2018 Portland Adult Soapbox Derby (Page 2 of 2)

July 13th:

Mirror fairings designed by Jimmy Jones were installed on the MKII in time for the test session.

The mirror fairings were mage from small plastic funnels. Cost of this mod was $1.18....for the pair.

The brake upgrade on the MKII required some minor body modifications.

July 13th testing:

The MKV features brake calipers on both front wheels.

This setup designed and built by Chris Kouba resulted in excellent stopping power.

This is the steering system designed and built by Chris for the MKV. Due to the very limited cockpit space, the steering yoke operates on a horizontal push pull plane rather than the standard automobile type steering.

Testing July 13th:

Our test site features a nice uphill climb following the long straight downhill section. This is a great test run with the steeper grade uphill portion aiding in the slowing of the cars. An important factor in the event of brake failure or brake fade. Without braking the cars will crest the top of the hill, but are slowed enough even if the brakes fail completely the car can be run off the road onto the shoulder and stopped.

Here's Chris MKV, and Jenny MKI at the end of the first run. This photo was taken from the bottom of the uphill shut down section.

We only had one slight mechanical malfunction during the entire day of testing. It happened during a tow back and resulted in a trailer back instead of a successful tow back. Jenny Burns did an awesome job of keeping the MKI out of the ditch! It was definitely a successful day of testing!

All three of the competitive fleet in a row:

Jenny after we started to get the brake drag issue figured out.  You can tell this by the smile on her face:

Jeff, clearly concentrating in the MkII:

What does the MkV look like?  Here is a shot prior to loading up for test day:

When I sat in them back to back, it makes the MkI feel enormous.

As Bill said, it was a good day all-in-all.  All the cars performed well right up until we broke them, although the MkII seems to have survived the best.  The MkI needs new wheel fairings and the MkV needed a stub axle welded back on after it failed during the towback incident.  The MkV also needs its own set of wheel fairings, an extension for the under-chassis floorpan, and I want to experiment with a few aero tricks and see what they may bring.  The good news is we all went home in one piece and we know the changes we made to comply with the new rules (especially the new braking requirement) aren't hurting us performance-wise.

The hard numbers were comparable to last year- the MkI ran 39mph, MkII hit mid-30's, and the MkV ran 41.  I think there's a little more headroom with a little more aero work on the MkI and a few more tweaks to the MkV.  In any case, we won't be any slower this year.

I also need to extend an enormous thank you to those who make the time on the hill possible.  It literally wouldn't be happening without Bill doing all the behind the scenes, extremely non-glamorous errands that he does.  He also shows up at the shop for work sessions to get his entry (and mine) into one piece.  I really appreciate all the effort and energy he puts into this- I couldn't do it without him.

Also stepping up in a big way this year is Mr Jeff Burns.  Jeff has jumped in head-first this year to support the revisions to the MkI for Jenny to run down the hill.  He has put in an enormous amount of effort to get the car to where it is and for that, my hat is tipped!  He's even developed some mad new skillz, and if anyone needs some sheet metal work, drop him a line.  I'm certain he's watched at least 4 Youtube videos on it at this point, so he's pretty much a master craftsman.

Another round of thanks to Jenny, Dennis, and Beau, for their help in facilitating the test day.  Whether it was unloading, helping set up, flagging traffic, or hauling our sleds back up the hill, we also couldn't do this without them.

And thanks to the person who truly makes this whole circus possible, my wife Bethany.  She lets me indulge the inner 12 year old and lets me disappear for hours (and days) on end into the shop to work on these creations.  With everything else that's going on in our lives, I have very little spare bandwidth, and she allows me to soak it all up with gravity cars.  THANK YOU B!!!

Friday was another good day of testing.  We made 11 passes down our short course close in the Gorge, with all three drivers and cars in attendance, along with Jeff and the little Burnses.

All three drivers with their respective rides:

We were able to break a few more things today, but in general, things went very well.  We still have some speed to dig out of the Mk I and think we have a lead to accomplish this.  From there it will need some additional body panel and aero work and then get painted for its final livery and graphics applied.

Jenny belted into the Mk I:

The Mk II was a different beast altogether.  It ran 47 mph all day long.  Didn't matter who was driving it, didn't matter where they drove.  All its top speeds were in the 47.something range.  We did add some weight for the final two passes and bumped it up to 49 mph, so there's something worth looking into there.  All in all, it was an excellent day for it and Bill was quite happy!

Bill approves, the Mk II:

Bill rolling through a 47 mph pass:

https://photos.google.com/share/AF1QipO … ZQbWg1elZn

The Mk V had another interesting day.  After a 50.7 mph first pass, it broke its brake cable for the second, drifting around a corner to high center on the road side.  I was told it appeared very dramatic from the outside but it was quite calm and collected during the maneuvers.  After sitting out a few passes, the Mk I donated its brake cable (needs to be replaced anyway) and which enabled the Mk V to make a few more passes.  The speed was still there, knocking out runs consistently in the low 50's, with Jeff Burns taking FTD on the last pass.

The Mk V out in the open:

We experimented with weights and a few other settings, and while we still have work to do, we are reasonably prepared for the actual derby.  We still have some midnight oil to burn, but we do enjoy the ride!

Thanks again to Bill, Jenny, and Jeff (and Johnny and Jessica) for a great day in the hills!

The Scuderia Kouba fleet:

Race day is quickly approaching and we have ramped up our work to get fully prepared!

Scuderia Kouba has scheduled a day for car pushing practice with the United States Marine Corps. Sounds pretty cool huh? On Wednesday morning August 8th we will be setting up for practice in the Vancouver Mall parking lot. We plan to use a small portion of the parking area on the west side of the mall, close to Thurston Way in Vancouver. Thurston Way is one of the Vancouver Mall exits off of SR500.

We plan to be at the mall location by 8:30 am with all the Scuderia Kouba cars. We need to unload and get set up and ready for the Marines arrival by 9:00 am. I estimate the practice session will last no longer than one hour as the Marines have a busy schedule of their own. After that it will just be a matter of loading the cars back up and cleaning up the test site. I realize mid morning middle of the week is not a good time for most, but if you have time available and would like to help us out with this endeavor please let me know. Any help will be greatly appreciated! 

===========Bill

Wednesday August 8th at 9:00 AM was push practice with the Marines!

To funny