So ordered the parts yesterday and going to see how quiet this badboy can get and how loud it can get on wot.

3 inch stainless steel downpipe
Rx7store mp - modified with an apexi ECV
Racing beat cb DT

I'll let you guys know well it cuts out the droning

 

i have a 3in DP and a version 1 RB dual tip. its QUIET. its quieter than my OEM with rust holes.

 

I'm starting to think all you guys do is whine about your exhaust being loud, it's a rotary mannnnnnnnnggggg. Leave the stock exhaust on then

 

Moar powa! And less noise is so key now a days...


Esp with the popo going nuts here on long Island.

 

I love florida my exhaust can be as loud as I want! Any recommendations on loud exhaust?

 

Thats cause Florida is full of old people and they are deaf anyway!

 

my plan is to go withna Trust 80mm DP and then splitting up to double 60mm piping through a double 60mm mid silencer running double piping all the way to the back (same setup for tha catback). End tip can still be a single (flat oval) or a double tip.

Key to exhaust tone (or how loud it is) is the frequency of the resonance wave in the exhaust plumbing. The bigger the diameter, the bigger the resonance wave, the louder the exhaust is. People want bigger for more flow.
I'll try and solve that with double 60mm's, flowing more than an single 80mm. Small diameter for a small resonance wave and deep tone.

Still, good luck with your project

 

That was my rationale as well. I couldn't find that other wise I would have went with the knightsports dp. I'm hoping that the apexi's valve/flap will obsorb alot of the wave travel even wide open.

I ordered the 80mm ~ http://cgi.ebay.com/ebaymotors/Apexi...spagenameZWD1V

Btw ~ I made an offer for 140 an was accepted so it was 155 total if anyone is interested

 

If you don't want to use a cat, use a mufflered / resonated mid pipe. They can be had pretty cheap and are proven to work.

 

Thats what the Rx7store mp is...

 

I have 3" down pipe, an emptied high flow cat, and a RAcing Beat dual tip on a pretty large street ported motor. It is not loud, you can certainly hear it even at cruise but no droning and not annoying at all. It still can get very noisy at full throttle and thats what really matters!

 

i have a 3"dp, mp, and rb catback...

its pretty loud. but i love it

 

Yea, I only want to hear it at wot. I have 3 main noise killers in my car.

26lbs of sounds deafening (Q-mat) all on the rear and hatch.
Rx7store MP - custom Apexi 80 mm ECV
Racing beat dual tip

I'm having the ECV put all the way up in the furthest part of the mp so I don't hear the sound reverberate through the cars chassis.

 

actually the rx7 store has straight through midpipes not just resonated ones.

 

Oh, Well I ordered the resonated so it should be pretty quiet.

 

^^ BTW good choice. That's what I had and I loved it. Nice deep tone at idle and med throttle, and loud at WOT. The best thing was that almost zero drone at highway speeds.

 

Just what I'm lookin for!

 

Question for you guys, does a resonated midpipe work to keep the odor down? I know midpipes make the car smell like gas but does having the resonator help out?

 

^^ nope. The exhaust gasses are still going straight through.

 

I guess its a high performance or gutted cat for me then. Thanks alot montego for the quick answer.

 

I found my unresonated midpipe to be quieter than my resonated one especially RE: highway DROOOOOOOONE.

maybe I'm an outlier though

 

Either way if I sense droning on the highway = click an the valve snaps shut or 95% if need be.

You only need 18hp to maintain a speed of 60mph in an average weight/not so aerodynamic car, judging by that I'd say the FD can keep pace fine even with that restriction

 

point is that at 3 or 3,5 (or 4 if it matters) is just to big of a bore to have a a short resonanting wave. So it will either be loud or very loud, but not what you want.

I had what you are refferint with a HKS downpipe, oem cat and home made catback with 70mm piping and muffler with 70mm throughout piping.

Replacing the oem cat will put you right in the 'loud' group... no matter what.

 

The only thing I would worry about is how all that restriction will effect the tuning. Will you just tune it with the valve open? If you go wot with the valve closed will it be really rich?

 

A gutted stock cat will smell bad too. Of course, the price is right.