2008 Honda Civic Si Sedan - Project Si: The Bolt-on Bruiser - Honda Tuning Magazine

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Project Evasive Si
In the first installment of Project Evasive Si, we gave you a comprehensive breakdown of a group of performance parts we handpicked for Mike Chang's '08 Si sedan. Already an avid track regular, Mike has visited the winner's circle his fair share of times following heated battles in his respective class. But as we mentioned previously, he was looking to up the ante and produce more power and torque to take on tougher competition. Lightly armed with just an exhaust, header, and air filter overseen by a standard Hondata reflash, we set out to find a proper combination of performance goods that would show sound improvement, especially in the midrange. One other detail; the car was to remain completely street friendly. After some research and some sound advice from Toda, we chose to use the following:

Htup_1104_01_o+2008_honda_civic_si_sedan+project_evasive_si   |   2008 Honda Civic Si Sedan - Project Si: The Bolt-on Bruiser, Pt. 2

  • Toda A3 cams
  • Toda valvesprings
  • Toda timing chain and tensioner
  • BluePrint Racing valves, retainers, and head prep
  • Skunk2 header
  • Hondata FlashPro
  • OEM Honda RRC (CTR) intake manifold, slightly enlarged throttle body (65mm)

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With all of the new parts installed on the newly refinished head by BluePrint (stock ports), we set an appointment with the one person we were sure could make this performance combination work as a team on the dyno: Doug MacMillan of Hondata. Doug has been at the forefront of Honda performance tuning for years, and his race records, accolades, laundry list of automotive accomplishments, and his legendary reputation in the performance industry are all well deserved, and we'd be hard-pressed to find a better man for the job. Rather than taking the car to a tuner, sitting quietly in the waiting room, and keeping his fingers crossed, Mike was hoping to actually learn more about where his car is at currently, what could be pulled out of it with proper tuning, and any future options for this K20.

Htup_1104_05_o+2008_honda_civic_si_sedan+intake   |   2008 Honda Civic Si Sedan - Project Si: The Bolt-on Bruiser, Pt. 2

Arriving at Church Automotive Testing, Doug and Mike removed the wheels and mounted the Si to the DynaPack. While some may argue that DynaPacks read "too high" or that they're easily manipulated into spitting out astounding numbers, we were here for two reasons. First, to find out how much power we were making and at what rpm, and secondly, to tune the car meticulously to harness the most useable power for a road race/street car. Peak numbers and worrying about what someone's roommates, brothers, "homie" made during a tuning session was of no concern-and other than throwing clever verbal jabs at one another from behind a computer screen on a Honda forum, don't amount to much in the real world.

Htup_1104_06_o+2008_honda_civic_si_sedan+wheel   |   2008 Honda Civic Si Sedan - Project Si: The Bolt-on Bruiser, Pt. 2

Doug pulled out his laptop and iPhone, checked engine vitals, and soon got underway with the first pass. Obviously, the original reflash wasn't optimized for the new cams and other changes, but the car pulled safely to redline and the numbers already looked very promising. Impressed, Doug was confident there was plenty more power to be pulled from the 2.0L. He plugged in the new FlashPro unit, had Mike register the product online, and began making changes to the fuel and timing curves in search of more power. Due to the FlashPro's ability to micromanage, Doug was able to make very slight adjustments to wring every last little bit of power out of the engine.

Htup_1104_08_o+2008_honda_civic_si_sedan+testing   |   2008 Honda Civic Si Sedan - Project Si: The Bolt-on Bruiser, Pt. 2

As the tuning session was coming to a close, the peak power numbers (I know it's eating you alive) averaged at 256.6, with torque measuring at just over 181 ft-lb. The first dyno pull that still relied on the original reflash buried stock Civic Si numbers, but the use of the new FlashPro to fine-tune the new parts improved the output even further.

Htup_1104_07_o+2008_honda_civic_si_sedan+voltex   |   2008 Honda Civic Si Sedan - Project Si: The Bolt-on Bruiser, Pt. 2

What's with the cheater pipe?!
Before you jump online and start posting about how Honda Tuning cheated with an extension pipe, rest assured, every single dyno run up to this point was done with the factory intake using an aftermarket air filter and T1R snorkel that reaches down to the grille area. However, Doug wanted to attach what he calls the "magic intake" in order to gather a little more info. It's painfully obvious that a regular street car could never actually use a pipe like this, but it has the keen ability to offer insight on whatever car it's attached to. Using the extension lets us know if there are any major restrictions within the Civic's intake system. While the factory airbox isn't exactly free-flowing, Mike likes the idea of having an almost bone stock engine bay for the times that he drives the car on the street. Other than a small piece of silicone hose connecting the throttle body to the airbox, you'd never have a clue that this car is packing over 250 hp. As Doug performed a few more pulls utilizing the huge intake, he found that there was in fact a restriction somewhere along the intake path. With an increase in power and torque at almost every point of the powerband, a larger throttle body and open-element intake might be the key to more power. Also, the factory injectors were getting close to maximum duty cycle, so Doug suggested a set of Acura RDX injectors for further tuning.

Htup_1104_10_o+2008_honda_civic_si_sedan+hondata   |   2008 Honda Civic Si Sedan - Project Si: The Bolt-on Bruiser, Pt. 2

With the tuning session finished, the factory airbox was reinstalled and Mike took the car for a spin around the block. The ear-to-ear smile that was plastered all over his face upon his return confirmed the newfound power was in fact very "useable." As Mike stated "It just feels like a completely different car now. The throttle, the power delivery, I mean everything!" The reborn Si was able to muster a 2-second improvement in lap times at Super Lap Battle this year, resulting in a 2:02.4; inching ever closer to the coveted 2-minute mark. What's even more impressive is the fact that Mike's Si tears through Buttonwillow on street tires.

So, what's next?
Good question. Mike has felt the surge of additional power and is now considering changing out his 2.0L block for a K24 bottom end loaded with additional upgrades. We'll keep you posted as the search for more power and faster times continues.

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