Ive got a set of Pacesetter LT's and a pair of 3" Sweet Thunders sitting in the house waiting for install. Im gonna try running without cats for a while but in talking to a speed shop nearby, they said they have set up a few f-bodys lately that run no H or X pipes, they just basically run your muffler off your header with a turndown to dump before the axle. There would be a small section of 3" pipe on either end of the muffler of course. Just wondering if anybody is running or knows of any actual #'s to prove if this setup actually is better flowing, the same, or worse than using an H or X pipe. It seems like everyone around here is scared of trying to install an H pipe which was my first choice, so its looking like Im gonna go X or straight out.

 

Run one or the other just to balance out the sound. You aren't going to get a clear answer on what's better because it's been asked a million times before and every other person has their own opinion. Just pick an X or an H and you can't go wrong.

 

Im going to run 3" duals into dumped 1 chambers next week with no mid pipe also. Going to try something different.

 

Im not so much trying to get info on the sound diference but whether or not the power #'s go up or down typically if you dont use an X or H pipe.

 

anybody done this??

 

From what I've read, true duals with a crossover pipe will produce more power because of the scavenging effect, which is when the crossover acts as a suction and pulls the air from each bank.

 

Ever heard two harley's racing each other?



Thats what it sounds like...Trust me.

 

ya i just put jet hot lt's with a 3" true dual dumped thru a 18" dynomax buillit and its louder than ****!!!!!! im not shure if i like it. it sounds badass dont get me wrong but its kinda redicoules.

 

I've done both X and straight back. This has come up alot lately, butI will tel you since you didn't hear my view. There have been a few magazines that have tested H vs X vs straight and it always shows the H gaining no more than 5 horses and X gaining about 3-4 more over the H vs straight pipe. So with the H expect 3-7 horses over straight pipe. I think guys on here always go with them because they want every ounce of power and like the sound. The H doesn't make as much because the gases must traverse the 90 degree bend, where as the X they can cross over much easier. The reason behind them geting more power is the fact that one bank of cylinder might have to much pressure so the gases can't escape as quickly, while on the opposite side of bank cylinders, there may be less gas pulses going on so basic physics always states high pressure always moves to low pressure. The gases will go across the X and lets them out quicker. There may be even a scavanging effect as well. Placement of the H or X is also improtant to et the most out of it because as the gases travel they cool down and this changes the dynamic as well-physics states that heat always moves to cold so the hot gases would want to naturally flow out. From what I remember to find the best place you mark the exhaust with crayon (might be the welders crayon) and you then do a few good runs and see where it discolored the most and that is the best place for the crossover. With our cars having a torque arm this can make things difficult since an X or H must go around this low hanging device which kills ground clearance. I had an H and X and eventually went to straight pipe because I was sick of scrapping on every speed bump. Without the X my exhaust was just ever so slightly louder and It had a ever so slightly different sound as compared to straight pipes back. I didn't lose anything at the track without the X because my times are never the same-at least 1-2 tenths off, so its hard to say how much power I lost, but I couldnt feel any difference be it 3 or 10 horses.
I'd say you'll be fine with just straight pipes, and I also had exit like pipes off the mufflers in the back. My exhaust stopped before the axle and it had a nice drone, so I tryed turndowns and it may have made it worse, so I made some curved side exit type pipes that stopped just before exiting out the side-about the same area where the LCAs are located and that made the biggest difference for sound, it stopped most of the drone and didn't affect the pure loudness of full throttle-so definetly do this mode on your setup, my pipes were only about a foot long going off to the side and it made a huge difference.

 

they make other flow through mufflers that are not as loud-I went with some thrush cherry bombs and it was much better than those bullets. They are heavier and longer, but it keeps the drone way down and its still way loud at full throtle.

 

Thanks for the input guys, and I like the idea of the foot long pipes exiting in the direction of the LCA's/ I may try that after I get the set up on and hear what it sounds like. Also glad to hear that there isnt too much difference whichever way I go. Ive got one place close by that will do the X but nobody really wants to tackle an H pipe on this car. I'd like to do the H but I think Im going with the X. Id rather have a better sound than 4 more horses but we'll see what gets done.