Is something like that even worth a tenth?

 

On the street and for local events I'm running a mazdaspeed v2 exhaust (dual muffler) which is ~6-7lbs lighter than stock. I've had it installed on my car for ~1 month and it's sounds awesome.

I've assembled the parts for my Solo Nats exhaust which I *might* not be able to run at local/regional sites with strict sound limits. All the pieces in this exhaust come to 7.5lbs - it's basically a turn down with no muffler.

As someone mentioned earlier, the biggest gains will come from reducing unsprung weight and I'll be running Miatamoto's former gold OZ ultraleggeras.

 

Always good to have another excuse!

 

I put a Magnaflow-based system on an MR2 Spyder once, and it was perfect. Nice and quiet around town, just the little bit of throaty you want. When you were on it for awhile, like driving up a mountain, the packing would heat up and not be as effective at absorbing energy. It would get the perfect amount louder. Self-tuning to the way you're driving.

As for "does the weight really matter?" Most single advantages don't by themselves make the difference. An advantage in racing is the accumulation of many small differences. Possibly very small. Winning by a little is better than losing by a little.

 

Does it make a difference, had to say for sure, and even harder to prove. On the other hand you have guys that will relocate their battery to the right side of the trunk, even at the cost of adding 5 lbs worth of wire to get it back there.

My muffler, just the muffler not the rest of the pipe, is 8 lbs. Given the choice I am going to put that 8 lbs on the corner of the car that is light, keeping in mind a stock class RX-8 has no provisions for corner weighting. If I am going to carry the weight around I want it where it can do the most good, or the least amount of harm.

 

...excellent observation I read a story that went omething like this, not sure where.

The budding racer was frustrated. He was looking for "the secret" as to how to improve his time and beat his rivals. After a lengthy discussion from his instructor about all the things he might do, the plan was to eak out at most 1/10 of a second improvement every corner. So the racer asked, "Is it really worth all that trouble? ... I mean....just to go 1/10 of a second faster each corner? Well, the instructor said "By the end of a this 10 corner per lap, 10 lap "race" you could be 10 sec ahead of the guy you're running with now, if only you could save that 1/10 sec per corner...

 

Spend $7 @ AutoZone for a turn down and your exhaust is done. Low hanging fruit.

 

If you try to run that $7 exhaust at the SD Tour, it might end up costing you quite a bit more, in terms of gas, lodging, tires etc....once you get DQ'ed for sound

 

Did you take off the RB exhaust to install a DIY muffler? Why? Weight? Noise? Look?

I just put on the RB exhaust and was suprised by how loud it is.....It seems to have settled down some since I first put it on but there's no doubt you can hear me coming....

 

I've had the RB race exhaust for about 9 months now. I agree it's a bit too loud for daily driving. Under load (like going up a hill) the drone is pretty unbearable. I'm thinking of going DIY now... the 16" Borla is a bit quieter, lighter, and I can reuse some pipe from the stock system I still have lying around.

 

Last time I talked to Thomas, he was ditching the RB because of the noise. He drove my car (with an "Isley home special" exhaust), and decided that it was a lot quieter inside the car, and sounded better from the outside.

I drove his car around the block with the RB Race exhaust on, and I couldn't believe how loud it was inside the car. I couldn't imagine living with that exhaust on a daily driver, and I've got a pretty decent tolerance for loud cars.

 

if you dump it anywhere except out as far back behind the bumper as possible it will sound a lot louder inside the car than out

so you might consider having someone cut the turndown off and pipe the RB outlet out of the exhaust shroud rather than ditch it

the further out you extend it the better for reducing noise inside the car, even for a straight pipe (which again won't pass at SD or other sound-lite sites without some sort of diffuser)

 

I had Doug Chase do something similar to the Isley exhaust (same thing Joe Goeke has), which is basically cutting off the main center pipe right before the OEM muffler, welding a small borla muffler on in place, and exiting at the passenger exhaust spot, same spot as stock (with nothing on the driver's side exhaust hole.) It's definitely a little droney cruising up hills/80mph highway cruising, but it doesn't bother me, and it sounds great at autocrosses.

 

btw the tanabe ultra medallion weighs 20lbs

 

I think the Racing Beat exhaust is a really nice piece but I built the new exhaust for a good bit less money, it's lighter and it's quieter inside.

Team is right, turn down exhausts that terminate under the car are louder inside than out. I've had a couple of different cars with turn downs and when you hear somebody else drive them, they are a lot quieter than you think.

 

Yes. So you build 2 exhausts, one for SD, one for almost every where else. And an under car turn down on an Rx8 definitely sucks when you're too lazy too change it for the drive to work on monday...

 

I really love the look of the turn down and the build quality of the RB exhaust is top notch. We'll see how long I can live with the noise....Running a tip out the back may be a good alternative but then I lose the stealthy nature of the RB exhaust.

 

Here's a look my Isley/Racing Beat inspired custom exhaust. Magnaflow with a turndown in the far right corner. The sound is ok on my 25 mile commute but drones pretty heavily when towing the trailer. I have a quick change clamp/flange on both the OE and custom exhaust. Takes about 10 minutes to swap them.

http://www.youtube.com/watch?v=aQkBKdVM7WU

Chris H

 

I suppose an honarable mention should go to the Corksport exhaust. If you have to have two exhaust tips, and can't afford the Ti stuff, then the Corksport will save you about 15 lbs at a decent price.

The sound is fantastic, especially with the windows down - like a big-bore superbike. I get lots of compliments from fellow autocrossers and my car buddies at the office, and even people on the street. It is loud, however. In fact, with the windows up, it turns an empty trunk into a resonance chamber at freeway speeds - not good. I was thinking of going to a Isley-style setup as a result but I found that if I threw a couple of small synthetic blankets in the trunk it was enough to kill the resonance, so I'm going to keep it - the sound with the windows down is plenty worth the small hassle of having to kill the resonance. And yes, I take the blankets out when I autocross.

 

GeorgeH - you can solve the 3K rpm resonance problem w/a bit of deadening material on the floor or the trunk and have 'the best of the Corksport', great sound when you want it, no resonance when you don't. I did the floor and sides of the trunk and the top side of the over-muffler' shield underneath w/aluminized duct dampening material and all is quiet - except just roll down the windows when you want to hear that great ripppppp sound!

 

https://www.rx8club.com/showthread.p...22#post2331722

 

finished, pics posted in the link above, easily meets the strictest sound dB specs despite full flow capability

 

Nice work, Mark...umm, Team...

 

corksport: 24 lbs lighter than stock

 

the OE exhaust is 39 lbs

There's no way a CorkSport exhaust is 15 lbs