Ok boys and girls I have "put up" with the smell and the noise for 7 years and currently running a 3" staight through d/p m/p and Greddy sp with a 35 r single and would like to get some civility back.
The goal is to quieten things down AND reduce the smell,what are my options?

I have read the old threads that talk about reducing the noise only people seem to like the Rx7 midpipe and a Racing beat duals,options please

 

I run a midpipe with a Magnaflow welded in and a RB dual cat-back...definitly sounds great at idle and WOT. Now with the smell issue, I'm planning on having a metal cat welded in, but something along the lines of 100cpi (don't want to lose too much power).

Btw, I also have N1 duals and other midpipes that I use, so I know where you're coming from... with my current "civilized" set-up, it is a huge difference.

 

Get a hi flow cat and Rb duals. I guess after a while you get tired of the noise eh. I have a hi flow cat with the Apexi GT spec and some days I hate hearing the damn noise

 

I am about to go this route...fixing noise and smell myself... I have DP/MP/HKS carbon ti. I am definately going with the racing beat dual tip, and getting a metal substrate cat as well..

 

What's the highest flowing universal cat available?

 

How about the FLOWMONSTER

http://cgi.ebay.com/ebaymotors/41030...QQcmdZViewItem

 

Best... and what will get the job done are two different options... Best SMB Metalic cat with muffler midpipe and SMB daul tip exhaust... get the job done high flow cat..silencer..RB duals... Just my opinion.

Chris

 

I have a Carsound hiflow cat that I used to have in the car. I'm planning to put it back in. Since I'm running single turbo now without the airpump, I take it that I just need to plug the air pipe that runs into the cat? Or can I just leave it open to atmosphere??

 

If you have a good stock main cat they flow as good or better as any aftermarket HF ceramic cat even with the 2.5" pipes. Even better than metal if you replace the I/O with 3" pipe. This is based on actual flow bench tests.

Just plug it. *You CA guys will need the airpump working to pass smog.*

 

Disagree.

The stock cat was designed in the year 1992. Technology and materials have improved flow and catalysis since then. I don't believe "tests" since they're biased by the manufacturer(s) and seldom held under equal (fair) conditions. It's too easy and too often the practice - especially when it comes to "tuners" - to doctor results in the name of marketing and selling their periodicals and the products from the manufacturers that sponsor those periodicals. And people wonder why they don't get the results that they read in a "test" or a tuner magazine.

I own a stock cat/stock piping (actually a new Magnaflow welded where the stock cat used to be), and I own a high flow. There is a HUGE difference in flow, and it's a difference that you feel when driving. My high flow cat's piping is mandrel-bent, and the internal diameter of the high flow is substantially larger than the stock piping, to say the VERY least.

Here's a pic of my high-flow, aside from the fact that it's 30 lbs lighter than the stock catalytic converter:


I agree with Chris that the RB duals are good for flow without being too loud.

Furthermore, platinum, rhodium and palladium are the *metals* traditionally utilized for hydrogen catalysis.

That's just the Med student in me talking. Just so we get our information straight

 

will that thing last on an FD ???

last time i used a magnaflow cat .. it lasted 1 day ...
it was this model here


i was running ~ 12-13 psi on stock twins with petit unlimited .

what part number is that

 

What the stock midcat is great for controlling boost creep not increasing it. No need for bench test the proof is in the pudding.

That said the stock midcat is not only great for controlling boost but it's a well made exhaust piece that's great for controlling sound and with the airpump hooked up smell as well.

 

So Fritz, are you saying that the only benefit I would get from installing my hiflow cat versus resonated midpipe, is a decrease in sound? Wouldn't the smell decrease as well with or without an airpump connected? I'm a little confused??

 

the smell will decrease with any cat and without an air pump ... it wont smell like a scooter anymore

 

I'm not familiar with the 'Carsound' hi-flow cat, but when I deleted emissions on my car I pinched a short section of the metal pipe that was attacted to the air inlet on my Bonez via a section of rubber line. That way I didn't have to pinch/plug the actually metal inlet on the cat. And my Bonez seems to be unaffected by the loss of the air pump over the last two years.

I also agree that any decent hi-flow cat should decrease sound and smell.

 

My car smells like ***. I actually refused to drive it some days because I do not like my cloths smelling like I just road a chainsaw to work.

Are you saying if I REMOVE my air pump that my exhaust will smell better??

 

While I agree with you with respect to the reliability of published flow figures, allow me to clarify: I own a flow bench as part of my engineering business and I personally performed the flow tests on a number of different HF cats and other exhaust system components; so I can speak to accuracy of the results. (To that end, anyone is welcome to contact me if you have something you want flow tested.)

I can assure you that the flow of an intact stock main CAT is +/- a few percent of carsound, catco, etc.. based HF ceramic cats such as the one you picture. Metal cats do show an improvement in flow; however, if you put 3" pipes on the stock main cat, it will be even better than the metal ones. I reworked a stock cat to achieve more than 2x stock HF flow. It is quiet, and relatively cool externally (due to shielding) and it readily passed CA smog on my large ported motor.

Yes, it is heavy, but that's not all bad as the mass helps break up resonances in the exhaust system, plus it's low and in the center of the car. The stock-based cat does have more cross-sectional area & a more durable catalyst (due to a higher spec wash coat needed to meet manufacturers warranty requirements). The aftermarket units work OK for reduction/oxidation however they are designed to a shorter service life.

 

I just had a normal cheap magnaflow 3" cat welded in a 3" mid pipe. Didnt notice any loss in power compared to my other mid pipe with a 3" magnaflow resonator, running a 35r and streetport with rb dual's.

 

I heard these guys make the best highest flowing cats...

http://randomtechnology.com/

thewird

 

I think he's saying that if your air pump is removed you don't necessarily have to reinstall it.

If it's installed and you don't mind having it, hooking it back up to the cat will only help further.

Dave

 

Random Technology cats are really nice.

I've only seen them on supras, so I can't speak for rotary application.

For Sound:

What about heat wrapping the entire exhaust? (minus the flanges and muffler)

That would cut down on resonate noise coming through the pipe.

I have a brand new never mounted pre-cat, I plan on testing for flow, so if someone would be interested in doing some flow analysis of new OEM components (hint hint) I'd be glad to do what I can to have that data to the public.

For the gas smell:

tuning I imagine could probably be improved (with water injection, you can run leaner)

replace all carbon filters and recurculation features to the fuel system

air pump (either the OEM unit, or an electric)

perhaps switch to another type of fuel (E85)

 

i'll agree with the smb option. i have it with a peter farrell supercar 3" and it absolutely sounds amazing. Since i've had it on i've received numerous complements on the sound and tone from random people at stop lights. The best part about the exhaust combo though is that i can finally listen to music in my car instead of just hearing a loud exhaust drone.

The best combos to clean up sound imo would be - SMB + pfs or racing beat duals

 

Are you talking about the over all noise level of your car your sick of or just hearing your car loudly?

If your sick of hearing it, have you thought of that sound dampening spray? I know its a lot to do because you have to gut your car and spray it down but I hear good things about it... get it, "hear" good things... I know Im a dork....

 

It's counter to the trend of reducing weight, but I sprayed undercoating on the inside of the door skins and added commercial self-adhesive sound insulation to the spare tire well and hatch area. Proabably 25 lbs. total. Made a BIG difference in reducing drone, especially at highway speed...also with a Greddy SP. I can hear my stereo again and the doors shut with a nice solid "thunk" too.

And if the OP needs a reference for cats, I recommend Bonez. I've been running one for nearly 8 years (more than two years w/o airpump) and it still looks and performs great. No eye-watering smell like mid-pipes.

 

^ Your eyes only water if your running rich. With the a nice lean tune, it has a nice smell to it

thewird