yea your right but the tuner side in me wants genuine parts that will give me the performance i want. trying to make my tegi JDM but not too much, so i want a few Mugen/Spoon parts. plus i rarely see guys with a Spoon header, Toda is ok but i would choose the Spoon or the ITR JDM 4-1 header before i cash up the money for the Toda one.

 

you want to shell out a crap load of money for a spoon that will be outperformed by something half the price? ok then.

 

There is more required in selecting a header than "which one is best." You have to consider all contributing factors, like: Compression, Cam's & Valvetrain, Future Mod's, etc.

Usually a 4-1 header gives you more power higher in the RPM range, at the cost of low end power. They also hang very low, and have a tendency to scrape on a daily driven car. A 4-2-1 header will give higher midrange power, and is much better for normal street conditions.

Try looking for dyno charts of the same setup as yours, with the different header's your considering. I.E. Stock B18c1 with Toda Header. Compare the power bands, and choose based on what is appealing to your desires.

Not to be a prick...

There is nothing to be gained by purchasing performance parts simply for a brand name, because nobody else has them, or because it makes your car closer to JDM. It might be good for show points, but in reality this only makes you a trend whore.

Look at your engine as a whole, and select your parts based on the setup you choose. Unless you've decided to go with high compression pistons, high lift cams, and move your power band up the RPM range - you won't gain anything noticeable going with a 4-1 header.