It’s been a while since we had an update on this car and a lot of people were starting to wonder what happened to it. Between the many obstacles to overcome, developing some custom parts, going back and forth on decisions, the owner of the car (and myself) having two having kids, this became a sideline project in the shop. Our usual chats shifted from the K20 swap to sharing our experiences raising two young children. Although progress was made slowly throughout, I wanted Part 3 to be the final part of the blog.
The team arrived back in Colorado Springs on Saturday, June 15th and we were greeted at COS airport by some really cool window artwork promoting this year’s race. After leaving the airport, we immediately headed over to our home-away-from-home: Winslow BMW of Colorado Springs and we were met with another fun surprise; this year’s “Signature” car, a BMW Z3M coupe and “Parade of Champions” car, a new BMW i5 M60 electric performance sedan. The liveries for both cars were unique for the 102nd Running of the Pikes Peak International Hill Climb. Legendary PPIHC Hall Of Fame Inductee, Clint Vahsholtz, was this year’s driver of the “Parade of Champions” car; which meant that after the race on Sunday he would lead all of the competitors down from the summit of the mountain back to the start-line. It’s an incredible honor, and I can think of no one better for the job considering Clint has raced Pikes Peak 30 times. And out of those 30 times, he’s won his class 24 times and he was King of the Mountain in 2020. Wow!
Following several successful planned test days at our home track of Sonoma Raceway in April and May, we finally arrived at the first Official Test Weekend ahead of the 102nd Running of the Pikes Peak International Hill Climb (PPIHC). This weekend took place on Saturday and Sunday June 1st-2nd, and as a rookie I was informed by the event-organizers that my performance across both days would be evaluated in order to make a final determination of my eligibility to race on June 23rd. No pressure or anything, but game on.
Over the 2023 winter holiday break is when things got really serious for our Pikes Peak car. We used the downtime to get a lot done, including a full rebuild of our Drexler rear diff.
It’s been over 3 years since I put the Honda K24 into our Lotus Exige and it was the first car that I made an engine harness for. Although the harness was reliable and never gave me any issues, I felt that my harness building skills have improved much since then. What I really wanted to do was get rid of all of the unused wiring and the mess under the dash.
It’s been over 3 years since I put the Honda K24 into our Lotus Exige and it was the first car that I made an engine harness for. Although the harness was reliable and never gave me any issues, I felt that my harness building skills have improved much since then. What I really wanted to do was get rid of all of the unused wiring and the mess under the dash.
A few months ago, we decided to register for this year’s 2021 Global Time Attack and Super Lap Battle Finals at Buttonwillow. The Exige wasn’t built for time attack, but we thought it would be a fun place to compete and see how capable the Lotus with a K-series really is; even if it is heavily outgunned in its class (because of the rule set, the car falls into Limited, a class that normally sees cars with forced induction engine setups making well over 600whp). We decided to set our own goal of a sub 1:50 lap, which may be the first naturally aspirated Elige to do so. The best time this car had done previously at Buttonwillow 13CW was a 1:51.7 on Falken RT660s.
We went into the month of August feeling excited for two reasons. First, our K24 swap was finally complete on the Lotus and after a solid shakedown at Laguna Seca in late July by Graham and Tom -- it was finally ready for wheel-to-wheel action. Second, we would have 2 race weekends take place relatively close to each other, August 1st and 2nd at Thunderhill and then August 22nd and 23rd at Sonoma.
In part two of the K24 swap, we were left waiting for the header to arrive. We ordered a Hytech 4-2-1 header specifically made for this swap, which took a little over a month to get, but was well worth the wait! It fit perfectly. Other than trimming the J-pipe to length it needs no modification to fit any muffler designed for this chassis. Once fitted, all we had to do was make an extension harness for the wideband o2 sensor.
When we left off in part one of the K24 swap, we had the engine in the car and started getting things connected. Although it seemed like it was close to being done, there was quite a bit left to do. We decided to keep the factory dual oil coolers. This may change in the future, but we wanted to make sure the temps were stable even on extremely hot days. Moving along on the track is one thing, but following closely behind another car in “dirty air” and it can get hot pretty quickly. Because these cars are known to over cool engine oil, we installed a thermostatic sandwich plate with a 200F thermostat to help maintain proper temps.
If you grew up in the 90s and were into cars, then you’ve heard of the Honda B-series engine and how amazing it was. It was the “hot rod” engine of its time and my gateway into modifying cars. The planning, researching, parts sourcing, building, and then seeing how it improved the car’s performance is what got me hooked. In the early 2000’s, Honda came out with something even better..
In Part 8, we were waiting on a driver net before we could have the tech inspection done. The Schroth net with the new quick release mechanism that we originally ordered was still undergoing testing and its availability was severely delayed. So, we went with a equally good option- Safecraft.
With a year of rebuilding and developing the Exige behind us, we were excited to begin our “winter project,” the roll cage. When the car came back from the last track event of the year (a very wet Laguna day), we gave it a good wash inside and out before getting into it. We also had to do some homework and make sure that what we build is safe and legal for the the local sanctioning bodies we plan to race with. We followed NASA’s Club Codes and Regulations handbook as a guide.
At the last two-day track day at Buttonwillow with Speed Ventures, shifting in the Exige started to get notchy. It would sometimes be difficult to get into gear, but we kept driving it. By the last session of the day, we were not able to get the car into gear after pulling off into paddock. If the engine was off, it would go into all gears, so we suspected it to be a failed clutch that was not fully disengaging...
Fuel starvation is a well known problem with this platform. It’s mostly noticeable on long left hand corners because the fuel pick up is on the left side of the tank. It’s typically not an issue if I keep the fuel tank full, but every time our got down to about 70%, it would starve. This can cause a lean condition and be harmful to the engine, especially with forced induction.
The Exige S is known for heat soaking and extremely high IATs (intake air temps). The stock intercooler is mounted on top of the hot engine and doesn’t get nearly enough airflow through the small roof scoop. It also doesn’t help that the hot air from the radiator exits in front of the windshield and makes its way into the roof. There are some things you can do to help like a larger intercooler, additional ducting from the side scoops, larger roof scoops, or adding fans to the intercooler…
This past Monday, June 24, we decided to take a team day-off to go to the track with Golden Gate Lotus Club. In addition to drives, meets, and fun outings, GGLC hosts great track & autocross events. Only three run groups, so you get SEVEN sessions! Not to mention, they always offer snacks, coffee, fruits, and sometimes even lunch!
Monday through Friday
7am to 4pm
