HyundaiKitCoupe

so a few years ago meineke fuxored my custom straight through exhaust by putting my thrush before the cat. My car performed and sounded unimpressively. Now I got it all fixed and the guy did a magnificent welding job. My car has a lot more power, pickup, and responsiveness unlike before. It sounds good to, more growly! I'm so happy now, but I just wanted to share this so its clear the exhaust setup is very sensitive in how it is setup.

I will try to come up with some clips.

Gt headers>cat>thrush>magnaflow

Jason

Thats great!

It is very sensitive, thats why I never cheap out if i'm gonna get some exhaust work done.
But that pretty much goes for anything.

And magnaflows give a nice sound, I got one put on not long ago.

DTN

how were your o2 sensors positioned before the change?

HyundaiKitCoupe

Jason how did you go about extending your sensors? and is yours stainless steel? because mine is mild. it had a lot of buzz but the thrush got rid of that.

that was one of the "pending DTC" error codes, it would take so long for the second sensor to heat up, and even after that it was giving the computer bad readings. i'm nost certain that was the main cause of the lag.

i also hear that the apex'i exhaust is slanted like that for a reason, and the motoria is over axle for the same reason, because the exhaust has to be a certain length to maintain pressure and when you get rid of that length like i did by going straight and underaxle it f?cks with performance.

too late now, but last time i saw a civic/camry underaxle it was just like mine.

zoned019

This reminds me that I never made a thread with clips and pics of my new exhaust....
I've got THE best setup.
2.5" from the header back
hi flow cat -> 28" thrush glasspack -> CUSTOM made non-straight through muffler with a stainless steel custom tip
ARK piping (i got the last one available in the US)

and with my cai/bbtb/airram/headers...sounds amazing.

and its actually quiet. this muffler restricts only like 20% more flow than a straight through fart can, and is probably like 200% quieter. you can actually be on the highway and talk on the phone, or hold a conversation at normal voice levels. i love it.


anyway...HKC, have you ever used different headers? or always had the GTs? I was wondering if you get any of that buzzing? so your cat is right after your flex pipe? thats how it SHOULD be.

glad to know you finally got that stuff straightened out!

HyundaiKitCoupe

yeah man, that's how it should be! and you have th BBTB that i still don't have. i'm waiting for a good one to come out if it ever does. throttle issues are the worst. exhaust should never be waaay loud on any car because that's annoying. zoned you never put up any pics of that oval tip muffler. hop to it and get some clips on here!!

yeah finally got that straightened out for good. cat after flex. i've always had the gt's, but the glasspack eliminated 100% of that buzz for good. but i still have p0134, which i think is caused by the o2 not being wired right.

which sensor is Sensor 1? the one before or after the cat? it has to be after because the before one is giving good readings. i might go tomorrow to my friend shop and get things straightened out.

*sh-t i just read that P0134 has to do with PCV valve too. you think it's just best to go to a performance shop and have them try to fix this crap?

DTN

No. don't go to a performance shop for an o2 sensor code. You've got a great one here. It says your 2nd o2 sensor is not responding.

o2 sensor 1 = the first one from the exhaust (precat). o2 sensor 2 = the 2nd one from the exhaust (postcat).

Did you put on a universal o2 sensor? I remember there were 2 sets of wires which were the same color. You could have reversed the 2 grey wires. One is heater, the other is sensor. You're probly monitoring your heater lmao.gif .

What's the voltage reading from your diagnostics?

99mini

<div class='quotetop'>QUOTE (zoned019 @ Nov 27 2007, 02:17 PM) <{POST_SNAPBACK}></div><div class='quotemain'>I've got THE best setup.
2.5" from the header back
hi flow cat -> 28" thrush glasspack -> CUSTOM made non-straight through muffler with a stainless steel custom tip

and its actually quiet. this muffler restricts only like 20% more flow than a straight through fart can, and is probably like 200% quieter. you can actually be on the highway and talk on the phone, or hold a conversation at normal voice levels. i love it.</div>

in hindsight i wish i got a 2.5 inch exhaust.

i've got a 3 inch exhaust, hi flow cat, big resonator and the big muffler and it's too loud on the highway. i actually changed the resonator and muffler to get a quieter ride, and it made no difference at all.

i read somewhere that there's no such thing as a quiet 3" exhaust on a small car, and thats been my experience too.

i'm in the process of detuning my car to change it back to a daily driver. the hard coilovers, hockey puck engine mounts, 3 inch exhaust, etc just get too tiring. the more i modify my cars and bikes, the more respect i have for factory engineers...

HyundaiKitCoupe

^duncan, what kind of muffler and headers do you have? hahah, ride quality all depends on our wheel wells man. if our wheel wells were bigger we could have 235/45/17's and not feel as many bumps, like a G35. but since our cars are small and wheel wells are small we are forced to use rubber bands.

there was only 1 cat and two sensors. the first Pre-cat sensor is stock all stock and i did not rewire anything on it. All I did was plug it into the downpipe. The second post-cat sensor is the Bosch, and the wires might be wired wrong and it's plugged into the catco with bung behind it.

so Bank 1 sensor is the second post-cat sensor? that would make sense because it is a universal Bosch and i'm not 100% sure on the wiring.

99mini

^^the original 3" muffler was a dynomax (#17267) that was replaced with a 3" magnaflow (#14219). the headers were custom made for the turbo. the car has oversized 14" tires(205x60x14), so the sidewalls are pretty chunky by todays standards smile.gif