Best Exhuast system for milage & performance
 

I've got an 84 GSL and I believe that next year or the year after it will know long require EPA equipment. I'm wondering what the best modifications would be for improved milage and performance. Who has the best exhaust system out there?


Greg

Your first problem is that you're looking for mileage out of an RX-7.

Second, what kind of exhaust system are you looking for? Loud? Quiet? What's your budget? Are you looking for a bolt-on solution or can you go all custom? Racing Beat makes two fine bolt-on systems for our cars that aren't very loud, but they come with a significant price tag and don't flow like a straight-through system would.

And last but not least, SEARCH NOOB!!!1!1 :)

My first gen got the best average power and mileage out of the Racing Beat streetport system. It may not be the lightest on the market and may not be the cheapest but it is rock solid and sounds quite nice. Not overly loud like 99.9% of the aftermarket systems out there but loud enough to be noticable. I liked it.

My 2nd gen got the best mileage with a true dual exhaust setup. The lightweight flywheel actually helped that car too. I averaged 20-21 in the city and the high 20's on the highway in that car. The 1st gen would be a little harder to make a true dual setup for and still get muffled decently. Then you have the matter of the horrible sound of a true dual. Sounds like a 1 rotor crossbred with a lawnmower. Horrid. That was the only downside but it performed nicely. If you need to stay simple and easy, the Racing Beat system is real hard to beat (or match for that matter).

Still Looking at Exhaust
 

Oh Great Rotary God:

Thank you, I looked at Racing Beats site this morning. That does look like the way to go. I'd like to keep it sounding fairly civilized.

I've got a year to go here in Georgia before they no longer require the emissions testing, so I’ve got some time to decide.

One of my old mechanics says he can install a high flow system like that that will still meet emissions. I find that very hard to believe. Perhaps he knows someone he can pay off. I do not.

I had headers, a venturie block, and light flywheel on my 79. Big increase in performance but not much help on mileage. Perhaps it was just my lead foot. I was much younger then. Damn, I wish I still had that car!

Would a light weight flywheel help a car with an automatic? Believe it or not the automatic does alright and in Atlanta traffic. Besides they would have had to amputate my leg by now if I still had a shifter.

Technically speaking you don't have a flywheel with an automatic. Just a light ring gear that the starter engages to. There is nothing there to replace.

One of the things that makes the Racing Beat system work so well is the system design in regards to where the pipe collect. They join at the rear of the car just before the muffler. This is called a long primary system and is my personal favorite configuration for all around performance. If you are trying to stay emission legal, you'll need a cat. If you are trying to stay legal with a long primary, you'll need 2 of them. One for each pipe. Then you'll have to figure out a way to get the air pump pipe to each cat as you can't pass emissions without an airpump (on gasoline). You can use a highflow cat with a more conventional header setup and it will still be better than the stock setup but the shorter collected length will mean less overall power throughout the powerband. There's always a tradeoff. You aren't going to get it to perform just as good and still be emissions legal.

Weight is my only complaint (and price but you get what you pay for) with the Racing Beat system but saying that, it isn't any heavier than the stock system. I weighed them both once but I don't remember what the numbers were. It's just not considerably lighter than stock as many others are. You'll like it. Everyone I've ever seen that's had it has loved it. The one's that typically recommend against it are also usually the people that have never owned it. Go figure.