thoughts on this custom exhaust..

alright.. i was thinking yesterday and since i'm not going to be able to afford headers.. i might as well make the exhaust as good as i can from there back..

so here is what i came up with:

the opening on the back of the manifolds is 2.25" at its widest point, so what i plan to do is get 2.5" to 2" header reducers (2.5" is the smallest i've found but should work) from there have the 2" pipe run down to a dual 2" to 2.5" outlet Y-pipe.. from there have it go through a 2.5" high flow cat, through more 2.5" pipe back to a 2.5" 40 series flowmaster and out the beautiful dual tips..

let me know what you guys think about this and if this seems like a decent set up or what

I was gonna do the same thing but I just haven't had the time or money. I was thinking of 2 1/4" piping to the cat(s). I wasn't sure if 2 1/2" wouldn't be too big? I also have a spare stock cat sitting around so I was debating on running a cat for each main pipe and placing the y later down stream?

2.5" is fine (plus the only DIRECT FIT convertor for nissans is 2.5")..well..the only one i saw

2.5 after the Y ya, I can see thatl. But as a main? it just seems a little big? *shrugs* if some one does it and it works I might do it???

2.5 after the Y ya, I can see thatl. But as a main? it just seems a little big? *shrugs* if some one does it and it works I might do it???
what do you mean?? the pipe going from the manifold to the Y-pipe will only be 2"

The 2.5" to 2" header reducers threw me off. Sorry I should learn to read things a little better before I comment... now by using that reducer wouldn't that cause a small amount of turbunace or pressure right at the manifold? ea individual exhaust port is 1 3/8" so the piping leading from the port should be the same. So in a very small amount of space its going to go from 1 3/8" up to 2 1/2" then back to 2"? It would depend on the length of the reducer but I think we're talking about some were between 6-12 inches? sorry I'm really not to trying over complicate this or rag on your idea but like I said I wanted to do this too and I'm just trying to take everything into account. btw... does any one have a comment on using 2 cats? do you think doing this and placing the Y farther down stream would help any?

i'm gonna make this exhaust system.,., i've ordered the 2.5" high flow cat and muffler.. with the header reducer i think i'm going to try and have like a short piece of pipe welded in so that the diameter never gets bigger than 2".. i'll post a pic of what i'm talking about later on when ive got some time

update: the muffler and cat that i ordered before i could never get, b/c i kept trying to pay the guy on ebay but he never responded to any phone calls or emails :lame:

so anyways.. NOW i tried again,.. and ordered (and paid for) a 2.5" cat and muffler and should hopefully have them by the end of next week.. i also went and got the 2.5" to 2.25" header reducers (for $10/pair!) and i lined them up with an extra exhaust gasket i had for the VG and theyl lined up perfectly...

however, i was wondering if i could get some help from any of the VG guys.. on the stock y-pipe, where the pipe connects to the mani.. there is like a piece of pipe that extends past the surface of where it connects to the manifold (like it goes into the manifold), i was just wondering if anyone knew the exact lenght of that piece.. b/c i want to have my new custom pipe ready before i take the y-pipe off

however, i was wondering if i could get some help from any of the VG guys.. on the stock y-pipe, where the pipe connects to the mani.. there is like a piece of pipe that extends past the surface of where it connects to the manifold (like it goes into the manifold), i was just wondering if anyone knew the exact lenght of that piece.. b/c i want to have my new custom pipe ready before i take the y-pipe off

as far as i can tell, that "extension" your mentioning is just to help a) the exhaust air channel into your y-pipe b.) guide the pipe on the right way (how u could screw it up, i dunno!), so id say go with no more than 2 inches lengthwise..if that makes sense...but another opinion would be good

I want mine to be 2.25" from the exhaust manis straigh back they hit an "H" pipe and then turn gradually 90* and exit just behind the doors with a couple of Glass packs and 2 flowmaster mufflers no cat.

I have a setup similar to what you're speaking of Paul. Here's what I did: http://www.streetneeds.com/uploads/cars/Ryan200SX13.jpg

Personally, I think you might lose a bit of low end if you go with a true dual exhaust. Not to mention the ground clearance you would lose. I put the muffler where the cat used to be, so it's tucked up a bit, but I've still scraped it a couple times when I have my race tires on. If you put a muffler on the passenger side, it would really hang down a bit.

thats pretty cool what you got there.

i was just planning on glass packs. I have no muffler right now so i dont think it'd be that much louder.

Ricers pay $60 for my sound i got it for free (muffler rotted right off the pipe)

But i want the duels i got 2 cylender banks might as well right.

I still think you'll lose a noticeable amount of low end torque with such an open exhaust. But hey, try it and see. You can always change it later.

yeah but wouldn't it give a bit more top end? The high flow from each bank i think ould help up top and thats where it needs it

arrrggg,.. Ye pirates try to commandeer my thread! ye will be hung for treason! :no:

here are pics:
http://memimage.cardomain.net/member_img_a/721532_1_full.jpg
http://memimage.cardomain.net/member_img_a/721532_2_full.jpg
http://memimage.cardomain.net/member_img_a/721532_3_full.jpg

Coooooool.... that piping looks nice

HEY, wheres the flowmaster? lol no biggie...

"spooled" (sorry, dont know the name off hand) i didnt know the O2 sensor would function correctly if it wasnt hooked up after the Y..cool to see that, cause i've CONSIDEREd running true duals..but i wanna keep my low end torque..

yeah.. i was going to go w/ a flowmaster,.. but i got that muffler for like $37 shipped and i was trying to get that exhaust done, but save money where possible

overall i think it sounds pretty good tho