Greddy or Borla???
 

Both cat-backs are about the same coin. I was told that the Borla doesn't flow as good as the Greddy or Billy Boat. It is like the stock exhaust design, while the Greddy and BB have a better, less-restrictive flow.

I know the Greddy makes 21 whp dyno'd with the midpipe. I figure the midpipe is 10 whp (just like the BB midpipe). So 11 whp for the Greddy, and the Borla. Which one to buy?



Troy Jeup

I just answered my question using the Search function. Yay! :)

well, don't leave us hanging. Which one did you choose ? :)

btw, 11 hp, for just exhaust ? My skepticism alarm just went off ... i hope its just misprogrammed

I would not buy the exhaust alone thinking you're going to get any noticable HP gains...

I think all the exhausts are gonna perform about the same. Just depends on what name you like and the asthetics. Flow through the exhaust regardless of which one you get is still gonna be restricted. Just look at whats in front of the exhaust and there's your culprit.

According to MazdaManiac... it won't matter because once you put n a mid-pipe or cat. the sound goes up... A LOT. Other the other hand perfomance does not... so in bang for the buck he recommends a mid-pipe only and new tips for your stock muffler.

I believe MazdaManiac has the mid-pipe w/o the resinator. Which in that case is almost too loud for street applications. If you do get the mid w/resonator it isn't that bad. I really don't even notice the increase volume that much.

Well, I got the high flow/temp cat with resonator, and with the Borla, it is a LOT louder - maybe 2 to 3 times louder than just the Borla. So much so that I got to where I couldn't stand it and took the high flow/temp cat/resonator off until I can find a quieter solution.

According to CZ -- The Greddy is VERY loud with the midpipe -- much louder than the Borla. My Borla with midpipe is borderline too loud as is (like Omicron mentioned) -- we are looking at a solution to reduce the sound level. My stage 1 solution is to install Dynamat in the trunk -- should have this in this week.

Hmm...I have the borla with the B&B midpipe w/resonator and don't find it obnoxiously load. Could the random tech cat change the pitch as such that it is rather annoying. Could you have burned through the cat?

One thingI likeabout the g35 and 350z is that even during lightacceleration you can hear the exhaust. I hope there is a way to dothe same w/the Rx8. Below 4000 RPM the stock exhaust of the Rx8 is basically onmute.

So, perhaps you'd like for me to take that hi flow cat w/ resonator out of your hands? Sent you PM.. hehehe

I had the B&B midpipe w/out the resonator on it. With the stock cat-back, it wasn't too loud. It just sounded like crap, almost like the exhaust was going bad. On full throttle, it is a little louder but you still can't hear it over the K/N intake. :) I think that my stock cat-back got messed in the process, it sounds like crap & you can see that it turned purple in the area where the heat comes in from the straight pipe.
The only con of the midpipe is that it will set your fire-detector off if you have one if your garage. It sort of smells like a snowmobile :( with the midpipe.

Troy