Tomei UEL Header |
The header is one of the biggest, if not THE biggest area to increase power on a naturally aspirated FR-S/86/BRZ. Other exhaust modifications do make a little bit of power, but do more for sound than anything else - the header is a different story.
When selecting a header for the FR-S/86/BRZ, there are to types to pick from - equal length or unequal length. equal vs unequal length refers to the length of the piping for each cylinder. An equal length header means that each of the exhaust runners are the same length, unequal length means they aren't the same length. An equal length header tends to make more peak power, but an unequal length header gives a little more torque down low in the rev range. In terms of sound, an unequal length header provides the classic Subaru rumble that we all know and love, where an equal length header creates a more smooth sound. Since I love the Subaru rumble, and because down low in the revs is where the FR-S needs more power the most, I opted to go for an unequal length, catless header.
While the header itself will create more power than any other exhaust modification on the FR-S/86/BRZ, there's an added bonus when it comes to tuning with a header. Up to this point, I've had the stage 1 OFT tune in my car, which is the most aggressive tune that OFT offers for the FR-S with the stock header in place. When you upgrade to an aftermarket header, you can move up to the stage 2 tune. If you upgrade to an aftermarket header with no catalytic converters, you can use the stage 2+ tune. From most of the dyno charts I've seen, a UEL catless header with a stage 2+ tune is generally good for 20-30 horsepower at the wheels - I believe it.
The finish and quality of the Tomei Expreme UEL header is excellent. The welds all look top notch, the finish on the exhaust runners is shiny and flawless, the thickness of the flanges is chunky and think, and the collector is free of any burs or imperfections. It isn't difficult to see why the Tomei header is one of the most popular options for the FR-S/86/BRZ. The quality is everything I hoped it would be and it comes at a price that's doable for most. It's more expensive than some of the other options out there, but this is one area of the exhaust where you shouldn't cheap out. The header has a big impact on overall sound and performance, so spending a little bit more to make sure you're getting something good is definitely worth it.
INSTALL / FITMENT
Install of the Tomei EUL header was a breeze largely thanks to the boxer engine in the FR-S/86/BRZ. You'd be hard pressed to find another vehicle with such easy access to all of the bolts since everything is literally right on the bottom of the engine.
The header itself fit perfectly. Mine required no adjustments for perfect fit, but there are 2 small bolts that can be loosened to adjust the overall width of the header for the perfect fit if needed. Everything is pretty straight forward, but if there are a few tips that can be provided, they are:
1- Soak the header studs in PB Blaster overnight. I did this just as a precaution, but they all came off with no trouble at all.
2- With a UEL header, one of the pipes restricts access to one of the header bolts and makes it really difficult to tighten. There's not enough space for a deep-well socket, the stud is too long to use a shallow 3/8 socket, and there's no room to get a wrench in there. The best solution I found was to use a 1/2" drive socket and a 1/2" breaker bar. The 1/2" socket is just deep enough to clear the header stud and the breaker bar is low profile enough to fit between the header pipes and allow you to tighten the bolt a little bit at a time. If anyone has a better way of doing this, please let me know.
3- Be careful when you bolt the over pipe back on. It's very easy to bolt it in place and not leave enough clearance between the over pipe and the chassis or the over pipe and the engine. Visibility is limited in these areas so make sure you feel around to check. If there isn't enough clearance, it'll rattle when the engine is under load (may or may not have done this myself and spent way too long trying to figure out why my car sounded broken).
The performance and sound of the Tomei Expreme UEL header is amazing. There's absolutely a massive difference in the power available - especially down low. The combination of the header and the stage 2+ tune bring the FR-S to the power level it should have had from the factory... It's unfortunate that you need to do so many modifications to get it there, but whatever.
As you'd expect with a catless header, depending on the rest of your exhaust system, it can be quite loud. Mine certainly was. Since my Greddy Revolution RS cat back is one of the louder cat-backs, and since my front pipe is also catless and unresonated, mine was too loud and had quite a bit of rasp. The winning combination for me was to put the stock front pipe back on, which eliminated the rasp and brought volume levels back to an acceptable level without noticeable loss in power.
All in all, the Tomei Expreme UEL header was a great purchase - one that I should've done a long time ago.