[simontibbett]

Introduction


Hi all, my name is Simon, and I am a racing addict. I wanted to share with you all my build which is an E90 BMW (325I) that we are preparing for club racing here in the U.S.

Before I begin, I wanted to briefly go over my resume. My racing background stretches back to karts, autocross, track days, and then club racing. I ran SCCA in numerous classes including T4, H Production, ITA, T3, IT7, and probably a few others. My biggest break came when I began racing in the FIA sanctioned 24H Series in a BMW M240I Racing Cup car before moving into GT4 in the 24H Series where we started the season finishing second in the Dubai 24 Hours on the final lap, which motivated us to chase the championship. We won the international title (in a BMW M4 GT4) which was a lot of fun. Lately, I have been racing at the Nürburgring Nordschleife in the NLS Series (formally VLN) once again in a BMW. I am also racing with the same team out of Germany that I began racing with in the 24H Series.







The plan for the E90 is to race endurance races with the World Racing League where I have raced many times before for another team. While I’ll still be racing overseas and other pro-am type events, the WRL series and other smaller endurance races offer me the chance to get seat time and have fun. It would be really cool to get some of my European teammates over here eventually to possibly do a race together on my side of the ocean. I’ll also be doing other club races with the car. All in the name of seat time.

The car:





I bought the car for $1,600 (6 speed manual) with a clean title. The car was a younger girl’s daily, but it had some issues, and her family just didn’t want to go down the BMW rabbit hole. The issue was simply an ELV malfunction (anti-theft steering lock system) and a very dead battery. Voltage issues and BMWs don’t get along. So, I plugged the laptop in, got juice, reset everything, and it fired up beautifully!

The goal here is to keep is very lightly modified in the engine department. Really just a better intake element and exhaust is what I am going for right now. We want to keep the car in the GP3 class where it could be a competitor. I’m also trying to stay on a strict budget.

Starting out, we did what we do best, rip stuff out:







We have the safety gear on hand and ready to go in thanks to RaceQuip. We will be using their FIA seat and FIA harness. This is the best bang for your buck FIA rated seat on the market. I refused to go with anything without a halo (the head protection) and this stole the show. We are also using their window net, right side net, and tow straps.

We also will be installing a Lifeline fire system which I recommend for any car that sees a race track. It’s far more effective than a handheld unit and most series require a real system these days. It’s a cheap price to pay for a peace of mind.

The first goal is to get the car track worthy to start developing it by running it on track. The E90 platform is of course a widely used race car especially in Europe so information is plentiful but since the purpose of this build is seat time, then what better way to develop it than being at the track.

Stages of the Build:

Stage 1: Gutting and preparing
Stage 2: Safety equipment (minus roll cage)
Stage 3: Suspension and Engine
Stage 4: Roll cage
Stage 5: Event Prep

[Brian86]

WooHoo

An early 325 will be an outstanding enduro car.

the e9x series doesn't get much love in US club racing. Drivers are hanging on the the old e36/e46, or skip forward to get the better turbo engines. The e9x just doesn't seem quite fit competitively in BMW club, NASA, or SCCA classes.

Good luck and have fun

[simontibbett]

Originally Posted by Brian86

WooHoo

An early 325 will be an outstanding enduro car.

the e9x series doesn't get much love in US club racing. Drivers are hanging on the the old e36/e46, or skip forward to get the better turbo engines. The e9x just doesn't seem quite fit competitively in BMW club, NASA, or SCCA classes.

Good luck and have fun

Yeah they aren’t super common for reasons you stated. There is a Spec E9X in the works for NASA there’s some cars running and being built. Then in SCCA I looked in the GCR but it’s not really listed anywhere competitive. As you said, for some of the classes with newer machinery going with the turbo engines seems popular in classes like ST.

I look forward to playing with it in the enduro stuff and dipping into some sprints for seat time wherever it falls into.

[Brian86]

WRC is no joke. A lot of big budget cars showing up in stacker trailers. It'll be an uphill climb. Of course putting together 4 pro drivers is going to make a big difference compared to gentleman and amateurs.

Club enduro racing seems to be moving into a new golden era, between lemons, champ, SCCA, and WRC... no shortage of races to attend.

Been doing TT's for ages, but I really need to get into a crap can enduro this summer.

[simontibbett]

Originally Posted by Brian86

WRC is no joke. A lot of big budget cars showing up in stacker trailers. It'll be an uphill climb. Of course putting together 4 pro drivers is going to make a big difference compared to gentleman and amateurs.

Club enduro racing seems to be moving into a new golden era, between lemons, champ, SCCA, and WRC... no shortage of races to attend.

Been doing TT's for ages, but I really need to get into a crap can enduro this summer.

I assume you meant WRL. Yeah for sure it’s grown from a step up from Chump Car to poor man’s IMSA now. We ran in it from 2016 or 17-2019. It has come a long way! We’ll be the smaller grassroots team for sure.

[Fiasco]

Nice! Looks like a great build underway, and a really great backstory to go along with it. How did you manage to get on racing for Sorg Rennsport?

[simontibbett]

Originally Posted by Fiasco

Nice! Looks like a great build underway, and a really great backstory to go along with it. How did you manage to get on racing for Sorg Rennsport?

I was committed to doing the inaugural COTA 24H back in 2017 because I had always been a huge fan of the 24H Series and seeing them come to the U.S. I was totally in. So I was looking for a team, and secured some sponsor funding. Their track record in Europe was good for me and I had always been a BMW fan. That really started it all!

[simontibbett]

UPDATE

So we've gotten into some more work now on the car. I installed the rain light that is required, we did a test fit of the seat, started routing wiring for our switch panel, and also started the suspension work.

For the seat I originally had gone with a Planted base and Recaro double-locking sliders since it's an endurance car. However, I could not get the seat to fit right with the sliders with this base as the tabs for I assume seatbelts were in the way.





I was able to get it mounted to the Planted base with just side mounts but since I need sliders I ordered a base from Bimmerworld. I'll get pics of that when I get to work installing it.

The seat installed via side mounts without sliders:





As I said it is an FIA rated seat from our partner RaceQuip. I was insistent we go with an FIA seat but also one with the halo. This seat is comfortable and very comparable to other entry-mid range halo FIA rated seats on the market.

Pro tip: when you have a one-year-old kid and need to work on the car outside during nap time:



Anyway, onto some wiring stuff which is still very much being done. The rain light is done which is simple and I just ran a cable from the deck lid where it is mounted, to a switch on my radio delete panel. It's getting power from a fuse jumper which I would normally hesitate using but for something like this and something not always used I don't see any problems.

The car had some aftermarket radio gear when I got it, I found this when getting into some of the harness...nice!



Holes drilled on the trunk for the light, there's just two wires off of it that go through my grommet there.



Here is what I decided on for a switch panel. It's really aluminum I just had some carbon fiber vinyl laying around and thought it looked nicer. It will have the main power button, rain light, driving lights, and the fire system pull cable if I can ensure it's mounted strong enough to not risk ripping out in an emergency.



So for suspension we will be using Bilstein coilovers. We also went with E9X M3 front control arms.





Unfortunately, Bilstein is having supply delays so we are testing with another brand's coilovers for the time being. However, we hope to have the Bilstein on for our first race in June.

Brakes are just blank rotors and for now, we are running Hawk DT60 pads. However, we are going to test some different options. In my experience, Hawk is typically pretty hard on rotors. We also have gotten steel lines from Bimmerworld.

So that's all for now, I need more pics. We hope to test the car next week at Road Atlanta and our first race will be at Daytona with WRL in June. Tire wise we decided to go with Hankook, they have a WRL team deal.

More soon and more technical pics as we dig in deeper!

[Brian86]

Brake pads should be easy to find. I never got around to X-referencing part numbers... but my e36 M3 looks to use the same pads as the little brakes on an e91 325.

Noticed the climate HMI is still in there. Would definitely go out of my way to keep basic HVAC in the car even if it's just an on/off switch for the blower & water valve(s) with the box vents zip-tied permanently to the glass. Heater cores are a failure point, but heat to defrost the windshield is a godsend.

[simontibbett]

Originally Posted by Brian86

Brake pads should be easy to find. I never got around to X-referencing part numbers... but my e36 M3 looks to use the same pads as the little brakes on an e91 325.

Noticed the climate HMI is still in there. Would definitely go out of my way to keep basic HVAC in the car even if it's just an on/off switch for the blower & water valve(s) with the box vents zip-tied permanently to the glass. Heater cores are a failure point, but heat to defrost the windshield is a godsend.

Yeah I’m wanting to keep the blower fan and defrost for sure. Been in cars without it and it can get interesting. Lol Glad to know the heater core can be a weak point though, I’ll have to put that into consideration for sure.

There’s tons of options out there for pads. I was going to go with Pagid first but they’re more expensive. I plan on running both on a test day to see which feel better.

[Brian86]

I meant the heater core is a weak point in a race car in general, more cooling lines, more gaskets, more plastic... e90's are no worse and no better than any other BMW AFAIK. My daily has 16 years and 360k on the original.

I'm a carbotech guy for brake pads, but there is a lot of great stuff out there.

Benefit of carbotechs for enduro is they are very gentle on the rotors. There won't be any problem running a single set of rotors for 12+h, which is one less thing to think about changing on the fly.

Every pair of rotors I consume get scrapped for TMF cracking doing TT, never for thickness. Enduro one would be moderating brake use to limit fatigue, and the rotors would probably go 24h.

[simontibbett]

Originally Posted by Brian86

I meant the heater core is a weak point in a race car in general, more cooling lines, more gaskets, more plastic... e90's are no worse and no better than any other BMW AFAIK. My daily has 16 years and 360k on the original.

I'm a carbotech guy for brake pads, but there is a lot of great stuff out there.

Benefit of carbotechs for enduro is they are very gentle on the rotors. There won't be any problem running a single set of rotors for 12+h, which is one less thing to think about changing on the fly.

Every pair of rotors I consume get scrapped for TMF cracking doing TT, never for thickness. Enduro one would be moderating brake use to limit fatigue, and the rotors would probably go 24h.

Oh gotcha!

Yeah I’m expecting to have to change pads in a 14 hour we are doing. When we use to run an NC MX-5 Cup car in that race it would be metal on metal by the end with similar pads and less weight. We’ll see though. No matter which set we go with I’ll have a set of bedded in rotors/pads ready to swap over. Ideally though as you say if we find something that lasts then it’s less to think about. Or remind my teammates we don’t need to be destroying the brake pedal in every brake zone. Lol

[Brian86]

Didn't mean to give the impression carbotech *pads* will last the full race I really don't know. They make an RP2 pad for euduro, but I don't have any experience on them. The XP series I'm familiar with most certainly will not.

But the rotors will be good.

That's a phone call to the tech team to find out.

[Bufalo]

RE: Brakes - Are you staying with 328 sized rotors and calipers, or increasing to 335 hardware?

[simontibbett]

Originally Posted by Bufalo

RE: Brakes - Are you staying with 328 sized rotors and calipers, or increasing to 335 hardware?

Right now just keeping the stock size with no upgrade. Still plenty of options on the market for pads.

[Brian86]

Since they fit over the little 325 brakes... I'd run 16" wheels as well. Should be a little easier on the wallet and a little extra compliance in the sidewall will suit endurance style driving.

Wheel and tire packages will be very inexpensive if you're sticking with OE wheels running 205 or 225. I'm partial to the #156s, which can be had for $40/ea all day long at salvage yards.

[simontibbett]

UPDATE

OK, so we finally got the E90 out for some testing at Road Atlanta a few weeks ago. This was just a Chin track day so no racing. To get ready I still needed to finish up installing our RaceQuip seat and belts along with a roll bar. I have a full cage from Kirk Racing which is a pre-fab but I am not using it, just this rear half for these track days until we can have a window to get the car into a fab shop. It’s obviously been a huge delay in the build.





One thing I also said I was going to do was to install the BimmerWorld floor seat mounts which I did. They are so nice, loads of mounting options, threaded, it makes my life so much easier. For this event I just mounted the seat directly to this with the side brackets but for endurance races we will use the Recaro double locking sliders I have. Luckily my co-driver and I are similar build and height so this worked for the weekend.



Once that was all done, we put the other wheels on with new Hankooks and hit the alignment rack. We went with a very conservative setup, didn’t mess with rear toe, just the front which is out just slightly. The camber is very much on the conservative side as well.



Then it was off to the track!




I took the car out for the first warmup session to make sure nothing was falling off as I was sharing the car. After some cutting and adjusting the undertray panels we were good.

I decided to just run a handful of laps to see what we had. I accidentally forgot to turn the traction and stability control all the way off so kept it short and easy to avoid cooking the brakes. The car out of the box was quite surprisingly good. We had the shocks all set in the middle and tire pressures were square to start. Weird I know but I like a good base to start at then adjust from there. Handling the car was loose in the high-speed stuff on entry but would develop a little mid-corner understeer. This quite possibly could have been the DTC but also like I said it was a totally neutral set setup. Either way it was doing quite well. I did a high 1:49 I think or low 1:50 after a couple of laps. There’s an easy two seconds at LEAST from turning DTC off and then quite a bit with setup work.

Engine wise it is bone stock. It runs strong, it’s of course slow, and the gearing is TERRIBLE. Which I kind of expected as we are still using the stock 325I diff, I have read the auto one is what you want for better gearing. Then we’ll add an LSD.



When my co-driver got in he had a 30-minute session, I told him to take it easy and just feel the car out. He was looking good and stayed out for almost the entire session which surprised me! Unfortunately, as the checkered flag came out, so did his call that the car was stuck on the side of the track, there was smoke, and that’s about all I got.

It turned out the right front caliper seemed to have seized. I am not sure why. Either the brakes got way too hot or there was a faulty part in there. Anyway, it managed to light a small fire which was enough to burn the new bushings there as well as the wheel speed sensor wiring. It also burnt the inside of the wheel pretty good and destroyed the tire. The body is fine. He told me the pedal started feeling soft so he backed down for a few laps but then it was too late.

Looking at the tire it was obviously locked up massively for a moment to do that much damage!



Needless to say, our weekend was over. So, the next plan is of course to replace the damaged items. Then we will take it back out for a track day to do a little more testing before we race it.

I am quite busy in August and in September I’ll be in Germany the entire month racing three back-to-back weekends at the Nordschleife! I’ll post some pictures and updates from that. By the way if anyone is interested in running there, hit me up! I can help every step or even help ship your own car there and store it by the circuit.

[blnk-128]

Quite the eventful test session! I'm following along as I continue to develop my 128i for the track. Appreciate the large updates, keep em comin' and good luck across the pond.

[mattanderson]

Are 335i brakes an option? Cheap + easy bolt-on.

Have you coded out the nannies? One of them applies extra braking pressure when it thinks the brakes are fading. There are a few others you'll want to code out, as well.

[Tambohamilton]

Originally Posted by mattanderson

Are 335i brakes an option? Cheap + easy bolt-on.

Have you coded out the nannies? One of them applies extra braking pressure when it thinks the brakes are fading. There are a few others you'll want to code out, as well.

Yes. Ready alert braking, engine power reduction, the emergency stop one (forget what it's called - maximum braking support?), and others. You may even want to code out the e-diff already, since you'll have sticky tyres and not heaps of power.

[Brian86]

I've never seen that level of carnage on RS-4. That tire wears like iron, I don't think there is any possible way that was done by wheel lock under braking. Did it get flat-towed in with the wheel locked?

Big brakes are nice.... but not really necessary for a club/amateur enduro car. It's awfully difficult to make it 6 or 10 or 14 or whatever hours if the car is being driven so hard bigger brakes are necessary.

And they come with the major disadvantage of larger wheels.

16" wheels fit tires that are much cheaper, and 16" tires have more sidewall which is significantly more forgiving on the mechanical suspension and driveline bits. Particularly true on the southern tracks that tend to use some rather harsh scallops and gators to deter drivers from using them too much.

[Brian86]

Speaking of tires, give the Conti EC-F a try if it's an option.

At least as fast as the RS-4, I think perhaps a smidgen more. They have a REALLY big offset at the bead so for the same size tire on the same wheel the EC-F is easier on the outside shoulder, tending to wear the entire contact patch more evenly.

But they are 20% more expensive than the Hankook.

Don't get enough seat time in the rain to be a fair judge of wet performance between tires.