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.




