Archive for April, 2008

Holley Stealth Ram, Commander 950 EFI and Cam Swap Shopping List

Wednesday, April 23rd, 2008

comp cams retro roller hydrualic lifters 853-16 

Since I had a bent valvestem in the ‘68 Camaro and the head had to come off to be repaired, and I had three months before the next SCCA Solo II autocross event here in Honolulu, I decided to take the plunge into the Electronic Fuel Injection (EFI) realm that I had been planning for over a year.  The first thing I did was make sure I had as many things ordered as I could think of that I knew I needed for the conversion to EFI.  I had already ordered the Comp Cams Camshaft (PN 12-465-8), retro roller lifters (PN 853-16), pushrods (PN 7809-16), timing chain set (PN 3100), and the full roller rockers (PN 1416-16) discussed in an earlier blog, and they were all in my possession by now.  Additionally, I had a Holley Stealth Ram intake, with fuel rails, injectors, a wiring harness, upper plenum, and with a BBK/Edelbrock 58mm throttle body that I had purchased used on eBay.  I had to order the gaskets that mate the intake manifold with the upper plenum (Holley PN 108-119).

 

I had the GM small cap computer-controlled distributor with an MSD external coil (MSD Blaster GM coil PN 8226) and MSD Street Fire spark plug wires (MSD PN 5570).  The MAP, IAT, and coolant temp sensors can be sourced from your local auto parts store since they are OEM for ’92 Camaro (and many other applications).  I had already installed the Commander 950 along with the Bosch wide band oxygen sensor (Holley PN 534-197) and the Holley in dash Air/Fuel ratio meter (Holley PN 534-200).  I had installed the wiring harness at that time and since the MAP sensor was a simple plug-in, that was installed as well by plugging it into the wiring harness and running a vacuum line off the carb to the sensor.  It was not secured anywhere in the engine bay yet, just handing off wiring harness.  For fuel plumbing, I had purchased a Walbro external in-line pump rated at 255 LPH (PN GSL-392), an OEM-style fuel filter (PN GF481), five feet of 3/8” rubber hose for fuel injection (rated SAE J30), and two five foot long 3/8” steel brake lines, pre-flared with tube nuts on them already.



 

My Fourth SCCA Autocross Day Part 2

Tuesday, April 15th, 2008

2001 Trans Am WS6 in SCCA autocross competition 

 

When it was time for the drivers of heat number three to autocross, I put my car “on grid” and prepped to race.  I started off with 34 lbs of pressure in all four tires and put some chalk on them so I could see if they were rolling over at all.  Since the Trans Am has a much lower torque curve than the ’68 Camaro, I decided to try my first run in second gear.  Some of my fellow competitors mentioned they did this in third generation F bodies and C4 and C5 Corvettes so it seemed worth a try.  In my first run, I came out of the slalom pretty hot and used the ABS before heading into the hairpin turn.  I was clean with no cones and a time of 34.845 s.  I was definitely not as smooth as I should have been.

 

For run number two I decided to go with first gear because I didn’t quite have the torque I wanted coming out of some of the slow sections of the course in second gear.  The rear tires seemed to have the chalk I applied still running right onto the tread so I let air out of them all the way down to 28 lbs, but I maintained the front tire pressure at 34 lbs.  On my second run my time improved by over four tenths to 34.402 s.  On the grid I let a little air from the front tires, bringing them down to 32 lbs, while maintaining the rear tires at the 28 lbs.  On my third run, I decided to try more speed after the slalom and came into the hairpin after the slalom too hot again, this time sliding deep into the turn with the ABS hammering away.  This strategy wasn’t working as I ended up slower on the third run by about eight tenths at 35.248 s.  I needed to pull it together for the fourth run or risk finishing very near dead last on the day.  I didn’t take air out of the front tires, so they were at 34 lbs of pressure while I let even more air out of the rear tires down to 26 lbs.  I finally put a decent run together by trying to be a little smoother and less abrupt in my inputs to the Trans Am.  I finished with a clean 33.474 s, good for third in the small CP class of four drivers. 

 

2001 Trans Am WS6 in SCCA autocross competition 

 

We had 113 racers show up for SCCA Solo II in O’ahu on April 13th, and my time was only good enough for 94th overall.  Worse, staying in the CP class (PAX 0.864) for the points even though the Trans Am could have raced in ESP (PAX 0.841) wasn’t helping me out since with the PAX my time was 103rd!  I had an overall expectation to continue to improve with each outing at the track so was a little disappointed with my finish, but given the circumstances of not knowing how to drive the Trans Am and moving into the tougher CP class I wasn’t really surprised that I took a step back either.  During my fun runs I did get some level of consistency from the Trans Am: in 5 runs I was clean on all and ran a best of 33.024 s and a slowest of 33.760 s.  I missed the ’68 Camaro for sure, and was determined to have it ready for the next race day.  I had a full three months until the next SCCA Solo II outing—July 13th.


My Fourth SCCA Autocross Day Part I

Monday, April 14th, 2008

 4-13-08 SCCA autocross Solo II Honolulu HI

 

Although I was without my ’68 Camaro for my fourth SCCA autocross event, showing up in the ’01 Trans Am WS-6 on the morning of the 13th and tech’ing in was uneventful.  Although the Trans Am would be legal in ESP, I decided to race in CP since there is a year-long points race and I would be spending most of the year in my ’68 Camaro which is not legal in ESP.  This time my map covered all of the area that we race, and I was able to get all of the cones down pretty well while I walked the course.  The course started off to the right with a few cones set up in an exaggerated slalom, then entered into a narrow section that required a little weaving but was fast if you could stay steady through it.  A sweeping 180 degree turn brought you back around and through a relative long slalom followed by a turn to the left, then a hairpin turn followed by a turn to the right before a hairpin exit from the course. 

 

I didn’t expect to be able to perform as well in the Trans Am as in my ’68 Camaro mostly because I knew the suspension was a lot softer and I had no experience racing the Trans Am.  Since this was only my 4th SCCA race and my autocrossing skills were still infantile, I didn’t figure I was going to be able to switch between the two cars without missing a beat on the track.  My first autocross day in December of 2007 with the ’68 and ’98 Camaros taught me that.  I was, however, very interested to see how well the 315s in the rear and 275s up front would grab the blacktop in an autocross event.  I was racing in the afternoon heat so watched some of the morning racing and hung out in Rick’s American Muscle tent the rest of the time.