Exhaust Question

[tcam]

I currently only have a K&N Short Ram Air Intake, and lately have been doing a fair amount of looking at different exhaust pieces. I have decided that I like the Magnaflow cat-back exhaust, the JP performance custom mid pipe with a high-flow cat, and the DC sports Header. Now at some point I may want all of this put on, but for now I want to make sure that if I do eventually use all of these parts, I will actually get a fair performance gain. Because I remember reading once before that in order to achieve max. power, you actually need a small amount of back-pressure or something like this from your exhaust. And that by adding a header with a custom exhaust doesn't really add much more power beyond what the custom exhaust already gives.I guess what I'm trying to say is, "does making your exhaust as free-flowing as possible, truly give you large increases in horsepwer? Or would I just be better adding one of three pieces I'm interested in? Instead of everything all together?"sry to be so confusing, but I hope someone can help correctly advise me.

[northvibe]

a ported header gave great improvements. the DC actually showed some loss along certain parts of the power band. the 1zz (base or AWD) vibes have very restricted exhaust headers. I think the avg header hp gain was around 8 or so... Im still waiting to see the 1zz ported header dyno from boosted2.0's ported headers on newcelica.org but the flowbench shows big gains. Its not a big deal to just install piece by piece, thats what i am going to do. I think exhaust was like a 5-7hp gain and headers so your looking at like a 12-14 hp gain with exhaust and of course a nice sounding sound out the back

[tcam]

nice, those #'s sound pretty good. To get the exhaust manifold ported would be around $200 or so right? Do u know how useful it would be to port the intake manifold also?

[JustinVGT]

It has been a couple years since I last read up on the 2zz headers, but back then I read someone tested out several aftermarket headers. They found that the stock 2zz header actually performed better than the aftermarket headers. There was actually a loss of power with the aftermarket models. Apparently Yamaha did a good job designing the stock 2zz headers. Maybe there are better aftermarket headers now, but I do not know for sure. I decided back then to only modify my exhaust and not bother with my headers.

[tcam]

so do you think it would work well to put in a high-flow cat, along with the cat-back exhaust?

[northvibe]

oh you have a GT, ported headers gained like 10hp i think with stock ones ported from Boosted2.0http://www.newcelica.org/forum...04266So with an exhaust system you would get even a little more. In his first post he has links to a couple GTS dynos which would be just like a vibe GT. He also lists his prices for porting and its under $200

[Mrizzle05]

the high flow cat would give you more air flow... and you do have a GT so you should get maybe an extra HP. nothing big cuz its just freeing up air your car is producing.

[tcam]

alright, I'm liking what that Boosted2.0 guy does. but is the Celica GTS header identical to the Vibe GT header. i.e Would I be able to order one of his ported headers and then ship him mine, or would his already ported Celica header not fit?

[Mrizzle05]

Im not sure.... they might be... check online and see if they look the same engine wise. or wait till someone posts that might know. cuz i sure dont.

[tcam]

k, thnx

[tcam]

does any1 know if the Celica header is the same as the Vibe Gt's?

[northvibe]

I wasnt sure so I bought a extra header and so I have one to port and one to keep stock incase i go back stock and i wont be out of a car for a bit. He does core charges but you'll have to pm him to ask about that, i think the celica's header is longer or bent different....

[tcam]

[QUOTE=northvibe]I wasnt sure so I bought a extra header and so I have one to port and one to keep stock incase i go back stock and i wont be out of a car for a bit[QUOTE]I like that idea a lot. How much are our headers and where do u buy them?