burgy240

I have a topspeed 3" straight through exhaust and an Apexi N1 dual. &nbsp;I like the sound and looks better from the N1 but the performance with the SR should be better from the Topspeed single. &nbsp;I think the piping is only 2.75 on the N1 dual and my question is if I stay with the N1 dual how much power am I sacrificing and how bad would teh topspeed 3" be on the KA? <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/cry.gif" border="0" valign="absmiddle" alt=''> Thanks, and no I won't sell the N1 dual &nbsp;I have 2 s14's and need 2 exhausts.

__________________

burgy240

Anybody??? <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/blush.gif" border="0" valign="absmiddle" alt=':blush:'>

__________________

uiuc240

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (burgy240 @ Dec. 09 2002,5:37)</td></tr><tr><td id="QUOTE">I have a topspeed 3" straight through exhaust and an Apexi N1 dual. I like the sound and looks better from the N1 but the performance with the SR should be better from the Topspeed single. I think the piping is only 2.75 on the N1 dual and my question is if I stay with the N1 dual how much power am I sacrificing and how bad would teh topspeed 3" be on the KA? <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/cry.gif" border="0" valign="absmiddle" alt=''> Thanks, and no I won't sell the N1 dual I have 2 s14's and need 2 exhausts.</td></tr></table><span id='postcolor'>
Ummm, I'm gonna go ahead and say that there is no difference between one 80mm pipe and one that splits into 2 60mm pipes. &nbsp;They will flow roughly the same. &nbsp;The most crucial point on a turbo exhaust system is the downpipe, the cat, and the midpipe, anyway. &nbsp;By the time the flow is at the rear, most of the thermal energy is gone, it's cooled down alot, and doesn't need as much diameter (low temp = more dense = smaller).

But, I'm sure some tool &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/alien.gif" border="0" valign="absmiddle" alt=':alien:'> will come over here and tell me why the 3" single is better. &nbsp;I'm saying they are totally equal and the only difference is LOOKS.:thumbsup:

Now, if the single were like the GT Spec (95mm), that would be a different story, of course.

Eric

__________________
2002 Mazda Protege5
1989 S13 w/SR20DET (sold)

kandyflip445

Don't know which would be better but the point of using two smaller diameter pipes is that it increases velocity <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/baaa.gif" border="0" valign="absmiddle" alt=':baaa:'> It's usually to help scavenging but don't really know for a turbo. I'm guessin that the N1 Dual would have more backpressure and would help the turbo spool but if i'm wrong someone will probably correct me. <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/tounge.gif" border="0" valign="absmiddle" alt=''>

__________________
My 240 vBgarage

Steeles

why would the dual have more backpressure? &nbsp;it definately reduces velocity of the exhaust. &nbsp;But Im curious as to how why it would create more backpressure?

__________________
Keeping it Godzira bishes.
So I murdered another turbo

Foxcolt

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (uiuc240 @ Dec. 09 2002,11:25)</td></tr><tr><td id="QUOTE"></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (burgy240 @ Dec. 09 2002,5:37)</td></tr><tr><td id="QUOTE">I have a topspeed 3" straight through exhaust and an Apexi N1 dual. I like the sound and looks better from the N1 but the performance with the SR should be better from the Topspeed single. I think the piping is only 2.75 on the N1 dual and my question is if I stay with the N1 dual how much power am I sacrificing and how bad would teh topspeed 3" be on the KA? <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/cry.gif" border="0" valign="absmiddle" alt=''> Thanks, and no I won't sell the N1 dual I have 2 s14's and need 2 exhausts.</td></tr></table><span id='postcolor'>
Ummm, I'm gonna go ahead and say that there is no difference between one 80mm pipe and one that splits into 2 60mm pipes. They will flow roughly the same. The most crucial point on a turbo exhaust system is the downpipe, the cat, and the midpipe, anyway. By the time the flow is at the rear, most of the thermal energy is gone, it's cooled down alot, and doesn't need as much diameter (low temp = more dense = smaller).

But, I'm sure some tool <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/alien.gif" border="0" valign="absmiddle" alt=':alien:'> will come over here and tell me why the 3" single is better. I'm saying they are totally equal and the only difference is LOOKS.:thumbsup:

Now, if the single were like the GT Spec (95mm), that would be a different story, of course.

Eric</td></tr></table><span id='postcolor'>
Don't forget that the o2 housing plays a big part. With a 3 inch exhaust the most restrictive part will be the o2 housing. I placed both a stockie and an hpi one that I plan on buying side by side and the difference was amazing.

Sorry not really on topic but something to think about nonetheless.

Jed

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Driftec
www.midatlantic240sx.com

uiuc240

You are correct, Jed. This is one of the reasons I'm considering getting a nice tubular mani and a nice stainless o2 housing when I plop my S14 turbo in. Might as well. Shit, it's a big enough job. Don't really want to do it twice...er THREE time (since I just replaced those gaskets 3 weeks ago) <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/sad.gif" border="0" valign="absmiddle" alt=''>

Eric

__________________
2002 Mazda Protege5
1989 S13 w/SR20DET (sold)

240fluke

Well, this is not an entirely "fair" comparison since you are comparing two different exhaust systems. &nbsp;A closer comparison would probably be like the N1 single vs. N1 dual. &nbsp;In which case I would probably say that the difference in overall HP is probably minimal to the point that you would not notice a difference in HP (like maybe 1-3 HP) if any at all. &nbsp;The Dual exhaust system will help you maintain more mid-range power (which I would assume would also keep the lower range of the power band from suffering as much as well). &nbsp;This comparison would be between a 2.75 and 3 inch exhaust. &nbsp;Now if the difference in power was between a 2.75 inch and 3.75 inch (I think that is what 95/94 mm translates into) then i would say yes, you would notice a difference in power between the smaller dual piping and the larger single piping (probably in excess of 5 HP). &nbsp;

But, like I said earlier, since they are two different exhaust systems, one of them may outperform the other and that really depends on how the system was designed and how well it flows and how many bends in the piping there are (i guess a few factors).

"On a side note" - Looking at the GP Sports R Spec exhaust it has one big single pipe that splits into dual canisters right at the end. &nbsp;Now the Apexi N1 dual is a true dual setup as it has two pipes flowing from the cat back to each muffler. &nbsp;Looking at the GP Sports Setup, it might not have the potential for the same amount of HP levels as the N1 since it is not a true dual setup (however, I am very curious as to how it sounds in comparison to the N1 dual).

"On a stupid sidenote" - why did Apexi call it an N1 Dual and not an N2? hmmm.... <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/exclamation.gif" border="0" valign="absmiddle" alt=''> &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/wink.gif" border="0" valign="absmiddle" alt=''> &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/tounge.gif" border="0" valign="absmiddle" alt=''>

Tim '95 SE

Foxcolt

Why would an exhaust like the N1 dual with more bends provide more midrange power than a free'er flowing exhaust lke an N1 single?

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Driftec
www.midatlantic240sx.com

uiuc240

Slightly more backpressure perhaps? &nbsp;Or perhaps the dual pipes "act" like a longer pipe, thereby adding length, which equals midrange torque. &nbsp;I don't know.

Personally, I say it's a wash. &nbsp;They are both REALLY free-flowing...as are almost all decent aftermarket systems. &nbsp;Just buy the one you like, and rock that. &nbsp;If you need more power, turn up the boost &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/biggrin.gif" border="0" valign="absmiddle" alt=''>

Eric

__________________
2002 Mazda Protege5
1989 S13 w/SR20DET (sold)

Foxcolt

Right Eric, that would make sense on an NA car. But from my understanding any backpressure on a turbo car would only hinder performance and from looking at the N1 Dual all I saw were more reasons to create turbulance.

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Driftec
www.midatlantic240sx.com

uiuc240

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (Foxcolt @ Dec. 11 2002,09:16)</td></tr><tr><td id="QUOTE">Right Eric, that would make sense on an NA car. But from my understanding any backpressure on a turbo car would only hinder performance and from looking at the N1 Dual all I saw were more reasons to create turbulance.</td></tr></table><span id='postcolor'>
Jed, there is only *one* spot where the flow splits into two pipes. And then after that, you go from one 80mm pipe, to two 60mm pipes (ok, they taper, but forget about that).

The sectional area of the 80mm pipe (same as N1 single) is:

pi*(40^2) = 5026mm^2

The sectional area of the dual 60mm pipes is:

(pi*(30^2))*2 = 5654mm^2

I'm not saying that this is all the calculations that need to be done...physics play a big role here. I'm just saying that you're not losing flow area...infact, you're gaining 12%. I'm going to wager a guess that the 12% gain in area will offset the losses in laminar flow.

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote </td></tr><tr><td id="QUOTE">FROM APEX'I WEBSITE:::The N-1 Dual piping splits into two smaller diameter pipes just after the catalytic converter and flow into a pair of 120mm canisters. The canisters are polished off with aggressive 90mm tips. The use of smaller piping diameter helps retain more mid-range torque. The Dual N-1 does not sacrifice peak horsepower because the dual pipes can handle more exhaust gas volume.</td></tr></table><span id='postcolor'>

Eric

__________________
2002 Mazda Protege5
1989 S13 w/SR20DET (sold)

Steeles

lol that quote was one reason I looked at the N1 Dual <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=''> &nbsp;but I bought it for the looks <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/butbut.gif" border="0" valign="absmiddle" alt=':but:'> &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/inlove.gif" border="0" valign="absmiddle" alt=''> &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/tounge.gif" border="0" valign="absmiddle" alt=''> &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/thumbs-up.gif" border="0" valign="absmiddle" alt=':thumbsup:'>

__________________
Keeping it Godzira bishes.
So I murdered another turbo

Foxcolt

Right, My only question is why would it create more midrange torque on a turbo car? The only thing that backpressure does is make it harder for the turbine to spin. I don't see how that creates more torque.

I started thinking about this last night. And now I'm really curious. Plus I need to get rid of my Tanabe G force power medalion hyper can fart buster or whatever it's called. <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/laugh.gif" border="0" valign="absmiddle" alt=':laugh:'>

__________________
Driftec
www.midatlantic240sx.com

uiuc240

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (Steeles @ Dec. 11 2002,09:44)</td></tr><tr><td id="QUOTE">but I bought it for the looks <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/butbut.gif" border="0" valign="absmiddle" alt=':but:'> <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/inlove.gif" border="0" valign="absmiddle" alt=''> <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/tounge.gif" border="0" valign="absmiddle" alt=''> <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/thumbs-up.gif" border="0" valign="absmiddle" alt=':thumbsup:'></td></tr></table><span id='postcolor'>
HAHA!! &nbsp;Me too! &nbsp;I decided it was too unique to pass up. &nbsp;They only make it for the 240 and the RX-7!! &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/thumbs-up.gif" border="0" valign="absmiddle" alt=':thumbsup:'> &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/thumbs-up.gif" border="0" valign="absmiddle" alt=':thumbsup:'>

Eric

__________________
2002 Mazda Protege5
1989 S13 w/SR20DET (sold)

burgy240

I've crawled under the car and I've researched on my own....my conclusion is that in theory foxcolt and uiuc are both right. &nbsp;The bends may hinder performance but you do gain area of 12%. &nbsp;Anyway, I'm keeping the N1 and the Topspeed is going with the other s14.

__________________

uiuc240

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (Foxcolt @ Dec. 11 2002,09:45)</td></tr><tr><td id="QUOTE">Right, My only question is why would it create more midrange torque on a turbo car? The only thing that backpressure does is make it harder for the turbine to spin. I don't see how that creates more torque.

I started thinking about this last night. And now I'm really curious. Plus I need to get rid of my Tanabe G force power medalion hyper can fart buster or whatever it's called. <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/laugh.gif" border="0" valign="absmiddle" alt=':laugh:'></td></tr></table><span id='postcolor'>
Dude, Jed, I have no farking clue. &nbsp;Hahaha. &nbsp;I figure, that far back in the flow, it can't possibly matter that much. &nbsp;If you're really worried about flow, you need a GT Spec...then there is no debate, cuz your ish will be bigger than all the rest. &nbsp;95mm!!! &nbsp;whoa. &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/wow.gif" border="0" valign="absmiddle" alt=':0'> &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/wow.gif" border="0" valign="absmiddle" alt=':0'>

Anyway, I don't know how it makes more midrange. &nbsp;Maybe it doesn't. &nbsp;Maybe they are making it up. &nbsp;All I know is that mine sounds great, looks great, and I know it's flowing free enough to pop and warble and blap on every shift when at full throttle. &nbsp;yay!

Eric

__________________
2002 Mazda Protege5
1989 S13 w/SR20DET (sold)

Steeles

we should email all this to an Apex'i rep and see what they have to say lol

eric - yeah I actually had an N1 on backorder but then I saw a dual in person and had to have it lol. &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/inlove.gif" border="0" valign="absmiddle" alt=''>@1st <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/lookaround.gif" border="0" valign="absmiddle" alt=':look:'>

__________________
Keeping it Godzira bishes.
So I murdered another turbo

Foxcolt

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (uiuc240 @ Dec. 11 2002,09:50)</td></tr><tr><td id="QUOTE"></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (Foxcolt @ Dec. 11 2002,09:45)</td></tr><tr><td id="QUOTE">Right, My only question is why would it create more midrange torque on a turbo car? The only thing that backpressure does is make it harder for the turbine to spin. I don't see how that creates more torque.

I started thinking about this last night. And now I'm really curious. Plus I need to get rid of my Tanabe G force power medalion hyper can fart buster or whatever it's called. <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/laugh.gif" border="0" valign="absmiddle" alt=':laugh:'></td></tr></table><span id='postcolor'>
Dude, Jed, I have no farking clue. Hahaha. I figure, that far back in the flow, it can't possibly matter that much. If you're really worried about flow, you need a GT Spec...then there is no debate, cuz your ish will be bigger than all the rest. 95mm!!! whoa. <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/wow.gif" border="0" valign="absmiddle" alt=':0'> <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/wow.gif" border="0" valign="absmiddle" alt=':0'>

Anyway, I don't know how it makes more midrange. Maybe it doesn't. Maybe they are making it up. All I know is that mine sounds great, looks great, and I know it's flowing free enough to pop and warble and blap on every shift when at full throttle. yay!

Eric</td></tr></table><span id='postcolor'>
Yeah me I don't know either. It really bugs me though. oh well. I want the Jic-Magic full titanium, for the ultimate bling bling factor. &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/laugh.gif" border="0" valign="absmiddle" alt=':laugh:'>

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Driftec
www.midatlantic240sx.com

uiuc240

You fag. &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/laugh.gif" border="0" valign="absmiddle" alt=':laugh:'> &nbsp;Just kidding. &nbsp;That will be the sweetest exhaust on Zilvia, you know that, right? &nbsp; <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/cool.gif" border="0" valign="absmiddle" alt=''>

Eric

__________________
2002 Mazda Protege5
1989 S13 w/SR20DET (sold)

Steeles

lol yeah that would be like instapimp! &nbsp;I'd be happy with a full SS. &nbsp;I saw a Bee*R full SS system and was like <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/crazy.gif" border="0" valign="absmiddle" alt=':crazy:'> &nbsp;so sweet looking

__________________
Keeping it Godzira bishes.
So I murdered another turbo

Foxcolt

It's all talk at the moment. The last thing I need to do right now is start another project. I honestly think that I have the most projects going on at one time than anyone here on zilvia. Minus the people with shop cars <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/laugh.gif" border="0" valign="absmiddle" alt=':laugh:'>

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Driftec
www.midatlantic240sx.com