Im putting Pacesetter longtubes on my car, and I just need to clarify something. I will see no gain using true duals over a 3" catback (such as hooker) because my motor has stock internals. Is this correct? What about an X-pipe and true duals? Would the only difference between the two be the sound?


Rob

 

your going to get a million different responces from everyone. Theres always going to be people for them and people against them.

Lets put it this way, your not going to lose power, and it is going to sound awsome.

If your interested, i have a 3 inch h pipe dual exhaust (dumped before axle) that i'm not using. It will be a direct bolt up to the pacesetters.

 

there was a article just done where they tested a tru dual 3'' x pipe system compared to the mufflex 4'' cat back and there was no gain with the tru duals over the cat back... just something to think about

 

thats an above average catback tho

duals will allow for future growth and it sounds awesome

 

yeah a 4" catback is comparable to 3" duals (read that somewhere)
a 3.5" catback is comparable to 2.5" duals

 

i only see a few hp when the motor is being reved out using tru duals, because im sure duals flow better than just one 3 inch pipe...thatsa given. Now Longtubes,X pipe and Bullet mufflers just sounds Mean as hell at full throttle!!!! i know cause "narlydude" just got done putting his on and it sounds raw! but at idle, my Borla is louder than his tru duals.
Its all about what you wanna do

 

I don't know about the hp gain b/c my car had a bad exhaust leak before and I haven't had it dynoed. But just for the sound alone....wow. I was smileing like a little kid at christmass for the first couple of days. After 1/2 an hour or so of driving it my checks started to hurt.
-brandon

 

This is not directly related, but it's information to use any way you see fit.
I made back to back dyno runs with the difference being a 3" cat back with
a Flowmaster 80 series muffler compared to a 2.5" true dual system with
Flowmaster race series mufflers. The true dual system was over the axle
and there were no other modificaitons made between the runs.

The car is a 97 with dual factory cats for the first run and dual magnaflow cats
for the second run. The true dual made 12 rwhp and 8 rwtq (STD) over the
3" cat back system. This is with stock cast iron manifolds.

 

Just a thought...

It is entirely possible that the increased xsectional surface area of two mufflers vs a single is the reason for the increase. It would be nice to see the results of two mufflers spilt at the rear from the 3inch exhaust. Think of the mufflers as resistors. Putting them in parallel should make a nice little difference

 

So in other words I would only see a little gain (< 10 horse) with true duals? Im starting to lean towards a hooker catback.... hmmmmm.. I dunno

 

You're going to have MAJOR ground clearance issues with true duals. I've seen F-Bodys [mostly 3rdgens] running true duals, and they have like 1-2" of ground clearance from their pipes/mufflers.

 

I've run both on my car, so here is my opinion . . . no dyno or track numbers to back up the comparison. When my car had stock internals and bolt-ons I was running a 3" ATR catback and Mac mids with ORP. That was good enough to run 12.8's at 107 with a stock stall A4. It was also loud enough to enjoy, but not too loud that I would get tired of hearing it on a long drive.

Now I have a 383 SR with Jet Hot LT's, 3" x-pipe, 24" bullet mufflers and dumps with a TH400. It does sound like a freaking beast, but with compromises. Good luck having an intelligible conversation with a passenger, or on a cell phone . . . and the radio needs to be at the 1/2 way point to really hear the music. The darn thing will set off car alarms at 1500 rpm's in 3rd cruising through my neighborhood. I think that it's only a matter of time until I get an "excessive exhaust" citation

My opinion is to do the LT's, custom Y-pipe and cat-back. That will be a good match to your current combo and give you room to grow with mods.

Good luck.
Pete

 

really? i run 3" duals with no problems at all.

then again, i have them ran over the axle and out the back. if you do this, its no different than running a catback out the back.

 

yeah, i also run true duals 2.5" all the way out the back and over the axle in place of the stock exhuast (theres a pic of it on my site) but i didnt loose any ground clearance.. though i think i lost the ability to lower it because of how low one of the pipes is going over the axle... if it sat any lower itld smash the pipe =/ gotta run one out to the other side if i ever decide to lower lol.

 

I think im gonna just go with a catback for now. I dont plan on modding the internals of my engine quite yet... Thanks for the help everyone..


Rob