Track Day Chronicles - My Progression from E30 to S50 Swapped E36

[econti]

RS4s are so good. I feel like E36 track cars are a natural progression from E30s, being that they're still common enough to be folded into a wall and not feel *too* bad about ruining another one.

[CubbyChowder]

Wow that bad fitment on the radiator is pretty surprising to me. I always sort of considered CSF to be the higher end option- I've been using Mishimotos on two different cars with good success for what it's worth, though people tend to say Mishimoto is poor quality.

Same! I'm definitely happy with the quality of the welds and construction of it but yeah, fitment could be better out of the box. Oh well, that's all just part of buying aftermarket parts.

RS4s are so good. I feel like E36 track cars are a natural progression from E30s, being that they're still common enough to be folded into a wall and not feel *too* bad about ruining another one.

Yeah they are great. I ran R-S4's on my E30 too and was super happy with them, put 5 hard track days on them and they still had a ton of life left when I sold them recently.

Also, that was kind of my thought process on the transition to E36 too. They are still plentiful and cheap enough to where I don't feel as bad stripping and caging one and driving it on the limit. After putting all that work into my E30 the last 2 years (with much more to come), I was growing increasingly more nervous about sending it off track and crashing it as I gradually pushed the car harder. So yeah, really happy to make the switch and try out an E36 from here. Plus, more grip and a better suspension layout is a nice upgrade too.

[CubbyChowder]

Coolant hoses showed up today so I was able to get the car all back together! The new hoses fit the smaller radiator barbs much better, so I feel like I made all this fuss for nothing.

While I was in there, I deleted the throttle body heater system to eliminate some leak-prone coolant hoses. I replaced the hose fitting in the head with a 12x1.5mm thread 250F VDO temp sender for when I add a coolant temp gauge down the line:



Radiator mounted up:



Got everything buttoned up, filled and bled the coolant and took it on a test drive. Everything seems to be working fine minus the heater still blowing cool air. Think I need to bleed the system a bit more tomorrow, but besides that the car drove great and held operating temp just fine. Feels much faster than my E30:



First track day at Buttonwillow is 2 weeks away! Can't wait.

[moatilliatta]

Bad Tstat?

[CubbyChowder]

moatilliatta - nope, didn't realize the center vent above the radio has it's own separate cold to hot dial (which of course was set to cold) thus giving me cold air. Heater blows hot now. I don't want to admit how long it took me to realize that one haha.

Car is pretty much ready for it's first track day. I changed the spark plugs today for the hell of it, switched from the OEM Bosch to NGK BKR6EK. Will do an oil change beforehand too. Pulled the car out and snapped some better shots of it - I want to drive this thing so bad!

[Panici]

Nice shots, looks decent for a track rat!

[moatilliatta]

I think those switches get sticky too! haha

Step colder plug is a great for track cars, esp if doing a tune.

I'm really loving the Early body E36's. They look so tough!

They age better yet in Cali than out in the Midwest. I think why it looks so refreshing.

[CubbyChowder]

What's funny is it's honestly much more presentable as a street car than my E30 is, haha. But, the E30 will get paint this year sometime I hope! I want to get more experience with auto paint so I'm considering getting some Alpine White II single stage mixed up and spray the hood, nose panel, front and rear bumper and lower side skirt area. I think it could look good all color matched.

[Panici]

I think it could look good all color matched.

Absolutely will look good.
Heck even if the colourmatch isn't 100% it's still better then the black/white contrast IMO.

[moatilliatta]

I'm the outlier enjoying the grey rockers. Really enjoy seeing it on the new G42 chassis. Takes me back lusting at E34 M5's

[CubbyChowder]

We'll see! I keep going back and forth. I do like the grey contrast as well but I'm leaning towards color match.

[CubbyChowder]

Long winded update! The car survived it's first track day yesterday, but I almost backed out from going.

The two weeks leading up to the event were a bit of a whirlwind, at one point I was convinced I either had a blown head gasket or a crack in the head somewhere. After getting everything buttoned back up after that first round of work, I could not get the cooling system to behave properly. It seemed like I was either taking on extra pressure or chasing air stuck in the system. I tried many of the different tricks out there and could not seem to get it to bleed properly. Coolant would always drop super low in the tank overnight and fill back up as soon as I removed the cap.

After learning about how horribly buffered the stock E36 coolant temp gauge is, I stole the VDO gauge from my E30 and installed it in the E36, and found that the car was holding operating temp at 100c (212f) which was a little warm for my liking.

Combustion leak test with the blue fluid in the expansion tank - came out clean
Leak down test at operating temp and got 2% leak down in every cylinder - but could hear air escaping through neighboring spark plug holes and the throttle body in a couple spots, so not sure what to make of those results
Compression test on warm engine showed 180-190psi across the board - this was after the leak down so the engine wasn't quite operating temp but still warm.

Tore everything back down and replaced the thermostat with an 88c, bypassed the heater core (I could smell coolant when the heater was on so I suspected a small leak) and replaced the expansion tank cap. After that, the system appeared to be bled properly and held operating temp at ~93c on the temp gauge which is much better.

This gave me the green light to take it out to the track yesterday and I planned to take it pretty easy. The car held solid temp through the whole first session and brakes/suspension/grip felt good so I felt comfortable to start pushing the car more in the following sessions. Overall, it was feeling awesome and it exceeded my expectations, I'm loving it. The seats are horrible, I was getting thrown all over the place constantly readjusting but I 100% expected that, and will be one of the first things to get addressed from here. Clutch and shifter need tweaking as well.

I managed to squeeze out a new PB at Buttonwillow CW13 - ran a 2:05.7 which is a 2 second improvement over my E30. It was honestly a very sloppy lap though and there are several areas on track where I need improvement. That will come in time. But all said and done, I am super pleased with it's first track outing and I am really looking forward to developing the car and my driving experience further together.

Jeeze, that's a lot of words... How about a picture:

[Panici]

Tore everything back down and replaced the thermostat with an 88c, bypassed the heater core (I could smell coolant when the heater was on so I suspected a small leak) and replaced the expansion tank cap. After that, the system appeared to be bled properly and held operating temp at ~93c on the temp gauge which is much better.

Maybe you had enough of a leak at the heater core to prevent the system from pressurizing? Would explain your operating temp near 100c.

Glad the trackday was successful!
So the E36 is faster then the E30, interested to hear how would you compare the feeling of the chassis' at the limit.

[CubbyChowder]

Maybe you had enough of a leak at the heater core to prevent the system from pressurizing? Would explain your operating temp near 100c.

Glad the trackday was successful!
So the E36 is faster then the E30, interested to hear how would you compare the feeling of the chassis' at the limit.

I'm thinking either that or maybe the expansion tank cap was faulty and not pressurizing properly. It was one of those two that did the trick.

The E36 is definitely significantly faster than the E30. It felt better in pretty much every way honestly. Grip, steering, braking, power, etc. I think if I wasn't flying around in the stock seats the whole time and was nailing my heel toe downshifts better I could've been quite a bit quicker even. The clutch pedal has a ton of travel and engages immediately off the floor so I kept messing that up, couldn't get used to it. Might replace master/slave cylinders and see if that helps. I think it has a UUC lightweight flywheel which I assume is thinner than the OG flywheel so maybe that's why it's requiring so much pedal travel. Wonder if there's a bigger throwout bearing I could install to fix that? I'm going to run a chassis mounted shifter eventually as well.

But yeah, the car feels great. I can't wait to cage it and get proper seats/harnesses, I think I will feel much more confident to push the car harder after that.

[CubbyChowder]

Got a pretty massive and picture heavy update! The car has seen a lot of changes in the past 6 weeks. I only got to do one track day in this car in Febraury and then got busy with life. Next thing I know, the year is almost over and I was seriously itching to get back out on track and see some more of my plans for the car through. I sold off a bunch of parts and a few cars so I had some space and time to crank out some projects that I've been wanting to address. I registered for 3 track days to end the year off and to act as a motivator with a deadline to get the car done. Let's get right into it.

At some point way earlier this year, I pulled the Getrag 250 out of the car to swap into a 328i E36 so that I could rob it of it's ZF 5-speed. It cleaned up really nicely and I did the detent service on it and then sat on it until I could swap it in. So, that was my very first order of business in this new round of work - finally complete the ZF swap.




I also bought a new driveshaft with serviceable u-joints and forgot to take pics of it, but it's in there. Did all new clutch master/slave cylinder, single braided steel clutch hose, replaced all the shifter bushings and all that jazz while I was in there too.

Next was exhaust. In an effort to save some weight, I decided to piece together a 3" system. I already happened to have a 3" rear section that I randomly bought off a local E36 guy, and scored a Bimmerworld midpipe locally as well, so I just had to bridge the two and I decided to add a resonator. Old setup on the left, new setup on the right:



Also installed some shorty headers because I had them around and figured why not:



Got the new exhaust all fabbed up and sprayed with some header paint and then installed:





With all of that back together, I could finally get the engine back together again. I took the intake manifold off when I pulled the Getrag 250 (stupid starter without threaded holes) and knew I'd be converting to a Euro coolant expansion tank, AKA the late model E30 expansion tank so I figured it'd be easier to figure out hose routing with all of it off.

I whipped up a silly looking bracket and got the tank mounted:





The angle of it was kind of necessary in order to run the distribution block. Since it's an early E36 chassis, it was mounted right below the ECU compartment and there was barely any slack in the power wires to relocate it, so I had to make due with what I had and ended up with that placement. Not the cleanest solution but works just fine. Was able to run a stock E36 expansion tank hose and routed it behind the head along the firewall and directly into the back of the timing cover. My cooling system is way more simple/minimal now and much easier to bleed! I also built a block-off plate for the coolant port on the back of the head for the heater core but didn't take pics of that.

Alright! So, at this point the car is back together and running/driving again. I replaced a bunch of fuel lines and the fuel filter, did new AKG motor mounts, did new hoses/gaskets everywhere that I could, etc. Just got it all sorted and dialed.

Now comes the fun stuff, lots of fabricating and making sure this car will never drive on the street again






Gutted as much as I reasonably could and pulled a TON of weight out of the car. I weighed things as I pulled them out and totaled over 370lbs! I was really surprised by that. Of course some weight will go back in with the new seats, exhaust, cage, etc but it will still be significantly lighter all said and done.

Had a gaping hole where the heater core used to be, so I had to address that. Built a block-off panel out of some aluminum I had around, forgot to take installed pics but I ran some silicone to seal it off:




With deleting the whole sunroof cassette, I salvaged just the sunroof panel skin and built some mounts to hold it in place and then caulked that in:





The biggest takeaway from my first track day in this car in February was that I needed proper fixed back bucket seats. I was flying around all over the place in the stock seat and didn't feel comfortable with that obviously. I did a bunch of research and asking around and eventually landed on these Bimarco seats from Poland and I am VERY happy with them for the price. Containment seat for me and a standard bucket for the rare passenger:



Bought some E36 specific seat mounts but ended up having to modify them significantly anyways, but I got both seats exactly where I wanted them:



In order to run seats like this, you need to run proper 5 or 6-point harnesses. But those harnesses need something to mount to. Let the slippery slope steepen. My original plan was to buy a 4-point bolt in roll bar or "half cage" I see it called sometimes. I wasn't crazy about this idea but it's better than a harness bar. However, the more I mulled it over, the worse I felt about that and it was a pretty expensive option so I started contemplating building something myself instead. I began looking into DOM pricing and it was surprisingly less than I had expected. I have a friend with a tubing bender with a 1.75" die and he was happy to let me borrow it so everything started falling into place and I had a new plan in motion.

I decided I'd build my own 4-point roll bar and weld it into the car. I asked around for some advice on that and was quickly talked out of going that route. I concluded that my only sensible option was to just go all out and build a proper 6-point roll cage following NASA/Spec3 guidelines. The more I thought about it, the more it made sense. Not that I necessarily plan on entering any race series myself, but at least the car would be set up for it should it ever go that route, whether its me or the next guy who owns this thing.

I've always wanted to build a roll cage, and I had a chunk of time to devote to it so I just dove right in. I had about 11 days before my upcoming track day and I made it my mission to finish the car up in time for that. It was a very motivating deadline and I spent many, many hours over those next 11 days doing the following work. I researched and studied the NASA roll cage requirement data thoroughly and figured out how I wanted to build it. Tried to learn the basics of the tubing bender and at a certain point just had to start cutting and bending:



The very first piece to bend was the main hoop, which is a pretty complex piece to figure out since it has 4 bends that need to be in very specific spots and you only really have one shot at it. I triple checked my measurements and luckily had a successful outcome! Main hoop bent and test fit, very happy (and relieved) with it:





With that mocked up, I could then start mapping out and building my 4 floor boxes and rear bar plates. The floor boxes are tacked into place while I build the rest of the cage, and then they later get cut out so that the entire cage can drop 5" allowing enough clearance to weld the upper portions of all the bars that normally sit very snug to the roof, and then they get fitted back in and finish welded:








I didn't have a tubing notcher so I printed out a bunch of different notch templates at different angles and had a little Sally's Corner Art's and Crafts session making those:





With the main hoop and rear bars fit up and tacked into place, I could start figuring out the A-pillar bars. These were very tricky to figure out as they have multiple bends in different planes, but was able to figure it out and was very happy with how they turned out. In the third pic below you can see I also have the windshield bar tacked in:





Made some bracing bars for the main hoop to A-pillar and A-pillar to windshield bar:



The curved bars are for helmet clearance. Allows the bar to swoop out of the way. Seems minor but actually made a big difference in clearance:



Door bars starting to take shape. These took forever to figure out and get to fit just right:



I reached a point where most everything was tacked into place and I final welded as much of the upper portion of the cage as I could, and then I cut the floor boxes out so that the cage could drop down 5" and finish welding all the tubes 360 degrees around:




Got it back up onto the boxes and got everything else final welded! I added the main hoop diagonal and harness bar last:






Dashboard modified and fitted. You'll noticed I also hit all of the welded areas with self etching primer (ignore the white paint, I was trying to be a hero and prepaint portions of the cage but failed terribly haha):




Seat and harness mounted! Getting all the harness belt mounting points sorted out took a lot of work too, had to build reinforcement backing plates for 4 of the 6 belts that mount to eye bolts.





Also built a little center vent delete gauge panel out of aluminum. I relocated my window switches there and have space for 3 gauges. Only have coolant temp for now but oil pressure and oil temp will come soon:







At this point, it was mainly just little odds and ends that needed to be buttoned up and the car was ready for track time! The cage isn't 100% done yet, I still need to finish plating in the door bars, adding a dash bar and a rear diagonal bar and paint the whole thing which will come soon, but it was at least to a point where I could go do some track days with it. I went hard and finished up JUST in time to make it out to Buttonwillow on Black Friday, it was a mad dash to get it all done but got the car out in the sunshine and hosed off the afternoon before the event:



I was definitely feeling excited and nervous simultaneously about taking it out on track since so much had changed with the car so quickly. I also hadn't driven on track in almost a year so I figured it would take me a while to find a groove and gain some confidence back. I got to Buttonwillow early on Friday morning (Nov 24th) and took it pretty easy the first session, just giving the car a good shakedown and didn't have any issues so I started pushing myself and the car harder with each session and was driving it to my skill limit by the end of the day. The car feels incredible, I didn't have a single issue with it and am so pleased with how it did!



Not that I was necessarily striving for a new PB, but I managed to squeeze out a 2:03.96 at Buttonwillow CW13 which was a nice cherry on top of a fun and successful shakedown day out there. Lots of room for improvement - Here is a video of that lap: https://www.youtube.com/watch?v=TAQqAjeU0ZI



Two days later I was off to Laguna Seca! I scored a $99 track day and couldn't pass it up, so I had two back to back track days and it worked out great. With the car feeling so good at Buttonwillow, I basically just left the car on the trailer with everything loaded up and just went straight to Laguna Seca. Once again, the car was an absolute champ and handled all the abuse without a hiccup. I love this track, the amount of speed you can hold through the cambered turns and of course the Corkscrew. Managed to set a new PB on my literal last lap of the day - ran a 1:46.85 which is nearly 7 seconds faster than my best lap in my E30. I was pretty stoked on that. Here is a video of that lap: https://www.youtube.com/watch?v=UCFc5SW6q_Q

Overall, I couldn't have asked for a better weekend on track and had so much fun getting more acquainted with the car and gaining more experience. The whole build process leading up to this was a super challenging and rewarding experience too and I had a ton of fun learning how to build a roll cage and figuring out all the other changes. My main focus is to get more seat time, so once I complete the cage and get the passenger seat squared away I will probably not make too many more big changes to the car for some time. An LSD would be nice, maybe I'll try to make that happen. Wow, that was a lot of typing, props to whoever made it through all of that. Until next time!