Dynomoter Model: Skunk2's Superflow Chassis Dynamoter
Testing & Installation: Luke Munnell
2008 Honda Civic Si
Pros:
The latest Civic Si is powered by Honda's K20Z3, a motor nearly identical to the 200hp K20Z1 and K20A2 of the stateside RSX Type S and Euro-spec Civic Type R. The 'Z3's 11.0:1 compression bottomend and high-flowing head give it a fat, juicy 197hp powerband right from the factory, making the '06-and newer-Si an efficient, powerful commuter in stock trim, and a genuine force to be reckoned with when modified
Cons:
Despite extensive mechanical advancements offered by Honda's K-series engines, enthusiasts attempting to modify their K-powered streetcars for big power will find huge hurdles to clear if maintaining legality and streetability. In response to federally mandated clean air standards and public demands for fuel efficiency and reliability, automakers are fitting newer cars with increasingly stringent onboard diagnostic (OBD) systems. As we saw in our first installment of Power Pages with this car in the May '08 issue, making power in newer engines isn't as easy as it used to be.
Notes:
After fitting our Si with an intake, header/high-flow cat combo, and after-cat exhaust for the May issue's Power Pages, we were left wanting more power. The 12 top-end ponies and the nearly 20 lb-ft of mid-range torque we picked up made a noticeable difference in the Civics' performance, but based on what some tuners were producing from the K with just a little work, we felt confident there was more power to be made, without getting too crazy.
Dyno 1: Baseline
2008 Honda Civic Si: Part Two
Peak HP: 184.3 / Peak TQ: 129.8
Hondata ECU Reflash
Pros:
Installation is a cinch, turnaround time was fast, and the reflash delivered what it promised-a huge jump in mid-range power and torque; as much as 27 whp and 21 lb-ft of torque! Not to mention it completely flies under the cop radar and can be reflashed back to stock if need be.
Cons:
The fact that there is turnaround time at all...but that's just because we're impatient.
Parts:
Besides stock ECU, none
Tools
10mm socket and wrench, extension
Installation Time
10 minutes to remove/install the ECU, 1-2 business day turnaround for shipping.
Notes
As we pointed out in our previous installment of Power Pages with the Si, ECU tuning is absolutely critical in maximizing the benefits of certain upgrades done to newer, OBD 2 cars. The secret to Hondata's reflash lies in slight cam and ignition timing changes, leaner air/fuel ratios, and in their creation of a "VTEC window" which allows VTEC to engage at the most efficient time for a given throttle position between 4,500 rpm and 5,800 rpm-right where the K20Z3's stock tune lacks power.
Dyno 2: Hondata ECU Reflash
Peak HP: 185.4 / Peak TQ: 138.1
Horsepower Gain
* 2,500 to 3,500 HP range: -1.5 to 2
* 3,500 to 5,500 HP range: -6 to 27
* 5,500 to redline HP range: 1 to 22
Torque Gain
* 2,000 to 3,500 TQ range: -2 to 2
* 3,500 to 5,500 TQ range: -6 to 19.1