Spokes Autocross 2009 #4 San Marcos

April 27th, 2009

 

For my third outing with Spokes, I made sure to gas up the Camaro in San Marcos so I had a full tank while racing!  I pre-registered and got on the road on time so I showed up at the airport with no drama.  The ’68 Camaro knocked down 19 MPG mostly highway from the Texas A&M Riverside, home in Cedar Park, and to San Marcos.  Not bad, although could probably be better if I tuned it at all—I’m still running off the tune I downloaded from Holley with only a few tweaks around idle for stability. 

The course layout was published so I didn’t have to do my usual googlemap download and sketching during coursewalk.  I took the extra time I had from not having to map everything out to get some extra coursewalks.  I did four in all, by myself, and trying to imagine where I wanted my car, walking from the perspective of the driver’s seat (cutting cones on the left closely and leaving about 6 feet for cones on the right).  I drew the assignment to work heat two and race heat three so I decided to try to get a ride with someone during heat one.  The only car of interest to me on the course was the uber-Corvette of Troy Acosta in SSM (used to be SM2).  Troy had a line of folks wanting to ride with him but took me on his last ride.  What a ride it was!  I actually got a head rush from the acceleration and was a little dizzy but Troy obviously wasn’t as he piloted the modified C5 to a 49.136, which, by the end of the day, was less than two seconds off the pace of the Formula SAE cart with Travis Rouse at the wheel!  Thanks for the ride Troy!  By the end of the day, Troy’s Corvette was one of only two domestics to run faster than I did in the Camaro…but I’m getting ahead of myself.

 

course map at San Marcos for Spokes #4 2009

course map at San Marcos for Spokes #4 2009

 

The course was fast, and fun.  There were quite a few DNFs at the sharp right just before the 2 on the map, and lots of spectacular 360s because the racing surface transitions from concrete to newer cement in a couple different sections…and the car goes from lots of grip to lots less grip quickly!  I worked the cones between 5 and 6 on the map and had a very nice very of the entire course so had a pretty good mental map by the time heat three was ready to go.

 

I started with 36 PSI in all four of the Hoosier A6s, and set off on my first run.  I had a passenger (Sierra) and came into the transition to area 3 too fast.  I felt the rear get a little loose but the Camaro wasn’t swung around quite as far as I wanted so I decided to go with it and put a little more gas on…which was way too much.  I did a complete 180 and stalled the Camaro to boot.  I restarted, put it in reverse so I didn’t end up with a DNF, and finished the course in 68.608.  Super slow, but I wanted to get an official time rather than a DNF since I was the only car running in CP today.  The tires had taken a bit of heat but the fronts seemed to be happy at 38 PSI so I left them there while the rears I took down to 35 PSI based on the temps being a tad high in the middle of the rears.  Second run I also had a passenger and I was happy to run a 52.745 on a reasonably smooth run.  I felt there were places I could go faster for sure, and was dead set to improve on that run!

 

Forgelines and Hoosier A6s on the 68 Camaro

Forgelines and Hoosier A6s on the 68 Camaro

 

 

Well run three was solo but unfortunately slower at 53.343—I was too hot coming into the sections of the course with less grip and was just a little sloppier.  Run four Sierra was riding with me again and I was hopeful for a good run.  Sectors one and two were fast but I came into the left-right-left around 5 too hot and had to slow a whole bunch and ended up with a DNF as I decided not to clip the cone and drag it around the course.  Run five was solo again but with similar results—sloppy and running a 53.443 but also with a cone.

 

Heart of the Beast--Holley Stealth Ram in 68 Camaro

 

I was disappointed to not improve from run number two, but that bitter pill will be a good reminder next time out that it is far more important to be smooth than to be fast on the autocross course.  Overall, I won the uncontested CP class but finished 39th overall based on raw times, and 56th of 120 based on PAX.  I was pleased to see that I broke into the top 40 for the first time ever in an autocross in the Camaro.  Looking at the 38 drivers who ran faster than I did, there were only two domestic cars faster—Troy’s C5 Corvette, which obviously should be faster than my 40 year Camaro, and an ESP Mustang—which obviously should not be faster!  Oh well, that’s just an excuse to renew my goal of beating the Mustangs every time out!

Autocrossing at San Marcos Airport with Spokes

March 13th, 2009

Autocross course laid out by Andy Hollis at San Marcos Airport for Spokes.

 

Spokes (www.spokes.org) is the local autocrossing club in Austin, they use all of the SCCA classifications and most of the rules but are a little more lax with some of the rules and therefore a little more fun.  I missed their first outing of 2009 and was wrenching on the Camaro in an attempt to get it together for their second outing, but alas it was not to be.  So I saddled up my daily driver, the 2001 Pontiac Trans Am WS-6, for a little auto-x!  In terms of prep, I pretty much just checked the fluids and tire pressure and emptied the car out before heading to San Marcos in the morning.  It’s about an hour drive from where Cris and I settled in Cedar Park, TX, so I left just a bit after 7 AM.  The drive was enjoyable (down US35 toward San Antonio) and uneventful.  I arrived at the San Marcos Airport a bit after 8 AM and was waitlisted to race since they had a full registration. 

 

As I was waiting I met Ann Hollis, she the wife of Andy Hollis, autocrosser extraordinaire and instructor at Evolution Performance Driving School (http://www.evoschool.com/).  Andy has his own Wiki (http://en.wikipedia.org/wiki/Andy_Hollis) which is pretty cool!  Andy is a six-time SCCA Solo National Champion and was the designer of the course at San Marcos!  Anyway, Ann was very sweet and welcomed me to the region and introduced me to a whole slew of people (sorry I don’t remember all of your names!).  Ann is an accomplished autocrosser in her own right and is I believe also an instructor at Evolution…but she is modest and doesn’t have her own wiki, so I am not sure about the details.

 

Well, I made the “cut” (in fact I think all of us on the waitlist did) and was allowed to race my first time out with Spokes.  Tech inspection was uneventful so I was off to walk the course and try to map it out.  Prior to leaving in the morning I had printed an aerial photo of the airport space where we were racing from Google Earth.  As you can see from the scan, the course started out with a three-cone slalom to set up a roundabout on the right.  After the roundabout, there was a short straight with a turn to the right through a tight gate, which was followed by a sweeper back to the left.  Another fast turn to the right with a few cones up top and then a tight right turn before entering the long slalom, which ended with another chicane and then an offset slalom to end the course.

 

I worked the first heat, and was keeping my eye on the blue Corvette of Lance Adams in SS who was the first to run the course in under 60 seconds.  He managed a 59.818 s; at that point I decided if I could run within 10 seconds of that time I’d be doing pretty well, given that the Trans Am was almost certainly one of the heaviest cars at the track that day and that I was rolling on some bald Sumitomo HTR-Z (UTQG 160 A A) that would be replaced next week.  So I set my goal to break into the 60s.

 

On my first run I ran 73.866 s, slower than I had hoped for, but I did a conservative run and hit no cones (no sense making a fool of myself drifting all around the course in my first outing with Spokes!).  Run number two was over two seconds faster at 71.838 s, faster through all three sectors of the course.  I was feeling that the 60s where in reach.  I had a passenger for run number three (chicks dig the Trans Am!), and cut another second and a half off at 70.372 s.  I had another passenger for run number four (actually the boyfriend of first passenger) and made a fairly major mistake coming out of the first sweeping left turn too hot and nearly taking out an entire row of cones.  This forced me to come nearly to a complete stop to avoid the cones and killed my time.  Although I was faster through sectors one and three of the course, I added over two seconds in sector two, netting me a 71.750 s, the only run of the day in which I didn’t improve. 

 

My last two runs were solo, and I put together a 69.559 s run on my fifth run; I also had my fastest times of the day for sectors one and two on this run.  For my last run, I was about 0.150 s slower through sectors one and two (combined) but I shaved an entire seven tenths off in sector three, so finished with my best time of the day, a very satisfying 69.020 s.  I had improved on all but one run, hadn’t hit any cones on the day, and ran within 10 s of a very well-driven SS Class Corvette.  As an added bonus, I also beat both of the Mustangs that showed up (sorry Paul M!).  Add to that I met some great folks, all of whom were very nice and inviting, and I had a great day of racing!


Cyberdyne Digital Fuel Pressure Gauge

July 18th, 2008

Cyberdyne fuel pressure sending unit
Since I had two weeks before my next SCCA Solo II Autocross event in the 68 Camaro after United Airlines left me in Austin, TX and I missed my July 13th event, I decided to put a digital fuel pressure gauge in the Camaro so I could keep an eye on the fuel pressure generated by the Walbro 255 inline pump and the Holley fuel pressure regulator.  I wanted a digital gauge in red to match the Dakota Digital dash and the Holley Wide Band Air/Fuel Gauge I had already installed.  The best bang for the buck seemed to be Cyberdyne; their digital fuel pressure gauge for EFI reads from 20 to 100 PSI, comes with the sending unit and wiring, and can be found for under $100.  I needed an adaptor in the fuel line somewhere to tap the sending unit into. 

Cyberdyne fuel pressure gauge sending unit

The sending unit has 1/8th NPT threads and you can buy a pressure gauge adapter with either barbs or AN -6 fittings on either end but I decided to machine my own from brass with barbs to go inline in the 3/8ths rubber fuel-injection rated hose (SAE J30).  I put a ½ diameter brass rod in the lathe and bored the center out to 0.330” before turning down the ends to 0.375” on either end.  I left the center at 0.500” and also left the barbs at 0.440” with sixty degrees backcut and forty five degrees on the end going into the hose.  I radiused all of the cuts and put the tube in the milling machine to drill and tap the hole for the 1/8th NPT threads.  I also picked up a couple of stainless steel worm clamps to put the adapter in-line in the fuel hose.  I installed the gauge on the passenger side firewall with a plumbing clamp I found at the local hardware store and re-bent to fit securely over the unit with a single screw.  This is essential for proper gauge performance because the sending unit needs to be grounded, which the rubber fuel hose obviously doesn’t accomplish.  For the gauge mounting I simply drilled an additional hole in the 20 gauge sheet metal panel I had made to mount my Holley Digital Wideband Air Fuel gauge in the dash.  I also made an equally-space dimple in the center of the panel so the addition of a third gauge in the future will be easy.

Holley Wideband Air Fuel and Cyberdyne Fuel Pressure Gauges

Wiring the gauge was straightforward: I tapped into the twelve volt supply for the Air/Fuel Gauge as well as the ground while routing the sending unit wire through the firewall grommet with the wiring harness from the Holley Commander 950.  The gauge worked well and confirmed fuel pressure at about 41-42 PSI upon putting the key in the ignition position.  The fuel pressure regulator is vacuum referenced and with the car running at idle fuel pressure was around 35 PSI.  The gauge fit well into my red LED scheme and allowed me to monitor the fuel delivery system for problems which is critical when retrofitting the 68 Camaro with EFI so I was happy.