Thunderhill Track Day

I’m still working through all the data from Saturday’s HPDE event at Thunderhill but I figured I’d share some pictures, video and feedback.

Overall the day was a huge success! Despite having gone to Thunderhill for over 15yrs (as a spectator/passenger rider), this was basically my first time driving this track, and in a car I’m still dialing in and getting used to. Unfortunately since I signed up last minute, NCRC (event organizer) was completely booked but they were able to get me into the advanced (open) group given my experience at Laguna and familiarity with racing techniques/etiquette. I didn’t have an instructor per say, but rather went off my experience as a passenger and having my friend/passenger point the turns-out, especially the blind ones (which Thunderhill has a decent amount of).
Since we got a late start I only got 4 of 5 sessions in. My first session was a wash as most of it was spent learning the track and developing a driving line. Also we discovered the breather system was having major issues (more of that down below). The second session I was getting faster, more comfortable with the car but still having oil breather issues. The third session was even better but still having oil breather problems. The fourth and final session was great.

I hit the dyno last Friday to make sure the rebuilt transmission is in working order and to make sure the new ignition system was running as expected. Plus, I was able to see how much power was choked from running the Laguna Seca spec exhaust (<90db’s) I built a month or so ago. Everything worked perfectly and the engine lost 5whp from the exhaust system so it now makes exactly 195whp and 128ft/lbs trq. It’s definitely not a beast but with the FD and 15″ wheels, it should hold its own.

Fuel System
Everything appeared to be working perfectly. I’m still going over the data logs (fuel pressure in turns) but generally speaking, the fuel system didn’t experience any of the issues I had a Laguna Seca. The addition of the internal baffle (water bottle) seemed to work great, as did the 2-way vent. In terms of consumption, the engine is burned six gallons of gas after running 3.5 20min sessions.

Ignition System
The new Hondata CPR system worked great! No ignition breakups, no misfires, nothing. It’s worked flawlessly. It’s also great to know that I no longer have to deal with worn-out sparkplug wires, caps, rotors, igniters, coils and sparkplugs. The Denso coils should last several years and the Iridium sparkplugs should last a season.

Rebuilt Transmission
The transmission felt great. The only issue was a slight grid going into 5th when I would rev 4th gear above 9k rpms. The likely culprit is the Comp stage 1.5 clutch not releasing quick enough at high rpms. Regardless, it was so minor that it wasn’t a huge issue and was controlled by keeping the 4-5 shift under 9k rpms. Also the trans oil temps surprisingly hovered in the 170-180degF range. I was expecting it would be much higher.

15″ wheels w/ semi-used NT01’s
As mentioned previously, and after speaking with Mark Hein, I wanted to try running my spare set of 15″ wheels with the 5.5FD. Mark said that’s how they ran it at Spa and it worked great. The gearing is super short now, but I’m able to run a lower ride height and better utilize the rear suspension/geometry. This was a great enhancement, and especially with the relatively low power.

Initial (Moton) suspension settings
After noticing how unbalanced the rear felt at Laguna, I discovered the front and rear shock settings were completely out of whack. I reset everything back the initial settings and the car felt MUCH better. It’s hard to say if it was the tires or I was just getting comfortable with the car, but overall it was much more predictable then last time. The rear still gets pretty light, especially over peaky turns or during rapid left/right sweepers but hopefully that can be dialed-in with the suspension. Xian – thoughts? Also I still need to hit an alignment rack as I have no idea what the settings are currently…

AiM MXL2 Display w/ GPS & AiM Smartycam
The display and camera were great. Honestly the amount of data is simply stunning. I still need to tweak some settings and am waiting on some software/firmware updates to enable all the features but thus far it’s proved invaluable. Aside from logging the OE sensors within the Hondata, I’m also able to log them within the AiM MXL2. Additionally, I can also log the added AiM sensors for (water temp, oil temp, oil pressure, fuel pressure, transmission temp, front brake pressure, rear brake pressure, lambda and EGT).

Below is a link to the YouTube video of my 2:10 lap w/2565lbs:

Here’s some pictures of the car, driving, and w/redGSRguys K-series ITR:

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s