This is news to me! From Racingbeats website as of 12/16/02 www.racingbeat.com

1986-92 RX-7 (Non-turbo) Streetable Header/Collector*
Our Streetable Header/Collector is designed for a bolt-on installation, when used with the appropriate Power Pulse Presilencer, in all 1986-92 non-turbo RX-7s. The combination of this Header/Collector and the appropriate presilencer replaces the stock exhaust manifold and all catalytic converters, along with any intermediate pieces of tubing. (In this application, the presilencer will bolt-up to the factory Y-pipe.)
For optimum performance gains for this application, we recommend that a header be used on an engine configured with a carburetor intake system. For this reason, we suggest another suitable configuration for use on a fuel-injected engine is the Racing Beat Catalytic Converter Replacement Pipe with Presilencer combo. These components offer comparable performance gains, quieter performance and a price advantage as compared with the header/presilencer combination. These components replace only the stock exhaust components located between the stock exhaust manifold and the Y-pipe. The Header/Collector assembly is constructed with .125-inch wall, mandrel-bend, mild steel tubing for increased durability. Both flanges are flame-cut from .4375-inch thick steel plate for positive gas sealing. An outlet gasket is included. Engine-to-header gaskets are available separately (See Gasket section).
*Legal in California only for racing vehicles, which may never be used upon a highway.

 

Ummm...what's changed, I remember it always being like that?

 

From what I know; "OPTIMUM" performance would be the header and a stand-alone.

 

I believe the reason they say use a carb is due to the restrictive stock FI. But if you did go stand alone (got rid of the MAF) did a little porting to the intake manifold I think life would be good

 

I thought they always said that? From what I remember it's been that way...heck maybe not.

 

It's always said that

 

But they don't sell standalones, so therefore their modified Holley setup would be much better.