Product Description
Longtube design will not fit the stock exhaust center section. Part requires custom fit or one of the related X-Pipes shown below.The BimmerWorld View - Unlike older car models, BMW equipped the E9X M3 cars with good headers from the factory. It took absolutely every racing trick up our sleeves to gain power, but our new BimmerWorld Longtube headers produce proven results and are guaranteed to surpass expectations. Beyond putting out big power from stock engines (and even more from stroker and supercharged applications), our true equal-length headers change the shape of the exhaust sound, eliminating some of the muddiness of mismatched exhaust pulses for an intoxicating, crisp, and harmonious note.
As automotive technology advances and manufacturers focus on maximizing power output and fuel efficiency, modern cars have become more performance-optimized, making our job of producing upgraded products more difficult, however, with a bit of hard work and years of experience, we can always find power. Aside from forced induction, the exhaust system remains the best place to extract more power out of a modern BMW. Stock rear mufflers flow well, and you can significantly reduce weight and change the tone and volume of your exhaust by bolting on an aftermarket part, but it takes a fully-engineered system to maximize power output.
Our BimmerWorld E9X M3 Longtube Tri-Y Headers are the result of several years of design and iterative testing, making everything from minor dimensional adjustments to complete layout changes on order to produce the only truly effective product available:
- Computer Modeling - The first step in creating a performance header is determining exactly what the specific engine needs, based not only on power output curves, but also piston size, stroke, valve size, cam profiles, etc. A header processes the exhaust gasses, and to maximize the efficiency, we have to model the natural exhaust flow and create a system of eight cylinders pulse-timed to work together with the combined result greater than the individual parts. The result of this modeling process is a theoretical set of design parameters that are often good enough to go on even a pro-level racecar, but for us, with the goal of wringing out every last horsepower, this was only the beginning.
- Header Layout -The computer model suggested that the best gains would be achieved using a 4-to-1 design, in which four equal-length primaries merge into one collector. We built a set, dyno-tested engines and cars, and we were fairly happy with the result - good high-end horsepower on street cars and racecars, with both stock and stroker engines. Another set with a few slight revisions netted even greater results. However, late in the game our manufacturer suggested we revisit a Tri-Y design where primaries merge in pairs, then join in a final merge collector with the goal of producing more usable low-end torque. With many dollars and months invested, and the added expense of manufacturing a Tri-Y product, we were hesitant to change our path. With vast experience in restrictor-plate, small-bore racing, we decided to accept the change proposal - we're glad we did! Beyond its superior performance in the upper RPM range used on track and for racing, the low-end gains make this header system a fantastic street-car product as well, with big torque where you use it the most.
- In-Car Packaging - Fitting larger equal-length headers is a challenge, especially when retaining all street car components. To fully optimize the tubing length/volume and layout, we used a coordinate measuring machine (CMM) to create a computer rendering of the engine bay. The result is an exactly equal-length header that fits properly and produces power.
- Testing. Testing. (And More Testing) - After hours of engine and chassis dyno time, multiple sets of test parts, and seemingly endless phone conversations and email exchanges, we can confidently claim to have optimized this header system with little regard to time or expense. Call it obsessive, but the primary motivation of gaining an advantage over our competitors on the race track has resulted in the absolute best product available.
The dyno results speak for themselves. We publish the real results, measured at the wheels where you feel it (not the larger number calculated at the crank to wow you), with tight measurement constraints instead of common dyno trickery. The dyno chart in the product photo gallery shows the best runs from the same car on the same day with the following three configurations:
- Base Run (Green Line) -Pure stock car with an aftermarket rear muffler (same piece used for all tests). No software or any other modifications.
- Stock with X-Pipe (Blue Line) -Same stock car with our BimmerWorld Non-Catted Race X-Pipe, adapted to fit the stock headers. Additionally, we tuned the car with a custom Epic Motorsports calibration to provide the best possible result achievable with stock headers and an otherwise stock car.
- Headers with X-Pipe (Red Line) -The only change for this run was installation of our Longtube Tri-Y and a proper software calibration for the hardware change. So what do the headers do? A flat torque curve with improved power throughout the rev range and peak gains of 41Hp and 32ft-lb over stockand 11Hp and 11ft-lb over our best-case stock header system!
BimmerWorld E9X M3 Longtube Tri-Y Headers - Technical and Production Features
- Tri-Y Design - Cylinders are paired properly to assist in exhaust scavenging to maximize low-end torque and the area under the curve with no loss in high-end horsepower.
- Stepped Primary Tubes - Primaries step from 1-5/8" to 1-3/4". The smaller diameter boosts low-end torque while the step to the larger diameter in the primary frees the exhaust gasses for higher RPM flow.
- Merge Collector - 2" secondary pipes flow into a merge collector with a 2.5" venturi and 3" tailring to promote scavenging.
- Precision Production Fixture - Production fixtures are laser cut and exceedingly robust, with contact points every few inches to ensure the part you receive fits perfectly as designed.
- Laser-Cut Flanges - Flanges are precision cut from thick 3/8" 304 stainless stock to retain shape, with voids for weight reduction.
- Mandrel-Bent Tubing - One-piece tubes are solid-formed instead of pieced together for smoother exhaust gas flow and long-term durability.
- Band-clamp attachment maximizes underbody clearance and makes exhaust removal and installation quick and easy.
- Full 304 Stainless Steel construction for heat retention, durability, and corrosion resistance.
Full lifetime warranty against defects in materials and craftsmanship.
Fits all left-hand drive E9X M3 cars - does not fit RHD models.
Made in USA
Notice of Emissions Non-Compliance. Removing, disabling, or altering emissions equipment on a pollution-controlled road vehicle is illegal. Installing devices or software that trick, disable, or modify emissions controls and monitors on a pollution-controlled road vehicle is also illegal. This product is sold only for racing, competition, track, hobby, or other off-road use. It's use is prohibited in any motor vehicle that is subject to emissions inspection or control. Legal only for racing vehicles that may never be used, or registered or licensed for use, upon a public highway.
