[rpoz-29]

I made 3 pulls on a dyno-jet dyno over the weekend. The car is all stock with a K&N filter. It has a little over 4,000 miles on it. I didn't plan to run the Camaro, but the other 2 projects I had in mind weren't ready. The first pull was 288.6 hp/307 lbft at the wheels. Pull 2 was 286.?? and 307.??. The third pull, I swapped the K&N for the AC the car came with. The hp was back to 288 and the torque was up to 311. The dyno operator mentioned that the engine was a bit leaner as well, indicating better flow with the AC. I've had the K&N on it for about 2,500 miles, it's clean and not over oiled. Does this surprise anyone?

[RedHardSupra]

heatsoak is a big issue when you combine a plastic housing with bad placement where you get no cooling (aka GTOs). it gets even worse if you have an integrated IAT sensor in your MAF housing, causing it to read much higher intake temps than what really occurs, pulling timing because of that, and reducing performance some more.

MAF's are very sensitive, and any mods will throw them off. my only mods were lid, filter, muffler and a z06 cam, and the car knocked throughout the full range of rpms, for any non-totally-lazy throttle inputs. all it needed was a MAF recalibration and the car literally woke up.

a lot of people think they're making things better, but they don't. what happens often is they add headers, which greatly increase airmass in midrange (aka peak tq already), and even with the computer's ability to learn and adapt, it will make it go lean enough that the car knocks, pull timing, and effectively becomes slower than originally.

yes, it sounds silly to retune things even in 'its just a filter' scenario, but the truth is that the computer is very eager to panic and reduce performance.