One Lap of America Civic Si

[OneLapCivicSi]

I’ve been lurking and learning here at CivicX for the last 2 years, and it’s time for me to hopefully give a bit back to the community. This thread will be a place for us to share our journey as we campaign my 2019 Civic Si in the 2021 Tire Rack One Lap of America.

The One Lap is an 8 day long event that covers 3000+ miles of public road transits between 8-10 different motorsports events (mostly road course time trials). The competition is all on the track, but the car must be driven the whole distance and compete on one set of tires. More information on the event can be found at http://www.onelapofamerica.com/ and https://www.facebook.com/OneLapOfAmerica/

My codriver Chris and I have been racing national autocross for many years, and you can follow our teams exploits at https://www.facebook.com/ontheledgeracing/ and @ontheledgeracing on Instagram. We’ve also done some Lemon’s racing, and our longer term goals involve completing the build of my E36 M3 for endurance racing with World Racing League.

We think the 10th gen civic Si will be a good platform for our first One Lap as it’s a great combination of performance, comfort, space, and safety (easy to maximize performance and safe at the limit). Our goal is to finish the event and have a car that is more than capable of winning the Economy class or finishing near the top of Mid Priced Sedan (not sure how they will class us). Our plan is to tackle handling and reliability first and then focus on making safe power from the stock turbo with flex fuel.

I’m starting this thread after we’ve been working on the car for a while, so over the next several of posts I’ll share what we’ve done to the car so far. One lap starts a little over 7 weeks from now, and we still have a good amount of testing and work to get ready. We will cover the remainder of the build and then also update this thread with our progress as we run the event. Finally, here is the car as it sat at the end of Jan. before our first track day of 2021.

-Andy

 

[OneLapCivicSi]

We decided to run the One Lap while following event coverage in 2019 right after I bought the Si as a daily driver. I swore when I bought the Si that I wouldn’t race it, but it really impressed me with how much fun it was to drive. I was also excited by how much the platform seemed to respond to relatively simple mods. Apparently, we weren’t the only ones excited by the 2019 One Lap, because by late September of 2019, very shortly after registration for the 2020 event opened, we were scrambling to register and reserve a spot. Unfortunately, we were a bit late and ended up 12th on the waitlist. While we were disappointed to not have a definite spot in the event, many former participants suggested we plan for it anyways because there are often lots of spots that open up.

Below you can see where we arrived with our plan for mods. I’ll walk through some of why we chose what we did in the future as I cover the installs, but we reached out to several vendors for advice prior to making our final decisions.

Mod List/current status

Suspension/brakes/wheel/tire:

• Custom coilovers from Redshift Motorsports (450f/650r spring rates) – done
• 22m eibach rear swaybar – done
• Accord endlinks – done
• Whiteline adj. balljoints – done
• Whiteline anti lift kit – done
• SPC rear control arms – done
• Carbotech XP10 front and XP8 rear brake pads – done
• 18x9 Motegi Traklite wheels – done
• 255/35/18 Michelin PS4S – done

Power/Drivetrain:

• Civic Type R clutch – done
• Perrin Motor mount inserts – done
• Sirimoto Oil Cooler – done
• Burger Motorsports Intercooler – done
• RV6 Catted DP and Front pipe – pending
• K-tuner – done
• Flex Fuel – pending
• Custom Tune – pending

We began working on the car early in 2020, and we managed to make one track day after installing the rear swaybar, brake pads, motor mount inserts, and Michelin PS4s on the stock wheels and giving the car a basic wheel alignment. The day was wet, but it was obvious the car had lots of potential. It was good to get started on the project, but our plans were derailed soon after by COVID. The 2020 One Lap was postponed, and while disappointing, this gave us a lot more time to prep and for parts to arrive.

 

[WhiskeyTango]

Subbed. I did Hot Rod Power Tour a few years back with a buddy of mine and it was amazing. Literally the only thing missing was some racing. This looks to have it all. I am just reckless enough to try some shit like this too ?

 

[JO3L]

Looking forward to hearing more about your experience in this event. Best of luck out there!

Just curious if you have any inside info on the vehicles you might be up against in your class?

 

[Unity Performance]

Good to see you on here, Andy! Looking forward to seeing updates on your thread

Didn't know your mod list when we were chatting via email, the Mishi oil cooler stands out to me - is this a custom kit you fabbed up, or did you retrofit the CTR Oil Cooler?

 

[OneLapCivicSi]

Good to see you on here, Andy! Looking forward to seeing updates on your thread

Didn't know your mod list when we were chatting via email, the Mishi IC stands out to me - is this a a custom kit you fabbed up, or did you retrofit the CTR Oil Cooler?

Good catch! It's the Sirimoto oil cooler and the Burger Motorsports intercooler. I edited the post to reflect that.

 

[OneLapCivicSi]

Summer of 2020 was spent sourcing parts, and as the weather began to cool off a bit in November we began to work hard on prepping the car. We really wanted to focus on building a reliable car so the first thing we tackled was the clutch. At the recommendation of many we went with the Type R setup from NA Performance, and it has turned out awesome.

I’ve been doing all my own car work for a long time, and I’m fortunate to have a pretty nice garage setup to work in. However, it’s always nerve racking taking apart a new car that’s also a daily driver. Fortunately, the install was actually pretty straightforward thanks to the help of the ACT tutorial video The subframe came off easy, and the transmission broke free as soon as we removed all the bolts. Some of the transmission case bolts were hard to reach, but overall it wasn’t anywhere near as bad as the ND Miata we worked on in 2018. Working at a reasonable pace and with the help of at times 2 friends, we completed the install in about 10 hrs.

This seems safe right? Lol… we used a real strap.

I’ve included a photo comparing the stock Si clutch/flywheel to the Type R and you can see how NA Performance very neatly welds on the Si starter gear ring onto the single mass Type R flywheel. I also measured the width of the disc; the Type R disk is a little over 1 mm wider. This doesn’t matter for us in One Lap, but for anyone thinking about using this setup for an STH autocross build, be aware that increasing the surface area of the disk isn’t allowed. The stock dual mass flywheel is a chunk; the new setup weighs almost 11 lbs less!

I wasn’t really expecting the clutch to change much driving wise. We did it to hold reliable power on track, but I have to say is one of the best driver mods you can make. It engages so much smoother than with the unspring disk/dual mass stock setup. I swear I could feel the stock flywheel shudder on every shift. I’m not sure why Honda chose this design, but I’d love to hear the engineering logic there. The car also revs way faster which simplifies heel toe rev matching.

-Andy

 

[Boss002]

Good luck this year. As a fellow 2019 Si owner, Tirerack salesman, and One Lap class winner, I will likely be stopping by for the skid pads and autocross since my teammate can't come across the border so I had to skip this year.

 

[OneLapCivicSi]

Good luck this year. As a fellow 2019 Si owner, Tirerack salesman, and One Lap class winner, I will likely be stopping by for the skid pads and autocross since my teammate can't come across the border so I had to skip this year.

Bummer to hear you won't be able to make it this year. I've heard it has been a real challenge for all the international entries this year. You'll have to come say hi if you make it out to the event.

 

[OneLapCivicSi]

Continuing on with the reliability theme, at the beginning of December we installed the intercooler and oil cooler. The install on these was straight forward with the exception of me not noticing that initially the o-ring on the filter relocation kit was not seated correctly. Upon initial startup I was horrified to hear what sounded like a shower underneath the car. After a lot of swearing and cleanup, I reset the o-ring and everything worked great.

Next up we added a PRL intake tube, and reflashed with a K-Tuner and the TSP Stage 1 tune. We’ll get a custom done when we add the flex fuel sensor and downpipe. The new tune certainly woke the car up, and all the new torque is a lot more fun than stock. I can’t wait to see what flex fuel and a good tune can do.

 

[OneLapCivicSi]

We started searching for a damper solution for the car early in the planning process. As long time autoxers, this is our comfort zone, and we’ve had experience with a wide range of solutions including some high end stuff like MCS. I didn’t want to spend MCS money for the One Lap since the plan with this car is to run the event and de-mod back to a daily driver setup.

We were very fortunate to find an outstanding solution from Chris Shenefield at Redshift Motorsports. Chris takes BC Racing dampers and rebuilds them to perform like digressive racing dampers. Key to this is that the damper provides high levels of force at relatively slower speed movements (transitions left to right on a track) and lower force at high speed movements (bumps, track curbing, etc.). We went with the single adjustable solution for simplicity and cost. Chris helped us pick a spring rate starting point of 8K front and 12K rear. We felt like this would be a good compromise of capability on the track and still tolerable for the transits.

This was the first set of dampers Redshift has done for the Civic Si platform, and there were a couple of things we had to work through. We ended up using the regular BC racing Civic Si shock body for the front and adapting the Type R body for the rear. Using the Type R damper in the rear gave us a larger shaft diameter which allows for much better damping curves. Chris also had to do quite a bit of R&D to get the fronts correct as this was the first time he had rebuilt a BC damper with the 38 mm pistons.

We also had issues with the rear spring length that took some R&D. We started out with 170 mm rear springs (stock BC rear for the Si is 190 mm), but with the much higher spring rate, the car sat way too high even with the adjuster set to its lowest position. The first pass solution to this was to replace the rear threaded collar section with a BC racing helper spring setup. Fortunately this got the ride height in the right range while we worked out what length spring to actually go with. The helper spring has the added advantage of keeping the spring captive without having to limit rear shock travel. We ran our first track event of the season on this setup without issue, but the final solution was threaded collar + helper spring + 140 mm spring.

Along with the coilovers we also installed SPC adjustable rear camber arms (OMG the bolts are hard to get to!), and we used D2 adaptive damper bypass units to avoid any lights on the dash. We roughed in the alignment, put on the new wheels/tires, and then went to get it done right before our first track day of the year. We weren't totally happy with only being able to get -2.1/-2.4 for front camber. We were hoping for closer to -3 without using the adjustable ball joints, but this was as much as we could squeeze out of the camber plates and factory slotted mounts. We set the rear camber to a little less than the fronts and put a slight toe in front and rear for stability. Overall we are super happy with how it all turned out. Next post I'll cover some of what we learned running the new suspension setup on track.

 

[rbobby]

This is great info, thank you for sharing.

 

[OneLapCivicSi]

The first event of the year for the Civic was the NASA Texas Season Opener at MSR Houston on Jan 30-31. MSR Houston is our home track, and it made for a comfortable place to dial in the new setup. The track allows for safe running in both directions, and NASA ran the event clockwise on Sat and counterclockwise on Sunday. On the Ledge Racing had four drivers at the event so we had several of our autocross cars there to help serve as a baseline including my codriver Chris L’s STX FRS.

Bottom line, the Civic was faster than we expected, and by morning of day 2 we were one of the fastest cars in the combine HPDE 3/4 group. Collecting point bys from expensive cars on race tires in our 4 door sedan on Michelins is tremendous fun. We didn’t reach the cars full potential on day 1, but on day 2 we were able to put in some good, clean, fast laps (Andy – 1:52.2, Chris – 1:53.3). The Si was faster than any of the other cars we brought, although I think with a little more “send” we could have caught the Si in the STX FRS.

For this event we kept the Si in TSP Map 2 sport mode the whole time since we were mainly focused on finding the right range for the shock settings. We played with the damper settings over the two days and we ended up going fastest with front and rear both set two clicks off full stiff. The balance of the car was excellent; it’s easy to dive hard into decreasing radius high speed corners, yet loose enough under harder trail-braking to tuck the nose tighter on turn in to slower stuff. We also had one wet session and the car was equally easy to drive in the wet.

Data logs showed sustained lateral G loads of just over 1.1, but I think there’s more grip to unlock with additional front camber. Looking at some of the event pictures shows the outside front rolled over more than I’d like. There was also still a lot of room for improvement under hard braking (the FRS brakes way better).

Overall it was a great weekend; NASA puts on a smooth, well run event. We had great weather, no offs, a fast car, a couple things to improve on, and a lot of fun. Next up was some more suspension tweaks and a trip to NOLA Motorsports Park to scout our first track we will see on the One Lap.

 

[OneLapCivicSi]

Looking at the tire wear (front tire shown below) and photos of the car on track from MSR, it was pretty clear that we needed to try and add more camber to the front of the car. While the Michelins survived without too much excessive wear, we were clearly asking a lot from the outside shoulders. We ordered a set of Whiteline lower ball joints and the Whiteline anti-lift kit (ALK). Hopefully the added camber from the ball joints and the dynamic camber gain from the extra caster will be enough.

Pressing the rear bushing off the lower control arm gave a good excuse to buy a press for the shop. The 12 ton press from Northern Tool worked really well. I also added the wheels to it as well so it’s easy to roll under the lift for storage.

The Whiteline parts went right onto the lower control arm without issue. We set the ball joints up for max camber, lubed up the ALK bushings. and tightened everything down per the instructions. However, in the back of my mind when I ordered the ALK, I was wondering how great of an idea it really is to change caster by moving the angle of the lower control arm. This seems to me like it’s going to put the front bushing under stress/bind. This was evident by how much it changed the alignment. The instructions tell you to immediately get an alignment, and I can see why. We measured over 1.5 in of toe out after we put it all back together! (see photo below... doesn't do it justice... it looked ridiculous)

Our normal alignment shop was moving locations and not availabe, so we borrowed a set of Paco Motorsports hub stands from an OTLR teammate. This was the first time I used hub stands for an alignment, and I’m in love. They are remarkably easy to use; having all that space to adjust things without the tires on is awesome. We gained about a half degree of camber up front. It’s hard to compare between the two alignment techniques, but on the stands I measured an average of -2.7 degrees up front and set the rear to -1.9 degrees. I dialed in 1/16” an inch of toe in front and rear.

First impressions of the new parts setup were ok. I was happy with the camber gain, but after a couple days of driving the ALK bushings were already sounding like they need re-greasing. I also got the occasional pop from the front. It sounded like binding, but I held off on judging until we got it on track. Next up was the NASA event at NOLA Motorsports Park on March 13/14.

 

[Unity Performance]

Following for an update

Sponsored