So the biggest restriction on my stock engine set-up is my exhaust header, I could net a good 10+ ponies just by getting a better flowing header, match that to a decent exhaust, tuned and the rest and we're talking perhaps 25hp. Our JDM based Facelift models unfortunately didn't get the extra exhaust pipe diameter like the yanks did on the TSX, it's the thing I should be concentrating on next. The biggest and best in the business is the Toda 4-2-1, it's race proven, robust, and been the blueprints for many other replicas like the offering from Weapon-R. On the note of Weapon-R, I don't like the company and their branding, their "dyno charts" are always proven wrong, they have silly slogans like "Make Big Power!" and use semi-glad model pics and bad Photoshop work - it's just not a company I'll buy from (but the header is by all accounts good). The cheapest budget offering is from DC Sports, so it's cheap, you'll get decent gains, it's also had many documented issues like the flex pipe cracking and leaks - while purported fixed, I can rule that right out. Another big name for the CL9 is the venerable Comptech header (now CT-Engineering), again there were a few issues with leaks and what not which are apparently fixed in new versions, it's gains aren't quite up there with the Toda/Weapon-R/PLM but they're good. Probably not for me though. Then there's the cheap wonderboy, the PLM header, gains have been proven to pretty much on par with the king Toda, but they aren't exactly made consistent, sometimes they need a little work to fit properly - but once they are, I haven't really heard of any problems. PLM is known for good bang for buck, hit and miss quality. There's a few other rare offerings, like the Mugen (Facelift version being far better) running at 4 figures once imported, and many established companies have generic K-Series headers that can be made to fit. Everyone who's followed my build so far knows I research to hell, so here's the question and let's say the gains are the same: Do I go for a £300-350 PLM header, I'm sure I'll make it work and it'd stick on the car okay. Or do I drop £900 on the renowned and made-to-order Toda header shipped straight from Japan? It's a big price difference, but I like backing quality companies - I can't be parts proud with a PLM, but would I be silly to drop that money on an exhaust header when gains are comparable for a lot less?