did u get this

[youngcs]

for those of u that did the 4g63t swap did u replace ur downpipe???
and if you did, did u buy a new catback to connect to it or did u use the same stock galant catback?
I know that eclipse catback would require that you ad an extra section from the downpipe to the catback because it the catback was too short. I just want to know how much of this is necessary to get the car running sucessfully then after that I could work on upgrading If I so choose.

[JiP]

If the stock doesnt match up and you wanted to just use the stock catback for now, any muffler shop should have no problem extending the stock piping a lil to get them to bolt up.

[youngcs]

a 7g stock catback isn't 2.5" is it??
wouldn't that cause problems with the exhaust systemt that is 2.5 inches if the 7g catback isn't 2.5 inches?

[Livn2sk8]

no stock isn't 2.5".....if you are going to a muffler shop anyways...just throw that engine in there...with whatever downpipe you want to use....and have them run 2.5" the rest of the way.....and just use your cat and muffler.....

[the_kage]

use 3".
your not going to loose back pressure.

[seth98esT]

Any 2g GST Downpipe will bolt up. And I heard from Joe that the 2g GST cat back fits as well. I havent tried the catback yet, but I do have a 2g GST dp.

[youngcs]

yeah, that what I'm doing, I am buying a 2.5 inch bushhur racing downpipe I don't want to mess up my set up by etting back presuure from the change in pipping size

[Livn2sk8]

<div class='quotetop'>QUOTE(youngcs)</div><div class='quotemain'>yeah, that what I'm doing, Â*I am buying a 2.5 inch bushhur racing downpipe I don't want to mess up my set up by etting back presuure from the change in pipping size</div>


we all know you mean "getting" but...you WANT back pressure....

[youngcs]

The thing that I don't want is to get too much back preesure though

[youngcs]

would the reactive catback for a 2g be a good choice??

[seth98esT]

<div class='quotetop'>QUOTE(Livn2sk8)</div><div class='quotemain'><div class='quotetop'>QUOTE(youngcs)</div><div class='quotemain'>yeah, that what I'm doing, Â*I am buying a 2.5 inch bushhur racing downpipe I don't want to mess up my set up by etting back presuure from the change in pipping size</div>


we all know you mean "getting" but...you WANT back pressure....</div>

Not in turbo cars, we want to get rid of this hot exhaust as fast as we can.

[JiP]

<div class='quotetop'>QUOTE(Livn2sk8)</div><div class='quotemain'><div class='quotetop'>QUOTE(youngcs)</div><div class='quotemain'>yeah, that what I'm doing, Â*I am buying a 2.5 inch bushhur racing downpipe I don't want to mess up my set up by etting back presuure from the change in pipping size</div>


we all know you mean "getting" but...you WANT back pressure....</div>

You can run a turbo car with no downpipe at all it it kicks ass. In NA cars you want back pressure to create suction and draw the rest of the gas out of the chambers faster. Think of how a turbo works..it creates its own suction, another reason why turbos are efficient =D

[98ACR]

<div class='quotetop'>QUOTE(Livn2sk8)</div><div class='quotemain'>

we all know you mean "getting" but...you WANT back pressure....</div>

Man, everytime I hear that from an enthusiast I wanna smack them... backpressure is BAD....always. No exceptions. No, your buddy's car did not lose power by reducing backpressure. TURBULANCE in the exhaust is bad, and is often thought as a side effect of a "less restrictive" exhaust. This is why test pipes make more power than full exhausts. The key however is to keep all the piping all one size, or at the very least only go DOWN as the system goes toward the tailpipe. Once the exhaust hits it's most restrictive point, the piping from there to the end should never get larger than that most restrictive point. The only time backpressure is "good" is on turbocharged road cars where it helps the turbo spin up ever so slightly quicker. But even than, the power benefits of the larger exhaust outweigh the faster spool time (and we're talking maybe 1/2 a second faster)

[JiP]

um.. well yes... backpressure is always going to exist...but I tend to use the wrong terms.. high backpressure in any system is bad. In an NA car you cant put 3" piping because you loose flow speed and your low end becomes non existant, but if you have backpressure in a large diameter pipe system it will slow down the speed enough to make it usefull at low throttle and then it just hurts your high end. The faster the gasses move the more suction they produce and they draw out gas from the chambers (scavenging)... large pipes = no restrictions = lower flow speeds bad for low end power.

but on a turbo you dont have to worry because once the turbo starts to spin it produces the suction fo you.

[brandon]

Stock exhaust is 2 1/4" I believe...

I am using 2.5" turbo back on my 4G64. I opted for the 2.5" over a 3", running a smaller turbo (14b)... I didn't want to sacrifice torque in lower RPMs as my car is a daily driven street car. Been working well thus far.

If you often run your car in higher RPMs and are using a 16g or bigger, a 3" exhaust seems to be most popular.

[redboy]

yeah i bleive its 2-1/4. next weekend ill lhave my gst engine in and i alreayd have an sppointment with my boy at midas whos gonna make me a 3" custom full mandrell exhaust for it. cuz i heard some people haveing problems with the downpipe matching up and some other misc. things so ill just spend the less money it would cost for a (example) apex 3" ful exhaust. ill lose the "fully tuned" part of gettin an exhaust like that but ill save a chit load of money!

[evil-G-nius]

what can I do to get some back pressure back? I have no low end because of my exhaust. I have a 2.5 or 2.75 in. alll the way and there is little back pressure. Is it a lost cause? I know I dont want smaller piping!