Track Build (Weight Reduction, HPDE)

[spxxx]

I figured that I would start a build thread, I never thought I would do this but as I get more into the build I figure people could learn a thing or two from my experiences/mistakes.

The car was purchased from a older fellow who bought it new in 2008, this car was the test bed for Dinan E82 parts. When I picked up the car it had full Dinan "Stage 3" parts (Koni struts, Dinan Springs, Dinan FMIC, Dinan Oil Cooler, Dinan Stage 3 tune, Dinan Sways, etc) but this was obviously not enough... lol

Just checked and I did my first track day in Q3 2015, so it's been about 2.5yrs. It all started very modest as I was saving for a house and my startup was still growing aka I didn't have the money to track, in Q3 2017 I started getting serious with the car knowing that 2018 I would start competing in Time Attack/Trials and try to be competitive.

Once the real fun started, I started getting aggressive quickly... I swapped over some parts from my E92 335i I had previously and have slowly been building since.

N54 Engine:
- MHD 25% E85 Tune
- BMS DCI
- Dinan FMIC
- Dinan Oil Cooler + Setrab 34 row In-Line (being installed asap)
- Custom AT Cooler
- VTT Silicone Inlets
- VRSF DPs
- BMS Chargepipe

Suspension:
- MCS 1WNR (KW V3 + ST XTA + Bilstein PSS9 + Koni Previously)
- GC Camber Plates + Notched Tower
- Dinan F/R Sway Bars
Front:
- Hyperco Springs #400 Springs
- Megan Front Strut Bar
- M3 Front Control Arms (Upper/Lower)
- Rogue Engineering Front Control Arm Monoball Bushings
Rear
- Mfactory LSD (Helical)
- Swift #672 Springs
- Powerflex Subframe Bushing inserts (Front position) **Need solid ones ASAP
- Powerflex Black Subframe Bushings (Rear Position)
- Rogue Engineering Rear Toe Arms
- SPL Rear Camber Arms

Brakes/Tires/Wheels:
- Stoptech ST60 BBK (Front)
- Stock Rear
- RE71R 275/35 Square
- Apex EC7 9.5x18 Square

Interior/Exterior:
- OEM 1M Front End
- Sparco Sprint Seats
- Schroth Quick-Fit Harness
- Custom 4 Point Half-Cage
- Custom Mounts & APR Rep Wing

Weight Savings:
- Rear Seat Delete (-55lbs)
- Bimarco Seats (-65lbs)
- Various Underhood Pieces (-10lbs)
- Apex Rims (-33lbs)
- Battery Swap (-24lbs)

Future Mods:
- Full Exhaust (-60lbs)
- Gutting Weight to shoot for #2950... unlikely
- Other Aero?
- 1M rear


Recent (I'll have some on track pics ASAP)



I'll add more pics soon!
Only "stock" photo I have of the car:


More Recent:




Goals:

[JCip91]

I love the progression of the build. Our cars look pretty similar haha How did you do your transmission cooler? I am looking to build one but I have no idea on where to start.

[houtan]

Looking forward to updates.

Any pictures of your seats? How you installed them? Can you get them a lot lower than the OEM seats?

[WhatsADSM]

Wow that's quite the list. Should be pretty nice on track.

Do you have specs for the 700# rear springs? I am thinking of doing that as well with my XTA kit.

Also why did you change to 400# swift springs up front? Linear 400s should come with the XTA out of the box?!

[spxxx]

Originally Posted by WhatsADSM

Wow that's quite the list. Should be pretty nice on track.

Do you have specs for the 700# rear springs? I am thinking of doing that as well with my XTA kit.

Also why did you change to 400# swift springs up front? Linear 400s should come with the XTA out of the box?!

I misspoke actually, I just took out the front helper springs to fit really wide 255 tires up front (closer to 265). I'm running 9 inch swift #672 springs in rear which are tested to be closer to #705.

Trying to get to 1:45ish at Laguna and ~2min at Thunderhill. The car is plenty fast, just need more seat time, this is only my 2nd season tracking.

[The Wind Breezes]

Look into a composite hood and fenders if you come across them for a good price. That stuff weighs a lot and you don't need any more weight up front. Also I know of a battery solution that will allow you to remove the heavy cables going to the rear and use a 6lb battery up front to start and power the car.

You also could lose the sunroof, it's pretty heavy and in the worst place possible. You might also look into swapping the doors with a removable bar setup for the track days, the doors are unbelievably heavy.

Also if your trackday organization allows it you can run an open downpipe. It's not that loud due to your turbos acting as mufflers and you save a ton of weight without the expense of a full system.

[spxxx]

Originally Posted by The Wind Breezes

Look into a composite hood and fenders if you come across them for a good price. That stuff weighs a lot and you don't need any more weight up front. Also I know of a battery solution that will allow you to remove the heavy cables going to the rear and use a 6lb battery up front to start and power the car.

You also could lose the sunroof, it's pretty heavy and in the worst place possible. You might also look into swapping the doors with a removable bar setup for the track days, the doors are unbelievably heavy.

Yeah there aren't a lot of options for the sunroof delete. I would love a composite 1M front end to run 275 square tires My current 25lbs battery was $48 at Walmart haha I'll probably go with a Deka battery around 350cca as the car is still used for occasional weekend cruises.

[spxxx]

Does anyone still make a bolt-in cage for 1ers? I heard most companies stopped making them

[WhatsADSM]

Originally Posted by spxxx

I misspoke actually, I just took out the front helper springs to fit really wide 255 tires up front (closer to 265). I'm running 9 inch swift #672 springs in rear which are tested to be closer to #705.

Trying to get to 1:45ish at Laguna and ~2min at Thunderhill. The car is plenty fast, just need more seat time, this is only my 2nd season tracking.

Ahh ok. So its stock 400s with the helper spring removed (I did the same thing BTW), and then swift 672 rears. Makes sense.

Do you know the dimensions you used for the rear? I ask because I will probabl swap mine out next year for something a bit stiffer as well. The balance is close to neutral now but still a *bit* to understeery. A bit of extra rear spring should help neutralize it a bit more. Swapping to swifts will also change it from lightly progressive to linear.

I do second the idea above to see if you can lighten up some of the front body panels, while simultaneously adding room for additional tire width. A little more tire, as well as less weight on the front axle should be quite noticeable on these cars.

Depending on your level of experience you may want to just spend more $$ on seat time for now though. That will likely improve your lap times the most (while also being the most fun! ). Once you are reasonably comfortable and smooth with the car and pushing those Federal RSRRs to their limit (i.e. you should be in an advanced group) then you will probably want to move up in tire a bit. As you said something like a RE71 or maybe an "entry level" R-comp (NT-01, etc.) would be a logical next step. After that aero and brakes will be the biggest bang for the buck you will see for lap times.

In a nutshell I personally would go:

More seat time --> Improved tires --> Improved brakes --> Aero.

Safety is safety and always important so that can trump anything if you feel more comfortable with/without it.
Truth be told stuff like full exhaust, further lightening, etc, all are great but fall much lower on the bang-for-the-buck-o-meter.

[spxxx]

Originally Posted by WhatsADSM

Ahh ok. So its stock 400s with the helper spring removed (I did the same thing BTW), and then swift 672 rears. Makes sense.

Do you know the dimensions you used for the rear? I ask because I will probabl swap mine out next year for something a bit stiffer as well. The balance is close to neutral now but still a *bit* to understeery. A bit of extra rear spring should help put neutralize it a bit. It also changes it from lightly progressive to linear.

I do second the idea above to see if you can lighten up some of the front body panels, while simultaneously adding room for additional tire width. A little more tire, as well as less weight on the front axle should be quite noticeable on these cars.

Depending on your level of experience you may want to just spend more $$ on seat time for now though. That will likely improve your lap times the most (while also being the most fun! ). Once you are reasonably comfortable and smooth with the car and pushing those Federal RSRRs to their limit then you will probably want to move up in tire a bit. As you said something like a RE71 or maybe an "entry level" R-comp (NT-01, etc.) would be a logical next step. After that aero, brakes will be the biggest bang for the buck you will see for lap times.

In a nutshell I personally would go:

More seat time --> Improved tires --> Improved brakes --> Aero.

Safety is safety and always important so that can trump anything if you feel more comfortable with/without it.
Truth be told stuff like full exhaust, further lightening, etc, all are great but fall much lower on the bang-for-the-buck-o-meter.

Yeah exhaust would be for weight loss. And this is actually my 3rd season looking back now - still trying to shoot for 10-12 more weekends this year.

Luckily I'm spoiled in CA with a ton of local tracks and I've stopped traveling for work thankfully so I can dedicate almost 2 weekends a month to seat time. (If the wife approves)

[WhatsADSM]

Originally Posted by spxxx

Yeah exhaust would be for weight loss. And this is actually my 3rd season looking back now - still trying to shoot for 10-12 more weekends this year.

Luckily I'm spoiled in CA with a ton of local tracks and I've stopped traveling for work thankfully so I can dedicate almost 2 weekends a month to seat time. (If the wife approves)

I really don't know your capability as a driver so don't take it as a dig or anything. Just a general comment that seat time is typically the number one improvement in lap times, while also being the most fun. Only you can gauge your level of talent really. I know in my case I've been tracking a few weekends a year for 10 years, feel at home in advanced, and if I'm being honest I STILL I feel the car is still more capable than I am. So that's why i say seat time first.

I do appreciate wanting to do mods though, we have all been there. IMHO do the stuff that gets you the most bang for the buck and doesn't stunt your ability to learn (better yet teaches you more). I love weight reduction as much as the next guy, but as an example lets take your setup and duplicate it. One guys spends a few grand taking out ~100 lbs in exhaust, sunroof, and fenders. While the other spends a few grand on R-Comps, bigger brakes, and aero. There will be no contest. The latter will run considerably faster, may end up even more street friendly as well (would just have silly wings on all the time ). So yea to me tires, brakes, and aero next. After that I would consider further weight reduction and high end dampers.

[spxxx]

Originally Posted by WhatsADSM

I really don't know your capability as a driver so don't take it as a dig or anything. Just a general comment that seat time is typically the number one improvement in lap times, while also being the most fun. Only you can gauge your level of talent really. I know in my case I've been tracking a few weekends a year for 10 years, feel at home in advanced, and if I'm being honest I STILL I feel the car is still more capable than I am. So that's why i say seat time first.

I do appreciate wanting to do mods though, we have all been there. IMHO do the stuff that gets you the most bang for the buck and doesn't stunt your ability to learn (better yet teaches you more). I love weight reduction as much as the next guy, but as an example lets take your setup and duplicate it. One guys spends a few grand taking out ~100 lbs in exhaust, sunroof, and fenders. While the other spends a few grand on R-Comps, bigger brakes, and aero. There will be no contest. The latter will run considerably faster, may end up even more street friendly as well (would just have silly wings on all the time ). So yea to me tires, brakes, and aero next. After that I would consider further weight reduction and high end dampers.

Yeah totally agree, I started out as a wrench-nut when I was younger and have always been into mechanical engineering but in the last 2-3yr I've stopped caring so much about absolute power and started focusing much more on road course driving/suspension geometry.

I just need excuses to wrench when things aren't broken and unfortunately that means buying mods. At this point, I think the car is setup well enough for me to run for ~1-2yrs without any changes besides RComps and aero.

[spxxx]

Originally Posted by houtan

Looking forward to updates.

Any pictures of your seats? How you installed them? Can you get them a lot lower than the OEM seats?

They arrive tomorrow actually... Will update with pics. I went with OEM slider mounts to the seats which TJ at OGRacing said would be at a similar height as floor mounts.

They're great over there at OG for safety parts, and they price match other vendors which is awesome

[houtan]

Originally Posted by spxxx

They arrive tomorrow actually... Will update with pics. I went with OEM slider mounts to the seats which TJ at OGRacing said would be at a similar height as floor mounts.

They're great over there at OG for safety parts, and they price match other vendors which is awesome

Awesome. Looking forward to the updates.

[spxxx]

Good day at Laguna, with this 65* weather I put down a 1:48 with street camber and no alignment since the new coils.

Loving the car, rotates a lot more though now with the Swift #700 springs + 100lbs of weight reduction in the rear.

[spxxx]

Will upload footage from Laguna tomorrow! Stoked to get these seats in, they seem to just barely fit my lanky 5'11-6ft frame. Can't imagine many people fitting in these.

[spxxx]

Test fitting as I wait for my BK brackets, not sure why they're not more popular, they allow you to retrofit your electric seats into any standard side mount seat using an E30 window switch (the electric motor is only ~3lbs) and the height difference is small.

I'm pretty tall so I'm going with floor mount driver side and electric passenger side for the wifey on the occasional weekend drives.

[ayao]

What kind of power is your car putting down?

[spxxx]

Originally Posted by ayao

What kind of power is your car putting down?

I tune it to around 17psi (inlets) and 11.5 degrees of timing on an E30 tune for cooling that runs extra rich. Id guess a little under 400whp for the track. Hard to make crazy power that's linear and easy to put down on stock snails but 400-450ish is plenty if you can get down close to 3,000lbs.

On the street I could probably put down closer to 475 with my mods but that kind of power is unnecessary when you're just looking to get seat time.

[Dr1]

Originally Posted by spxxx

Does anyone still make a bolt-in cage for 1ers? I heard most companies stopped making them

I couldn't find anyone after searching a couple years. I gave up and did this. Actually picked the car up yesterday.

[spxxx]

Originally Posted by Dr1

I couldn't find anyone after searching a couple years. I gave up and did this. Actually picked the car up yesterday.

Whoa that is pretty! Mind me asking what you paid?

How did you decide on mounting points?

[Dr1]

Originally Posted by spxxx

Whoa that is pretty! Mind me asking what you paid?

How did you decide on mounting points?

It was $2000 painted. The mount points and plate size/shape were determined by the builders, Wicked Performance Group, local to me in New Hampshire. I chose them over other local shops based on their extensive experience building race cages for rally/hill climb cars.