Dyno Page: Skunk2 Megapower S2000 Header

Skunk2 recently released their new 4-2-1 equal length header for the S2000. Introductory pricing was at $750 which made it on our 'to-do' list for dyno testing. Test car was a stock 2007 S2000 with 50k miles. We performed a baseline before and after the header install, then began installing supporting mods and Hondata Flashpro tuning for favorable results.

Specs:

• Equal length 4-2-1 design with sequential pairing, stepped runners and 2.5" collector. 
• T-304 polished stainless  steel
• Weight 15 lbs. vs stock 21 lbs.
• Comes with a new collector gasket and matching diameter female 2.5" collector flange (to be welded onto a custom exhaust if you choose to do so)

Durability:

• With 26 dyno pulls and 4.6hrs of track abuse at Buttonwillow and Thunderhill the header has held up fine.

Appearance:

• Merge collectors are mated up and welded with precision and manufactured with close tolerances. No header at this price offers this type of quality. 
• We're not fans of chrome, however after running the car the header color changes to a bluish hue which looks much nicer.

Install:

• Due to the length of the exhaust runners, it takes up the majority of the area between the cylinder head and frame rail.
• Requires the removal of the OEM heatshield which protects the fuse box, a/c lines and heater hoses. This item cannot be re-installed.
• Requires removal of the passenger side engine mount bracket to hang header. The header will not go in without engine mount removal. The clearance from header to engine mount is about 1/4" but sufficient enough to prevent the header from rubbing under heavy load (track conditions).
• Clearance from header to passenger side frame is roughly 1". After two dozen dyno pulls and two track days, paint in that area is coming off. A thermal coating or custom heat-shield could be good preventative measures.

Temporarily, we bolted up and tested a 63mm test pipe and Invida V2 catback exhaust. 

• Stock Baseline = green dotted line 
• Skunk2 Header, 63mm Test Pipe, Invidia V2 Exhaust (No Tuning)= red dotted line
• Skunk2 Header, 63mm Test Pipe, Invidia V2 Exhaust, Hondata Flashpro Tuned = green solid line

After, we removed the smaller diameter exhaust and fabbed up a custom 3" header back exhaust with v-band connections and our trick swivel turndown / dolphin tip. Racetracks in Northern California like Mazda Laguna Seca Raceway, Infineon and Thunderhill have sound limitations ranging from 92db to about 115db. Having a tip the can be rotated away from sound level sensors increases the chances of passing the test without welding additional resonators or mufflers, sacrificing exhaust flow and power output.

The Final Numbers:

BT's Conclusion:

Crunching Numbers:

Remember our philosophy of 'Cost vs Benefit' to hp building? That hasn't changed. Keeping this in mind, we performed these tests with a stock intake, filter and airbox. The OEM air box, with proper do-it-yourself mods yield comparable improvements to aftermarket brands but at a lower cost. We don't like how much space the OEM box takes up, but it is a well engineered and functional part.

Here are the numbers for our test:

Retail Price:

$750 Skunk Megapower Header

$695 Hondata Flashpro

$1100 BT Custom 3" Headerback Exhaust (made to order)

$2545 ÷ 25hp = $101.80

At near $100 per HP, this a bargain for NA engine tuning. We didn't include tuning rates since rates vary geographically. Through BlackTrax, you'd be under $110 per HP.

Cons:

The involved sweat equity install, non-CARB Legal and exposure to heat given off by the header are the three negative characteristics we found.

  

Pros: 

Factoring in the performance, quality and price point, the Skunk2 Megapower Header is hands down the best valued off-the-shelf header on the market today. Comparisons made between the 63mm exhaust and 75mm exhaust reveal notable gains in the mid-range rpm which allows for lower VTEC engagement. This is a good header for those looking for the broadest power band increases. Inherent in the sequential pairing design, the exhaust tone is original sounding with audible wave separations at low rpm that quickly ramp up to a smooth yet raspy note from 4,000 rpm to redline. 

With supporting exhaust mods and Flashpro tuning, AP2's are now seeing 235 horsepower at the wheels. Mid-range gains make this 2800 lb car fun to drive on the street and quite usable on the track. VTEC is currently set at 4800rpm however it can be dropped down to 4200rpm if preferred.