These are the properly modified M52/S52 steel tubular headers as required by the Spec E46 racing class rules.
They are carefully checked for any defects or cracks before undergoing modification for use on the M54B30 engine. To ensure clean welds, each header is completely media blasted. Then the secondary air ports are TIG welded with stainless steel filler to completely close them off so no leaks can occur. Additional welds are made in strategic spots to prevent cracking and leaks, which may occur due to track/race abuse. The mating surfaces are machined flat for optimal seal using stock gaskets (either S52, M52 or M54 may be used.) We also offer a header installation kit for your convenience. Any additional repairs are also made to ensure a solid set of exhaust manifolds. Finally the headers receive one last trip through the blast cabinet to remove any last remnants of debris or grime.
Note: whenever possible we attempt to use the stock original studs, unfortunately these are a known weak item when rust or other debris set it. If the stock studs are irreparable, an aftermarket solution must be used instead as the studs are not available from BMW. A simple nut and bolt will suffice. We recommend using an exhaust lock nut (no nylon) and high-temp copper anti-seize to ensure ease of future maintenance.
**There is no guarantee that all the original studs will be in place. Any questionable studs will be removed automatically during modification. Please check the option above if you want absolutely no studs to remain. If you wish to have factory studs in place, you can request this in your order notes, but this may delay your order until we have a serviceable pair in stock.
Requires the complete Spec E46 exhaust system to install in the E46 (or custom setup). Direct replacement in the E36 328i and M3.
NOTE: These exhaust manifolds are strictly for off-road use on race or track-only cars. It shall not be used in vehicles driven on public streets. Proof of installation on a Race/Track-Only application may be required. We will not provide any support for use of this part in a street-car application and doing so will void any warranty.
Modified in the USA!