Archive for April, 2008

CamQuest 6 and Some Shopping for the Camaro

Sunday, April 6th, 2008

CamQuest software with my engine stats and estimated output.

I didn’t have much time for improvements to the Camaro because the next SCCA Solo II race was just two weekends away on April 13th.  While using the Comp Cams CamQuest 6 free software I made all of my decisions for my upgrades during my conversion to Electronic Fuel Injection, or EFI.  Upon launching the program, I put in my bore and stroke (4.030” and 3.484” respectively), my compression ratio of 10:1 (with the Fel-Pro steel shim gasket PN 1094), and the closest match to my Holley Stealth Ram intake that I found on the drop-down menu:  the TPIS Mini-Ram.  For head selection I chose the proper valve sizes (2.02” on intake and 1.60” on the exhaust) and described the combustion chamber as wedge with CNC porting.  A very cool feature of the software is that it allows you to enter your flow rates for known valve lifts and even will interpolate/extrapolate missing values based on those you know.  I had the flow rates for the Air Flow Research (AFR) 190 heads from the book Small Block Chevy Build-Ups by Chevy High Performance, so I entered these values in as well.  I entered my header size and selected from the drop down menu “High Torque, Good Economy, Idle, Overall Performance” for my cam selection.

 

The estimated torque and horsepower surprised me at 442 lb feet at 4000 RPM and 401 HP at 5500 RPM with the XTREME Fuel Injection XFI retrofit hydraulic roller camshaft using 1.6:1 rockers.  The particular grind was 260 XFI HR13 (PN 12-465-8).  Needless to say I’d be thrilled with 440 lb feet of torque for the autocross track out of my little 355 small block chevy.  I have no idea how accurate the program is, but I decided to go ahead with this cam (advertised as good for 1200-5200 RPM) and the full roller rockers.  I did a lot of research before deciding to get the Comp Cams Pro Magnum full roller steel rockers (PN 1302-16).  In the end I went with these rockers because they are chromemoly steel and therefore would not fatigue like aluminum over time yet have optimized geometry to be stiff yet lighter over the valve than aluminum rockers, thus decreasing reciprocating mass and increasing the potential rate of acceleration of the valvetrain.  I ordered the cam and rockers, new pushrods (PN 7809-16), a double roller timing set (PN 3100), and Comp Cam retro-fit hydraulic roller lifters (PN 853-16).  The nice thing about the software is that once you put in your engine stats and pick your cam, it provides all of the part numbers for everything else you need.  This was particularly nice for the pushrods because no-one would tell me what length I needed.  Everyone said due to engine variability it was impossible and I would need to order my entire valvetrain, buy a pushrod length checker, install everything, measure the length I need, and then order the pushrods.  You can imagine living in Hawaii I wasn’t interested in waiting on the shipping back and forth on this so I was glad to see the recommended pushrod length listed in the software.  I upgraded from the recommendations on the rockers (just roller-tip PN 1416-16) and the timing set (PN 2100).  While all of this stuff was a chunk of change, I really wanted an efficient engine that could rev quickly while keeping my stock bottom end for now, and I thought this was the most economical way to accomplish that in the Camaro.


Third Autocross Day in the Camaro Part 3

Thursday, April 3rd, 2008

Jons sweet ESP Camaro, good for 10th place today.

As it turns out, 44.449 was good for third place in the ESP class, 81st overall out of 113 competitors, and 75th overall after PAX.  I was thrilled with this outcome for my third race, and was starting to feel like the 1968 Camaro could be competitive if only I could bring up my skills and dial the car in.  Although there was a wide gap between me and the first and second place competitors in ESP, there were three other competitors in the class, including two Mustangs that I was faster than on that day.

C6 Z06 

There were 12 domestic cars out of a field of 113 total racers, so about 10% of the cars were domestics.  The breakdown was six Chevrolets consisting of 3 Corvettes (two C6s, driven by Randy and the Z06 driven by Jay and one C5 Z06 driven by Mitch) and 3 Camaros (my first generation and two fourth gen Camaros).  Pontiac was representing with two third gen Firebirds (one of which was driven by my new buddy Rick, who invited me to hang out in the “Musclecar Tent” he puts up every race day).  Ford had two Mustang entrants (one Fox body and one new Mustang) and there was a single Dodge Neon R/T as well as a single Saturn Ion Redline.  Of all of the Domestics, Jon from the ESP class in his 4th Gen Camaro SS finished first again at 13th overall that PAXed to 10th.  Next was Jay in the C6 Z06 at 21st overall and PAXing to 19th.  As usual Charlie was very competitive in his bone stock 4th Gen Camaro which was 39th overall but PAXed to 22nd.  So again about 10% of the cars were domestics and only a single domestic car got into the top ten standing for the day.  The abundance and relative dominance of the imports creates a certain camaraderie among the guys driving domestic cars, which is fun.



 

Third Autocross Day in the Camaro Part 2

Wednesday, April 2nd, 2008

Camaro autocross at Aloha Stadium 

I decided to start with 32 lbs of pressure in all four tires.  During my first run, I had a first—I hit my first cones while autocrossing.  In fact, I finished with a 48.232 s time but hit two cones, so was awarded a 52.232 official time.  I felt one of the cones as it went under my right rear tire, but wasn’t sure where I hit the other.  After returning to the grid, I reviewed my map and where I hit the cone as well as where I thought I was fast and where I thought I was slow.  I also envisioned myself racing through the course using my map as a guide for where and when to turn, and how I wanted my lines to come out.  I started trying to imagine where I might want to execute a “late apex” because there was a straight-away after some turns into which I wanted to have as much speed as possible.  The two corners where I thought this most important were out of the first hairpin turn for the short straightaway and then out of the second hairpin turn before the slalom.  This concept is covered in detail in the book “Secrets of Solo Racing” by Henry Watts.  I also left the air pressure in my front tires at 34 lbs which is where it had risen by virtue of being heated up during the run, and maintained my rear tires at 32 lbs of pressure by letting a little air out of each after my first run. 

 SCCA solo II autocross map 3-30-08

My next run was clean, and I finished with a time of 46.568 s.  Again upon returning to the grid I reviewed all of my gauges to ensure the car was operationally sound and then checked my tires.  This time I kept my front tires at 34 lbs but dropped the rear tires to 30 lbs.  After checking the car, I spent some more time reviewing my map in the grid.  The result was that my third run was clean and clocked at 46.174.  I was improving with each run but was quite a way from making an impact in my class.  During my routine review of my gauges I noticed the car was running hot and the voltage was down—sure signs I had thrown a belt somewhere out on the course.  I had a spare, so quickly ran to my toolbox and grabbed a few wrenches and the spare belt before dashing back to the grid and putting the belt on the car.  For my fourth run I concentrated on staying in control while in the car, and pulled out a clean run at 44.449 s!  Upon seeing the time on the board I threw my fist up—I was thrilled to have pulled off such an improvement in my last run, which I was sure would put me in good standing in my class.  Unfortunately I noticed upon returning to the pit area I was running hot again—I had thrown the belt that runs the water pump and alternator again.  I had time to find the belt and put it back on before run funs, but when I threw it again during my first fun run I decided to call it a day.  I was disgusted enough that I didn’t even record my fun run time.