I've been considering getting a dual exhaust for my xB for no other reason then I think that it looks cool and some of the ones I've heard sound great (Borla). However, the point was made somewhere on this forum that splitting the exhaust into two mufflers and adding the weight of all the extra piping will actually decrease HP? Is this true? I'd be willing to sacrifice a slight gain in additional hp from a new exhaust, but will adding a dual exhaust be a wash or even worse a hp downer? My auto trans needs all the help it can get. Any insights would be appreciated. Thanks.

 

From what i've heard, having a dual exhaust on our scions does indeed decrease hp. If it ends up to be very little and you won't feel the difference, its up to you. As you say you want it more for looks.

 

Well, there is a difference between a "true" dual exhaust with dual pipes from the cat back, dual mufflers etc., and a dual tip exhaust like the one Borla makes. The dual tip exhaust from Borla is just that, one pipe, one muffler, two tips coming out of that muffler to give you a dual exhaust look. This setup WILL increase horsepower in spite of a little (and by little I mean like maybe 10 - 20 lbs) extra weight from the second pipe and tip coming out of the muffler. Because basically it is still a single exhaust with plenty of backpressure for your engine to operate more efficiantly. However a "true" dual exhaust with dual mufflers etc. WILL decrease power because of the lack of backpressure. Plus, instead of adding 10 - 20 lbs you will be adding maybe 50 - 100 lbs. Plus it will sound like ___ unless your pipes from each muffler are the EXACT same length. The sound frequencies will clash and some will cancel each other out and some won't and you'll be left with an exhaust that sounds like total crap. Especailly on a 4 banger. Anyway, sorry for the long winded response. To sum up, Borla or any dual tip exhaust good, "true" dual exhaust bad!!!

 

Thanks for the response! In the case of "dual tip" (the Borla for example), would there be any performance difference between the dual and the single cat back or is it pretty much cosmetic?

 

i would go with a single. dual exhaust is too much for the little engine.

 

When you say that the dual exhaust is too much for the xB engine, are you referring to a dual tip such as the Borla? I thought that the Borla and exhausts like it used one muffler and just had two tips that came out if it. Does splitting out of the single muffler put strain on the engine?

 

did you not read what rattmobbins said?

 

i mean an actual dual exhaust. having a dual tip is not a big deal.

 

I did read what he said Bluebox. That is why I was a little confused when ikonxone (a regular and very knowledgeable contributer to this forum) said that the dual would be too much for the xB. I was trying to determine if he was talking about the true dual or the dual tip (with one muffler like the Borla). I also was trying to determine if the extra $250 for the dual tip Borla was purely for the cool factor, or was there any performance difference from the single cat back. I understand that there is a small 10 or 20 pond difference, but is that the only difference? Perhaps there are other elements to the dual tip that would derive performance enhancements. I don't know I'm simply asking.

 

 

Nice EV! I love the way that looks. Did you cut the second hole yourself? I understand that Borla includes a cut out pattern. Did you need to paint the lip where you cut? I was hoping that it could be done with a few coats of touch up paint along the lip. Is this possible? Also, would a Dremel cutter be sufficient to cut with or would I end up screwing up my bumper? Thanks.

 

Borla cut the 2nd hole for me. If you have a dark colored xB, there is no need to paint where you cut.

note the photo dual muffler..its not single muffler/dual tip

it's dual/dual

 

I really think that having a true "dual" exhaust systems on the 1.5 is releasing way too much backpressure, making you actually lose a small amount of power compared to having just a singular exhaust.

I guess if people find that it "looks cool", it's a whole nother story.

 

wrong.

first of all, since you have 1 pipe, that splits into two, if anything dual exauhst is going to add backpressure not have less. Dual exauhst ist completely pointless and cosmetic on an inline engine.

secondly, even having no muffler at ALL does NOT reduce low rpm power at ALL, this has been shown on the dyno and in my own experimentation at a road course.

 

if a inline engine is tuned to a true dual exhaust then it will work, but most of the time people just slap on a split muffler and leave it at that.

 

I called Borla today and asked about the differences between their dual and single. Here is what they (not I) said. While this might not apply generally to the differences between singles and duals, when it comes to theirs, they claim that there is virtually no performance difference. They have used smaller pipes on the duel to create more back pressure. They claim that the average hp gain to the wheels for the single is 6 hp and for the double 5 to 6 hp average. I should have asked about torque, but did not. Anyway, other difference is in sound. The dual is quieter and the single is a little louder, but deeper and throatier (so they say). An other point that someone made to me today is that once you cut the second hole in the rear bumper, you are married to the dual unless you are willing to kick down for a new bumper, fill it in some how or have an empty hole. All being said, the dual doesn't seem as cool to me as it did yesterday and I'm thinking its either the cat back, single Borla or the Magnaflow. Any opinions on the the two? FYI the dual Borla is on the street as of this week and the best price I have seen for it so far is $518 at Nopi.com.

 

Well let me tell you what I am gonna do. Since you obviously are not buying the xB for racing purposes (and if you are---sorry you are disappointed) then losing hp isnt that big of a deal granted losing what little you got kinda sux. I got the Lip Kit and I am going to get a custom dual exhaust done to my xB. Let you know if the loss is noticeable

 

I'd love to see some pics of the kit and exhaust when its on. I bet it looks great. I'm not one for racing at all, but my little auto transmission needs all the help it can get! I don't know where you all are from, but here in LA people are trippin out on the road. Having a little extra juice is an issue or practicality and safety more then anything. With all the inconsiderate drivers out there, changing lanes can be a challenge in rush hour without a little extra under the hood. That's where I'm comin from.

 

 

What system is this?