ritz

iTrader: (1)

Ok I know this topic has been beaten to death, drug through the dirt, shot at, killed and brought back to life, but I'd like a fresh set of opinions.

My dilemma is this. I have LT's with TSP TD's. I absolutely love the sound and love how it feels according to the ole' seat dyno. Right now I drive a company car so I'm not cranking up this car early in the morning, but soon I will have another job and will be driving my car and cranking that car up that early is a big NO NO.

Here's my question. I went straight from stock mani's, y pipe, and catback to Pacesetter LT's, no cats, and TD's. It was a wonderful feeling, but I've heard that the TD's make a big difference in the HP and TQ curve. My question is this. Will I be disappointed when I replace it with a 3" ORY and say SLP2OTL or Hooker catback?

I'd like unbias opinions please. I don't want TD owners coming here saying "OMG TD's r0X0rS and CATbacKs SUCK1!!1"

Thanks in advance.

JustAnIlluzion

iTrader: (60)

i have searched that question, and its been proven duals out perform a ypipe setup. so its up to u to lose some hp for a quieter car. i too just went from stock to pacesetters and soon to be 3in duals. i gtg have that muscle car sound and might **** off my nieghbors but its worth it maybe u can add some hi flo cats .. or go to a shop and have them extended out to the back.

cyphur

iTrader: (10)

A well designed y-pipe setup can perform just as well as a true dual setup, if you know how to set it up. While it is true, that the scavanging effect of the x pipe is generally lost, that doesn't mean that all the performance is lost. You can still design a y-pipe based system to perform just as well. Hopefully someone who is a little more knowledgable on the topic than myself will chime in here, but I do know that it can be done.

blkZ28spt

Duals outperform a Y-pipe, it's a fact. However there are plenty of people who run VERY well with the standard Y-pipe setup.

I suggest a muffler swap. Try some Borla XR-1's, add high flow cats or the larger magnaflows. (forget which ones they are, exactly...maybe 4x9's?)

I just deal with starting mine up everyday/night whenever I go somewhere, plus the large cam. Or shoud I say the rest of the apt complex deals with it, but no complaints and I've been here a year.

Time2Kill

iTrader: (49)

I'd try quieter mufflers and/or adding a pair of hi flow carsound cats.

300bhp/ton

ok I'll be as honest as I can. So far there is a lot of MIS INFORMATION being posted on this thread.

A good dual setup can out perform a moderate or poor Y setup, but that doesn't mean its the duals making the difference its all the other factors. Many people go from totally stock exhaust to new headers, large bore tubing, cat removal and free flowing silencers - 2 of them, where as stock would be more equiverlent to running 4 silencers. This of course makes more power so they proclaim duals are better than a Y pipe.

A well designed Y pipe is as likely to produce the same power as a well designed X pipe.

Many racing/rally cars run Y pipes into a single outlet - Corvettes C5R and the C6R, in fact most V engined race cars (non drag, circuit) will use a Y pipe setup, this is because the can and DOES produce the same numbers as duals yet also save weight and space.

Back to your question however.

IMO the easiest way to quiet it down is to change the silencers, there is very little reason that duals should be louder than a Y pipe. Also if you pick your silencers carefully you should loose next to and maybe even nothing in power, but it will reduce the noise. (check out the sticky about exhausts, you may find it helpful).

Remember lots of other cars run duals as either stock or after market. You can have a C5 Corvette with a performance exhaust that is still socially eceptable - it has duals.

Redneck Z

iTrader: (3)

I don't know....all the comparison dyno's I've seen show a dual setup making better power under the curve and slightly more peak power. Not that a y-pipe setup can't make great power, but the dual setup seems to be superior. It's also pretty unanimous they make more noise than a y-pipe setup.

greatskiiiier

iTrader: (10)

start the car up everyday before you go to work the next week or so and see if there are complaints, if so, buy the borla XR-1's and do the same, by the time you have the new job you'll know what your neighbors are happy with, and what they'll call the cops on you for

300bhp/ton

yep that sounds correct, becuase most of the Y pipe setups out there are not that great but mearly better than stock, so the duals do then to produce more under these circumstances.

As for noise, I've never actually tested it. But I do know lots of cars have duals and excessive noise is not an issue. In additon a lot of the cat backs for a Y setup often use a single large liencer, rather than with duals two small liencers.

300bhp/ton

From an expert:

blkZ28spt

Duals make more power than a y-pipe, mostly under the curve.

Difference may not be huge, peak numbers should be fairly close, you don't need duals to haul ***, etc, but they do make more power.

magius231

iTrader: (8)

read the exhaust sticky, and pay particular attention to the David Vizard clip about Exhaust Science. You CAN have a zero loss Y-pipe system, but it requires a bigger diameter pipe than most cat backs will give you. At 370 FWHP (thats flywheel for you noobs ) you need to step up to 3.5" pipe, and at ~500HP you need to step up to 4" pipe. You need 2.2CFM per motor HP, so at your typical bolt on/small cam car making 400HP at the motor, your single muffler needs to flow 880CFM and I'm not sure how many can claim that at 3.5 inlet. This is why duals seem better to most people, you can run two mufflers and the flow requirements are split, so a muffler that may not perform so well to begin with gets a boost because theres 2 of them (why do you think they went factory true duals on most old muscle cars? ) You folks with dual 3" with an X-pipe, hope your making over 500FWHP because otherwise your not making the power you could be because your scavenging is going to hell. Dual 3" is good for over 800FWHP.

As far as weight savings, true duals with bullet mufflers and dumps probably weighs a whole lot less than a Y-pipe, 3.5" I-pipe going all the way back into a crossflow muffler, then 2 tailpipes. Want the ultimate Y-pipe setup? Stick a 3.5" or 4" high flow muffler on the end of your matching Y-pipe and just dump it from there. Loud? oh yeah.

blkZ28spt

The reason duals are capable of making more power isn't necessarily "zero loss" due to all of the flow capacity, but exhaust scavenging.

Besides, duals just sound so much better.

ritz

iTrader: (1)

Thanks a lot everyone for your input. It's very much appreciated.

777

iTrader: (21)

If you want the quiter get different mufflers. Put in some cats and extend them out the back. The edelbrock 304ss mufflers are pretty quiet. Here's a clip. kooks lts, 304ss mufflers, dumped, no cats

http://ls1sounds.com/true_duals/TDs_...f-drivebys.mpg

josh99ta

iTrader: (1)

ritz, WTF r U talkin bout, OMG TD's r0X0rS and CATbacKs SUCK1!!1

Get a good y-pipe, get the Flowmaster merge, put a cutout in the I-pipe of whichever catback you go with, and get a quiet catback. You'll lose a little but plenty of people have went fast with a y-pipe setup. The smarter thing to do might be to change mufflers and add some high flow cats to quiet the duals down some, and that is what I'd do if I was ever worried about it, but if you really want to go to a y-pipe setup it wont be a big deal.

300bhp/ton

Well according to a chap I've spoken to at Maganflow he beleived a well setup Y pipe would flow and have the similar scavenging characteristics as an X pipe.

That is good info there. And I run a similar setup on my V8 TR7, compition spec Lt headers into a hi flow Y pipe into a single silencer with a single 3" outlet. Exactly the same as the British Layland Works Rally Cars had, and it is far louder than the duals on my V12 XJS Jaguar.

josh99ta

iTrader: (1)

ritz, this setup is seriously as quiet as it's going to get. That sounds just like a long tube/y-pipe/quiet catback system, but its got a better tone to it (TDs). Before you go out and spend $500 on a y-pipe and catback I'd look into slapping a pair of those mufflers on.

Seriously man, bullets are a no-go IMO. You dont know how bad they sound until you hear a TD setup with some better mufflers on there. I'd save some money and try some 304ss mufflers or some of the Magnaflow 4x9s.

DJ's Z

iTrader: (10)

I know for a fact a good y-pipe set up works!! 3" Y to Flowmaster 3.5" collector to 3.5" I pipe/3.5" cutout for those "fun" runs/single 3.5" into Spintech dual 3" out...works for me and sound great!

blkZ28spt

I definately wouldn't say that bullets sound bad. There are better (and more $$) muffler choices out there, sure, but the majority of people with duals run bullets. That is what came with LS1 Speed's dumped duals and TSP's Rumbler X, for example.