Long Time Dream Fulfillment: E30 Street and Track Car Combo

[CubbyChowder]

Thanks guys! Been making minor progress here and there since my last update, taking it on night runs on the back roads when I can to get some miles on it. It feels like it runs super solid while driving but I'm still troubleshooting a misfire situation with the car. The engine shakes and bucks a bit at idle and you can hear it misfire, especially when standing near the exhaust (can hear it puttering). Idle sits at a steady ~600rpm according to the tach, no surging or fluctuating. When I open the throttle by hand and hold it steady at a higher RPM, you can feel it misfire. I'd say it happens about once every 1-2 seconds. Seems to get slightly worse as it warms up. Car accelerates very smoothly and I don't feel any misfiring upon acceleration.

Built a smoke tester out of a soldering iron and pickle jar as seen on YouTube, and found a vacuum leak coming from the valve cover gasket of all places, so I replaced that and felt no difference. Everything else looked good but I will try another leak test tomorrow. Cleaned ICV with no improvement. I know it can be AFM, CPS, TPS, o2 sensor, coil, plugs/wires, etc. so I definitely still have some troubleshooting to do. Did a compression test, within 3psi of 180psi across all 6 cylinders, so that was reassuring. Any wisdom or input would be appreciated.

Gonna be a couple more weeks before it's street legal but it's so fun to drive! It feels awesome and I can't wait to get all the interior bits back together.

[moatilliatta]

Replace injectors?
rebuilt AFM?
oxygen sensor?
a lot of them have a sputter every few seconds

[CubbyChowder]

Long time no update! I haven't done too much to the E30 since my last post BUT I did have my first track day out at Buttonwillow Raceway last Sunday, June 27th and had an absolute blast. The car did so good, I am so proud of it. This was my first time driving on track so the first two sessions consisted of me following an instructor around the track at a pretty slow pace just to establish a good line and get familiar with the track, and the rest of the day I just got to drive my heart out. My instructor let me ride passenger in his Miata on one of his fast sessions and that helped tremendously with my approach. By the end of the day I was pushing the car way harder than I thought I'd be able to, it just felt so planted! The Falken Azenis RT660's were awesome. I also installed some PFC 08 brake pads in the front before the event and they grabbed hard all day and never faded.

Overall I got over 2 hours of track time and even had the entire track to myself and two other cars for a full 30 minutes, it was epic. The car is very much still a work in progress but I am so happy with how it performed and that it held up as well as it did, especially considering how much work has gone into the car up to this point and how many different components I've touched along the way.

Loaded up the evening before:



Back at camp after my first session. It was a hot one, temps reached 108 out there:



And a quick screen grab from some GoPro footage, passing my instructor in his Miata:



The ONLY issue I had all day was the coolant overflowing on me a few times because it was so hot out there and my aux fan wasn't kicking on so the expansion tank would fill up and spill over a bit once I parked the car and turned it off. I addressed this today by hooking up an extra defroster switch to my high speed fan wire so now I can manually turn on the AUX fan when I want. Definitely have some things I want to accomplish before my next event out there on July 25th. I'm hooked!

[AWDBOB]

Very stoked to see you get to enjoy the car on track already. A build like this has been a dream of my own for a long time.

[CubbyChowder]

Very stoked to see you get to enjoy the car on track already. A build like this has been a dream of my own for a long time.

Thank you man!

[CubbyChowder]

I left my first track day last month with a list of things I wanted to add/change with the car before it's next outing. I have my second track day coming up this Sunday the 25th out at Buttonwillow Raceway and I've gotten most of my to-do list checked off and the car is pretty much ready to go!

Trailering the car there made me realize how inconvenient strapping the car down was, so I built some strap tie down hooks that bolt in between the rear shock and trailing arm. I later painted them yellow and installed them:



The main thing I wanted to do was upgrade my radiator. I was running the stock late model radiator that I pulled out of the parts convertible and I had no idea how old it was and it was the only component of the entire cooling system that isn't new. Definitely don't want a radiator failure out on track so I sprung for an all aluminum 2-row CSF E36 radiator and got that installed. Forgot to take a pic until after it was already in the car. Had to build a new upper mount using random rubber bushings I found in my shop:



In that pic you can also see the new VDO temp sender in the thermostat housing. Then I plumbed in the new VDO oil pressure sender. I remote mounted it using an oil pressure adapter from Race German and an 18" braided steel line. Then I built a simple bracket to mount the pressure sender under the frame rail near the horn. Bad picture but you get the idea:



Then came some wiring and alas, a satisfying before and after:




Super excited to have that all back together for now! Here's a closer look at the new setup. I was trying to find a happy medium of street/track use and I'm pretty happy with how it came together. Got the aux fan switch in the upper left, OBC delete magnetic phone mount for monitoring lap times on track and controlling tunes on the street, coolant temp and oil pressure gauges and finally a simple bluetooth controller interface that replaces the head unit. This controller will get hooked up to an amplifier that will power the 4 speakers, and it'll just connect to my phone whenever I'm driving. Should work pretty sweet once it's all done.



Can't wait for Sunday!

[Joeyz31]

That turned out awesome man! I am bout to ditch my mechanical gauges for a similar setup so it was great to read through. The car seems to be coming along great! Sent from my iPhone using Tapatalk

[amcp]

Thats exactly how Im doing my gauges. The radio delete plate it perfect for it!

[CubbyChowder]

Happy to say that I had another successful track day on Sunday! The car held up great to the abuse and I feel like I gained quite a bit of experience. This track day was definitely a bit more intimidating as I was pushing myself harder through all the turns and braking later and later. It was a hot one out there, reached 102F in the later sessions and the car felt less predictable, I ended up going off track multiple times throughout the day. I was able to shave over 4 seconds off my fastest time from the first track day in June though (2:13.71 vs. 2:18ish), so that felt good! They let me bump up to a faster group halfway through the day which was cool.



I put together a little video of a few laps throughout the day, mostly just so I have something to look back on in the future. My GoPro angle kinda sucks at times but there are two laps from two different sessions (sessions 2 and 3) - Session 2 was the slower group but that's where I got my fastest lap of the day (2:13.71). I believe I could've gotten an even faster lap had I not kept getting stuck behind cars but I really shouldn't even be focusing on that this early on. Session 3 was the faster group and you can see me chasing the yellow Mustang. Then at the end of the video you can see me fly off track a couple times haha. Oops.

video: https://youtu.be/Ekr8piE6Q-E

[E30auddie]

This was a really good read and was well worth not getting anything done at work for the afternoon haha. Just got a VERY rough late model 318i sedan roller for a new project! Having a hard time finding time and motivation to really get working on it so far haha. I'm hoping keeping up with your build thread will help with that! Car is looking awesome though and looking forward to more updates!

[econti]

I ended up going off track multiple times throughout the day

Just call it accidental rallying

[Jb325is]

Really like your approach to this, and the fact that you're starting off with a well-prepped, mildly modded e30 to develop yourself before the car.

[CubbyChowder]

^^ thanks guys!

I have my third track day coming up on Sunday and I finally had some time to get my new Vibrant muffler installed today! It's the $120 Vibrant 1148 and honestly I'm super happy with how it sounds, it's exactly what I wanted.

The stock muffler was beyond ugly and falling apart:




I ordered a y-pipe to merge from the stock dual 1.75" pipes into the Vibrant's single 2.5" pipe, it took some modification to work and I had to fab up some hangers but I got there in the end and hit it with some header paint:



So much better!



As for the sound, I took a gamble with this one and lucked out. It's exactly what I was hoping for. It's not obnoxious, it's not raspy, it's not even really that loud. It's slightly louder but deeper/throatier now, and sounds especially nice in the higher RPMs, which I spend a lot of time in out at the track. This modification does absolutely nothing for me other than make me smile when I hear the noises and I'm perfectly fine with that.

[E30auddie]

I have admit that I'm extremely vain when it comes to the exhaust note of any motorized vehicle lol. If it doesn't sound good, I don't really want it haha.

New exhaust looks awesome though!!

[moatilliatta]

May want to extend the tips to keep from burning, and soot if the bumper.

We need a sound clip!