500

I actually set up at -3.4 degrees camber using just plates (KMac), there’s a minor amount of additional available.

It’s a rabbit hole, as you’re aware - have fun!

[asbrr]

Originally Posted by mad_hatter

I see you're in the GTA as well, hope to see you out at an event! I usually am at TLMC, but sometimes PITL and I'm going to try WOSCA this summer too.

Interesting, I used to do some PITL way back in the day (like 15+ yrs ago lol), and did a couple of TLMC track days around then too...I might pop into an event or two with my other car sometime this summer, maybe will see you around!

[mad_hatter]

Well I got my basement work shop cleaned up, and took apart the BBS LMs. Sending them out for machine work that will take 4-6 weeks... so gotta get on that. In the meantime, I can clean the barrels properly and polish the lips & hardware (as well as start checking off the rest of the items on the list).

I turned four of these:


Into this:


And since I was there, why not mock one up with the reverse mounted face (left) to get a preview of what it will look like? Compared to the standard front-mounted face on the right:


Flickr Album https://flic.kr/s/aHsmUBUgtX

[mad_hatter]

It's been chilly around here still, and although I've got bushings in hand - honestly I didn't want to be laying on cold concrete in the garage! So I decided to take on removing the Android screen the P.O. installed. Credit to them, they did a clean install, but that meant to uninstall it I had most of the dash apart, the trunk, the backseat, the door sill, and the centre console All in, I was about 9 hours over 2 days.

While everything was out, I took advantage and cleaned it all. I used Qtips, small brushes, and a bunch of cloths to get rid of years of debris and grime. There was a drink spill in there at some point and it was in everything, so I'm happy I took the time.

I also adjusted the short shifter that had come loose (it has a height adjustment on it that backed off), to a better height for me. And now it's tight so the gear lever feel is much improved.

Sorry about the potato-cam photos, the garage isn't well lit so I just used my phone. I'm just waiting on Amazon to bring me some u-nuts and I can finish putting it together and I'll pull the car outside for some completed pics.

[Mach3M3]

I just wanted to chime in here and say that another option for LSD is Jim Blanton at Performance Gear. He built an LSD for me and was extremely informative and responsive to my questions.

Most aftermarket clutch LSDs use the same 88 mm ZF clutch discs in different quantities (3 clutch, 5 clutch, etc) and in a variety of ramp angles and pre-loads. Jim can build a diff with these clutches no problem, thats what he did for me with 5 clutches, 30/90 ramps and 60 lb ft of pre-load.

[SKI-R]

Sport seats or race seats coming?

[mad_hatter]

Originally Posted by Mach3M3

I just wanted to chime in here and say that another option for LSD is Jim Blanton at Performance Gear. He built an LSD for me and was extremely informative and responsive to my questions.

Most aftermarket clutch LSDs use the same 88 mm ZF clutch discs in different quantities (3 clutch, 5 clutch, etc) and in a variety of ramp angles and pre-loads. Jim can build a diff with these clutches no problem, thats what he did for me with 5 clutches, 30/90 ramps and 60 lb ft of pre-load.

Thanks for the feedback! I'll add him to my list of people to contact about the diff!

Originally Posted by SKI-R

Sport seats or race seats coming?

It's on the list, but I'm not sure if it's in the budget for this year... I'm keeping my eyes peeled though, if the right deal comes up.

Ideally buckets (to save weight), and ideally a matching pair.

[mad_hatter]

Update time! I finally made time this weekend to get at the car, getting it ready for the first event this Saturday, June 19th. No pics yet, but here's the list

-BBS LMs are fully assembled, tires mounted. I'm happy to report that they're all straight and took 1oz or less to balance.
-Ohlins kit is in, currently set at the recommended heights by Ohlins and Barry at 3DM for a starting point. He did some custom damping for me, and I'll get the shock dynos to post for discussion later. No driving impressions yet.
-Rear guide rods changed out for aftermarket OE-style arms (for STX legality)
-Front LCA offset bushings installed into new OE-style arms
-Motorsport hardware wheel stud kit installed
-Changed back to factory IM from the 3-stage that came on the car

About the intake manifold. I found 2-3oz of oil in the manifold when I took it off, and I'm thinking the PCV/CCV must be faulty. Unfortunately, it's plastic welded to the valve cover So I need to either replace the valve cover or try one of the CCV kits and chip away at my existing VC to remove it and change it.

And as a question: I've read about people running the 3stage tune on the factory manifold - which is the situation I'm in now. Should I be concerned about that, or do I need to hustle and get the factory tune back into the ECU?

[mad_hatter]

Here's a pic of the refinished BBS LM's before mounting and on the car. More to come, and results from my 1st autocross event (from June 19th)!

Assembled! by Alex Torrance, on Flickr

Thread link:
https://www.1addicts.com/forums/show...0#post27736230

[StevieJ2]

They definitely look better now!

[mad_hatter]

June 19th
I missed the first club event of the season, due to a funeral. So this was the second club event of the year. I completely forgot to video anything.

First impressions:
Wow - I need to learn to drive differently. I cant just go in deep, rotate the car, and mash the gas like I could with the GTI. Driving the 1er will need to be finessed to be fast.

At the end of it all, I was 4th in ST classes and 8th overall. The field was small but most of the heavy hitters in the region were in attendance

July 10th
After having the experience of the first event, I was ready to start making some small setup changes to the car.
1) I ran slightly stiffer damper settings
2) I made note to work on tire pressures. I had run the previous event at 32PSI all around, and struggled with grip. Partly I assumed was just overdriving the car, but headed into the event I wanted to get a better feel. I ended up finding 28PSI the tires seemed to be happy and gave much improved grip.

This event was a same-day-double-header, where you run different courses for the morning and afternoon and add your best time from each to have the final result.

Morning:
I liked this longer flowier setup much better, and although in some early runs I made a couple errors (1 cone, and 1 massive understeer moment) on the final run I put together a run good enough for the lead in ST and 4th overall! Very promising indeed.

Afternoon:

This was a great course, I really enjoyed the short run because it made for a really intense 30 seconds. Unfortunately I couldn't post a fast time, you can see the transition around a hairpin at the 0:17 mark where I really struggled. I lost maybe 5 tenths there and it killed my momentum, and unfortunately I missed the podium.

Result:
4th in ST and 7th overall

I've got lessons to take away, and another event this weekend!

[mad_hatter]

Well I guess I should do a long overdue update. I'll have videos at some point before Christmas, but I've attached my season results. I'm extremely happy with my first season in the car!

It does leave me with a few things I'd like to do during the off-season:
1) LSD. definitely a requirement to make the car more predictable
2) Finally do the poly bushings in all the arms
3) New shifter, with reverse lockout. I really struggled with the 3rd --> 2nd downshift, I kept hitting the reverse gate and getting blocked.
4) Header/exhaust (if budget allows)

More photos to come, but the quality is all kinda shite - sorry.

[xrockoutx]

I have no constructive feedback, but those LM's go hard. Keep up the good work. 17>18