CaptainMorgan

I know people go 3" downpipe. What size is the stock size of an g3 integra? what do you do if its smaller then 3"? do you do a whole 3" all the way or do you adapte it so it goes back down to the stock size. does anyone know how mcuh cody charges for a down pipe and a dump.

Distorted

Any stock integra isn't gonna be 3''. The point of 3'' downpipe and exhaust is airflow. You can go bigger in diameter and shorter in exhaust length by running just a dump tube just in front of you motor , but this is overkill for most people. In a turbo application any and all back pressure is your enemy. It causes heat, slower spooling, boost distortion(lower boost, fluxuating boost), as well as just generally robs your motor and slowly breaks down your turbo. Its not bad and if you have a 3'' exhaust you probably wont notice any kind of damaging effects. If you open up your downpipe though, you'll notice additional power. If you ran a 3'' downpipe to a smaller diameter, make sure its no less than 2.5'' or you just bottle-necking the system and its worthless. I'm a fan of 3'' or greater for turbo cars as its not going to hurt if your too big, only too small. I myself just run an open dump tube right now

hybridcrx

Um......stock down pipe on a G3 integra???? Wtf are you talking about? If you mean you're trying to adapt a 3" downpipe to stock G3 integra exaust...you would have to get a downpipe which starts as 3" and tapers down to the stock size (2"??)but don't waste your money. Once you get a larger exaust you'll have to get a whole other downpipe to fit and if you're planning on keeping your exaust stock, I don't think there would be any point in having a 3" downpipe because your exaust is gonna restrict airflow.

I hope this helps????

CaptainMorgan

what if i went from a 3" downpipe to a y collectors then have 1.5 or even 2" comeing out, and point them to the side of the car like the svt's, right before the tires.

Jared

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by doubler &raquo;</TD></TR><TR><TD CLASS="quote">what if i went from a 3" downpipe to a y collectors then have 1.5 or even 2" comeing out, and point them to the side of the car like the svt's, right before the tires.</TD></TR></TABLE>

I'd call it rice. And it would probably hurt your performance. Changes in velocity inside the exhaust will increase backpressure. Use one exhuast. Don't split, don't go down in size.

30psi Teg

why dont you just run a 3" dp then just turn it down right by your steering rack.

quikB18B

Some poeple make things way to complicated

Why cant you get a 3" exhaust?

CaptainMorgan

Cause i cost to much to do it all the way 500. why would i be called rice, i don't see where it would be riced out, its for performance. This is the way i am thinking instead of haveing all those bend in my exhaust i can have the down pipe come down, meet a y collector 3" in and 2x 2.25 out, i'll put this right blow the shifter, just from there i'll put two pipes comeing to the sides, right before the rear tire. I was thinking about puting glass pack muffler between the tip and collector, or instead of running a collector, i will run a 3"i n and 2x 2.25 out muffler flowmaster, same idea but no glass pack.

quikB18B

Okay put it like this If you cant or dont want to spend $ on exhuast, then just run open donwpipe, it will be free and better than that custom rice fab your talking about .

Like i said keep things simple, besides you will probabaly get charged just as much for that domestic mullet sidepipe exhuast setup than a normal exhuast.

If you want to save some $ contact mkteller8, he does custom piping for cheap and can also get you a magnaflow 3" muffler to go with the piping.

Boofster

Here's something to think about...the exhaust side of a T3 is 2.5"....so why do we go into a 3" dp and then 3" exhaust? Wouldn't 2.5" all the way keep it flowing correctly? All I can think of is air expansion and free flow but then why isn't the T3 exhaust 3"?

hybridcrx

If you Y after the downpipe you will hurt performance. If you don't care about performance...then why even bother with a 3" downpipe? If the curves are done right, it won't hurt your performance (less than a "y" would anyway.) and $500??? Thats very steep for an exaust setup. Go to a local muffler place and they should be able to weld you up something way cheaper than that, then get a muffler and you're done.

boostlee

2 1/2 " downpipe with a 3" piping back should be good for you situation. thats what i am running on my h23 turbo

http://www.cardomain.com/id/boostlee

Darin D.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by doubler &raquo;</TD></TR><TR><TD CLASS="quote">Cause i cost to much to do it all the way 500. why would i be called rice, i don't see where it would be riced out, its for performance. This is the way i am thinking instead of haveing all those bend in my exhaust i can have the down pipe come down, meet a y collector 3" in and 2x 2.25 out, i'll put this right blow the shifter, just from there i'll put two pipes comeing to the sides, right before the rear tire. I was thinking about puting glass pack muffler between the tip and collector, or instead of running a collector, i will run a 3"i n and 2x 2.25 out muffler flowmaster, same idea but no glass pack. </TD></TR></TABLE>

Thanks for that. I needed a good laugh. I knew honda-tech was good for something.

CaptainMorgan

I don't see why a Y would hurt the performance. If the y collector is a 3" inlet, then it has a 2 outlet that are 2.25 each. So that is like going for a 3 to 4.5 other then the fact that it branches out into two instead of one. Does that make any sence or am i not get it.

boostlee

it can work, its just a matter of trial and error.

good luck if you go ahead with mod

Jared

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by doubler &raquo;</TD></TR><TR><TD CLASS="quote">I don't see why a Y would hurt the performance. If the y collector is a 3" inlet, then it has a 2 outlet that are 2.25 each. So that is like going for a 3 to 4.5 other then the fact that it branches out into two instead of one. Does that make any sence or am i not get it. </TD></TR></TABLE>

Any split in a single exhaust flow will hurt performance. Period. Keep it one size pipe all the way back, or don't do it at all. Open downpipe isn't all that loud anyway.

Distorted

First off, a good reason of many that Inline 4 cylinder engines run single exhaust, is that there is only one manifold. for exhaust. You like dual exhaust, buy a V-series engine or a flat 4 that has 2 manifolds(though most flat 4's run them back into one pipe). First off, just save yourself the hassle, and buy full 3inch from the guy here on honda-tech (can't remember his name so someone insert, sorry exhaust man, i hear you do good work), its worth EVERY saved penny. Short of that, run open downpipe at 2.5-3''. If you run 2.5, make sure you get a gradual pipe flare to your 3'' exhaust or you'll have exhaust flow problems in pressure. changing to the dual set up you suggested is an interesting idea, but its going to be heavier and cause exhaust pulse issues, your spitting up a good solid pulse and you'll cause poor flow by doing this. I doubt whoever is going to build this is going to flow test it for power. A single pipe is far more reliable a set up. Why not just run 1 pipe out the side in front of the wheel if your dead set on saving the cost of 3 more feet of pipe to the rear of your car.

Now, the question about why people run 3'' on a 2.5'' exhaust housing side. Think about the size of the wheel. Dont worry about the exhaust trim or stage of the wheel, think about the radius and the diameter. Now, if that wheel were bigger, it would take more force to spool it up, at the same time it would have mroe area to make use of your exhaust gas, but still, its intereia and all sorts of physics things that you can go learn on your own. Now back to not thinking about your trim and other exhaust side related things on your turbo. The turbo you bought, all those .63 trim exhaust wheel, well that has to do with the size of your wheel. Basically, if your housing were any bigger than the 2.5 your using, it would be a different turbo. A 2.5'' housing definetly likes more breathing room. You can suck a drink through a little wussy coffee sized straw, or you can go get that bigass slurpy straw and really get some flow.

In short, Just run open downpipe until you can afford the full 3'' or 3'' that dumps infront of the rear wheel or where ever you desire.

Full-Race Javier

if you wanna use the stock exhaust, use an e-cutout on the dp. you can connect the stock exhaust and the cutout to dp via a y-pipe or something similar. running the e-cutout will allow you to run an open dp with the flick of a switch (opening the valve)and running a very quiet exhaust with another flick of the switch (closing the valve).

rusteds2k

Is it ok if I use a 2.5" pipe from the t3 downpipe all the way to the exhaust, but uses the stock cat?(for now cuz of money problem) Would it cause any problems, power loss, or damage to the engine or turbo? btw: just got my turbo insatalled today and still a turbo noob.

Full-Race Javier

it shouldnt cause any problems other than being restriction. btw, you can pick up 3.0 in cats from ebay relatively cheap
http://cgi.ebay.com/ebaymotors...53064

superstud

if you're that strapped for cash that you can't afford a cat, i dont think a turbo project is right for you at this time. i'm doing mine over this winter and before i started, i made sure i budgeted to spend way less than i can actually afford. expenses tend to pop up here and there, and when you add a lot of power, things can break, so you'll want to have cash in reserve. just a heads up. waiting a bit before you start may save your car a lot of down time in the future!