So I've been reading up on what mods should be done to my RX7, and I am now looking at getting a better flowing exhaust on my FC. It has a single outlet Magnaflow cat back installed, and I've read good things about their stuff here on NoPistons. The next logical step seemed to get some headers; however, from what I've read, there are some trade-offs with this.



The one that concerns me most is the operation of the 5th and 6th ports. My understanding is that if you wire them open then your low end loses some power (and the motor already isn't much of a powerhouse down low) or ditch them completely and the top end suffers. Obviously power loss is bad, so the other alternative is to get an exhaust system that retains their operation. The choices for that seem limited, i.e. Racing Beat. From what I can see the other brands (Corksport, OBX, Pacesetter, etc.) don't have the exhaust backpressure hookup to operate the ports. Is Racing Beat the only option if I want to keep the 6 port setup, or are there other brands that I've missed?



Also, the general consensus seems to be that headers are super loud. I don't really want to sound like I'm driving a 747, I like loud, but not super-Godly-wake-the-dead loud. Is the downpipe/presilencer kit from Racing Beat a quieter alternative to a header, and will that allow me to keep the 6 port setup?



On top of all this, with a header and catback setup, is there any prayer of passing emissions?

 

Catbacks dont matter as long as you have your required emissions stuff and im sure cs works you can always ask them if it works with the na 6 port engines seeing as they have been around for awhile rb is expensive if you go with them

 

any header you find can be made to work with the 6 ports. all youll need on any of the others is to weld on a hookup for the split air tube. that said for header options RB while expensive has the best quality and a damn good design, you really cant beat it. Pacesetter is garbage if you do buy one expect to be replacing it frequently, the heat of the rotary kills their cheap pipes. Corksport is about the only other option i would go with besides the rb.

 

If you dont wanna deal with buying all the pieces buy a corksport one

 

This is my settup for a 1991 NA. I run with a Racing Beat Road Race Header, preslencer, Y-ppe, and extension tubes that connect to my old Borla mufflers. The difference from stock is dramatic. If you live in CA, or another state with strict emissions laws, save your stock exhaust manifold and down pipe for when you need them. The RB Road Race header has an O2 bung and internals that activate the 6th port at about 5500 rpm. Unless you are wide open on the track under strain, sound is usually below 95 db.



Regards, '

Jeff

 

Thanks for all the feedback. I suppose I will have to save for a few months and go with Racing Beat or Corksport. Mind as well do it right the first time, and hang on to the factory pieces just in case. I don't really know how strict Texas emissions laws are, so I have some homework to do. Regardless I'm looking forward to getting them...perhaps I'll have a little fire breather now.

 

Dallas ft worth does emissions testing, but if you move two hours north to Wichita falls then it's just a safety inspection, no sniffer. Emissions laws vary by county, but in any of them you can find a tech that does inspections and will run the sniffer on another car but run the ticket as yours for a little extra cash. What part of dfw are you in?

 

I'm in Flower Mound, which is about 45 minutes from the actual Dallas/Ft. Worth metro. I'm in Denton county, and they are one of the like...10... that test emissions in TX. I was kinda sad when I saw the emissions testing map on the DPS website.



I suppose I need to find the "right people."