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My buddy bought a '96 3.8, I checked it out for him and everything looked "lightly" modded 'til I laid down and looked at the exhaust. Never seen it done like this. It's "True Dual" to the truest extent of the meaning. There's no cross over on the pipes at all. They also split and turn down and out at the sides. I had him start the car and he's like, "See, told you it sounded like a 'stang." I don't know about a 'stang but the car doesn't sound "bad" by any means, actually sounds pretty mean for having no mufflers and short pipes. (I'd guess he's missing about 8-10 feet of pipe (dual pipe considered) from where the pipes should go. Short pipe = more power?

The big question is, is it safe? No cross-over, I've only seen that on high horse drag cars, where the pipes are lucky to stay bolted to the headers considering the ammount of power being blown through them.

'96 3.8L V6, no cross-over, short pipes. Downsides? Possible engine damage potential? Thought it was morbidly bad to not have a balance point in your pipes if you go true dual?

As I said, the car sounds great, all considering. It does seem to have a bit more get up than my old V6, which had a Flowmaster "dual" exhaust. Even the tips are pointed to blow exhaust down and away from the car.

Opinions?
 

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i have true dual running magnaflow h.f. cats and 3.5" tips.......no meeting of the 2 pipes.........sounds ok in person but a video makes it sound like a tractor..... i am planning a means of crossover........either the di/do magnaflow......or an x-pipe. i lost my low end torque by lowering backpressure............as we know the v6 don't have much in the hp or torque dept. so why take more away........
 

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i have true duals and no crossover. a crossover will actually hurt performance unless its in the critical spot. so basicaly having no crossover is better than having a crossover in the wrong spot. and no engine damage will not occur there are plenty of high hp cars running true duals without crossovers. I see it on trucks with custom exhaust all the time actually.
 

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i have true duals and no crossover. a crossover will actually hurt performance unless its in the critical spot. so basicaly having no crossover is better than having a crossover in the wrong spot. and no engine damage will not occur there are plenty of high hp cars running true duals without crossovers. I see it on trucks with custom exhaust all the time actually.
but you also have a twin turbo v8 correct?
v6 wasn't meant for true duals w/ no backpressure. sure it sounds good, but it does slightly hurt off-line performance.
 

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but you also have a twin turbo v8 correct?
v6 wasn't meant for true duals w/ no backpressure. sure it sounds good, but it does slightly hurt off-line performance.
i agree, i just put on high flow cats with 2.5" downtubes to my midmounted magnaflow di/so muffler....felt like i lost tq off the line, and noticed the cat was hitting my floorboard, so i took it back to have them look at it and now i see i have bad motor mounts lol

so maybe i gained some but the mounts are holding it back, mounts to be changed sunday then we will see.
 

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w/ the stock set-up i could get a screech from my tires from a dead stop going straight. now its gotta be a hard turn or wet............... loss of backpressure=loss of tq.
 

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yes but it also doesn't help that you have all that weight of the stereo in your trunk....

my car isnt a go fast, cuz its a 6, so im making it diff by apprearance so i will be doing a rear seat delete/stereo setup this weekend.
 

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Maybe backpressure is bad? Loss of velocity is what causes the tq loss. The velocity creates a suction to help pull the exhaust out. Similar to using a waterhose to drain a waterbed 10 times faster than just siphoning it or washing away a puddle with a hose. If the hose had no restrictive nozzle the volume would have to be immense or the water would puddle up. Inertia is a powerful force.

Therefore bigger and/or shorter pipes could create less low end tq due to more exhaust staying in the cylinder. At high rpm's the smaller pipes that created suction become a restriction causing backpressure and hp loss. There is a greater volume at high rpm so the bigger pipes are 'tuned' for this range.
 

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Maybe backpressure is bad? Loss of velocity is what causes the tq loss. The velocity creates a suction to help pull the exhaust out. Similar to using a waterhose to drain a waterbed 10 times faster than just siphoning it or washing away a puddle with a hose. If the hose had no restrictive nozzle the volume would have to be immense or the water would puddle up. Inertia is a powerful force.

Therefore bigger and/or shorter pipes could create less low end tq due to more exhaust staying in the cylinder. At high rpm's the smaller pipes that created suction become a restriction causing backpressure and hp loss. There is a greater volume at high rpm so the bigger pipes are 'tuned' for this range.
so what would be the best pipe size for a 3.8 for hp/tq/sound in your opinion?
 

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yes but it also doesn't help that you have all that weight of the stereo in your trunk....
my car isnt a go fast, cuz its a 6, so im making it diff by apprearance so i will be doing a rear seat delete/stereo setup this weekend.
this is very true.........its nice to chirp the tires once in a while though
if i had another dd or no kids i'd do a rear seat delete but..............can't do it..
 

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well i plan on taking pics and whatnot of how i do it, so if you have questions let me know when/if you get around to wanting to do it yourself.
 

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w/ the stock set-up i could get a screech from my tires from a dead stop going straight. now its gotta be a hard turn or wet............... loss of backpressure=loss of tq.
its not a loss of torque typically as long as the modifications fit within the engine computers parameters for fuel trims ur gonna make soem more power, but its only a peice of the puzzle. the powerband gets shuffled up the rpm range. if people are gonna do even regular ol' true duals on their v8 cars the same thing is going to happen, this is why exhaust mods work best with at the very least intake modifications (more air in/out throughout the power band) if not valvetrain work as well(stiffer springs, longer duration cams w/ smaller lsa's things of that nature), not to mention the gears to support where ur making power.

so the whole argument over if backpressure is good or not is subjective, it all depends on which path u plan to take with respect to future modifications.

Travis
 

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Discussion Starter #13
I'd say your pipe size versus ammount of air flowing out would determine how much backpressure you can lose. I cut the mufflers off on my 4.6 but left the cats intact with an H pipe cross-over just before the wicked drivers-side dual pipe turn. Nothing but pure gain across the board for me. No dyno to prove it but I could feel a major difference, off the line, but major difference in the higher-RPM band, once it got off the line it was solid gone. The looks I'd get from the Camaro guys were priceless.. couldn't beat 'em though. Damn car is just too heavy, every camaro I'd go up against was a stick. :p
 

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w/ the stock set-up i could get a screech from my tires from a dead stop going straight. now its gotta be a hard turn or wet............... loss of backpressure=loss of tq.
nope its not loss of backpresure...backpresure is a bad thing. by going duals on a V6 your most likely using bigger pipes right? bigger pipe=less velocity=less scavenging=loss of torque at low revs. That has nothing to do with a balance tube. Turbo exhaust is a whole different story
 

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I know that when I took my stock exhaust and cut it off at the 3rd cat, it didnt sound good, and I lost A LOT of power.

But when I did my 2 1/4" duals that I gained some power and also gained some MPG on my fuel efficiency.
 

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nope its not loss of backpresure...backpresure is a bad thing. by going duals on a V6 your most likely using bigger pipes right? bigger pipe=less velocity=less scavenging=loss of torque at low revs. That has nothing to do with a balance tube. Turbo exhaust is a whole different story
Stay away from the Corral. I love these discussions. Go and run around the block breathing through a straw. Restricted intake and exhaust backpressure do not make more torque. Within the parameter of pollution requirements of the time, so much air could be used, mixed with the proper amount of fuel, with excess (least amount possible) being removed by a metal catylist convertor to end up with numbers dictated by some Senators aid sitting on the hill. Within all that the cam engineers were the last in the chain (should have been the 1st) to take what they had (f$%^&* straw)and maximize the performance. Where am I going, it's simple. An intake restricted motor that has the exhaust open up needs much less time to evacuate the cylinder. Exhaust gases are sonic when leaving the cylinder. Sound waves bounce and reverbrate which means they will try to fill any void. Cylinder is empty due to free flowing exhaust (before intake opens), exhaust waves try to refill the cylinder with spent gases. Cure? Cam designed for the straw being removed. Much different valve events. Scavenging is a part of a high performance, well designed combination. Stock exhaust manifolds do not scavenge. They can help though to prevent the reversion wave from trying to refill the cylinder with spent gases which if you open the intake system causes a whole nother set of problems.

Of course this could lead to another one of my favorite corrals: horsepower vs torque. Which is more important?
 

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Of course this could lead to another one of my favorite corrals: horsepower vs torque. Which is more important?

horsepower is a function of torque. tq x rpm/5,252

some modifications have proven to either hurt performance or gain nothing over the previous set up (be it stock or another aftermarket peice). most pollution controlled cars have within their factory tune, catalytic convertors and the smaller environmentally friendly pipes for the exhaust and air intake. with that said, with some modifications its gonna throw the tune off, and viola a seemingly large loss of power. although the parameters within the tune are usually somewhat broad allowing yous ome room for particular mods. with that said some ppl pick the corrrect exhaust setups as to not throw that tune off much and u will feel some difference. although i've never been fond of ppl following the butt-ometer as ur average joe wouldn't actually even feel the difference in a 10hp gain (then again if i went with buttometer id have lost money at my shop :) ) most of what people feel after new modificiations is somewhat of a placebo effect. its not that their car isn't actually running better, but typically the improvement is not nearly as much as they "predict" with the aforemented self dyno.

i've run a little over 1400 cars on various dynos at the different shops i've worked and owned, and tuned all but around 20 of them. I'm not an expert by any stretch of the imagination, but i am a realist and have seen it first hand, alotta major mods such as a full exhaust or larger air intakes, tb's intake plenums etc should be tuned. but soem of it is actually unnecessary for ppl looking to do only a few mods here and there, say for the purpose of having a better sounding car and some more mpg. with that, snag a set of 24 or 30 lb injectors (new prefered), get a cai, do some exhaust worka nd have someone DYNO tune it (not that mail order **** which i will admit some aren't too bad) u'd be suprised what this 4.6 can do with just that minimal amount of stuff.

sorry for the novel, just wanted to get everything i thought when reading over a few of the posts :)

Travis
 

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Discussion Starter #18
So anyway, back to the subject, are their any damage potentials to not having the pipes on a cross over (X or H, some kind). Or whatever gets the exhaust gas out does the job?
 

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So anyway, back to the subject, are their any damage potentials to not having the pipes on a cross over (X or H, some kind). Or whatever gets the exhaust gas out does the job?
damage potential? no. hanging up a few extra ponies, possibly. enough to pay extra to make sure one is in? not really. that x or h is mostly there to help balance out the exhaust flow which creates a little vortex within itself. its helpful to have it if its done properly. if you dont have it its not gonna hurt much if anything (performance-wise i mean). its better to not have it at all then to have it done half arsed!
Travis
 
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