those of you with exhaust Options

[cg97]

for those of you with exhaust, without a cat, did the CEL come on? or do i just need a header with 2 sensor spots? i know some guys who did the whole header exhaust thing and they had to put a high flow cat in, is there a way to get around a cat? thanks

[95CelicaST]

for those of you with exhaust, without a cat, did the CEL come on? or do i just need a header with 2 sensor spots? i know some guys who did the whole header exhaust thing and they had to put a high flow cat in, is there a way to get around a cat? thanks

Celicas have two cats. Take one out and you should be fine. I still have both though. No CEL's. If you have an aftermarket exhaust manifold then you will need to weld on a new bung for the second sensor. More info here clicky. Read step 10.

This post has been edited by 95CelicaST: May 15, 2007 - 12:37 PM

[cg97]

for those of you with exhaust, without a cat, did the CEL come on? or do i just need a header with 2 sensor spots? i know some guys who did the whole header exhaust thing and they had to put a high flow cat in, is there a way to get around a cat? thanks

Celicas have two cats. Take one out and you should be fine. I still have both though. No CEL's. If you have an aftermarket exhaust manifold then you will need to weld on a new bung for the second sensor. More info here clicky. Read step 10.

yeah so my understanding if you have 2 sensors in the header, u should be ok. now the place i was gonna get to do it was saying mandrel is about twice the price, does it make that much of a difference? or just nicer looking? if i go crush, i have to go bigger piping, correct?

[Negative]

for those of you with exhaust, without a cat, did the CEL come on? or do i just need a header with 2 sensor spots? i know some guys who did the whole header exhaust thing and they had to put a high flow cat in, is there a way to get around a cat? thanks

Celicas have two cats. Take one out and you should be fine. I still have both though. No CEL's. If you have an aftermarket exhaust manifold then you will need to weld on a new bung for the second sensor. More info here clicky. Read step 10.

Yeah but your car is OBD-I. His is OBD-II. o0black0o's car threw a cel when we did his even with both o2's hooked up. I've seen other cars do that also.

And yes mandrel does mean a difference and just bigger piping isn't going to make that up. Especially if you are talking about on the header. You don't want a crush bent header.

[cg97]

oh no, not a crush bent header, was gonna get this http://www.1supertoyota.com/products/rd10.htm, just wanted to see if there is a big deal between mandrel and crush, and if i should just pay the extra for mandrel, any opinions?

[95CelicaST]

Mandrel is always better than crush bent. Mandrel has smooth bends which allow for gasses to flow easily. Crush bend is several kinks making up one large bend.

On our cars you won't notice a difference, so do what is more geared towards your liking.

[root]

Celica's have two cats

Ummm, I only count the one that comes off the header, unless you're talking about the resinator further back.

[Negative]

oh no, not a crush bent header, was gonna get this http://www.1supertoyota.com/products/rd10.htm, just wanted to see if there is a big deal between mandrel and crush, and if i should just pay the extra for mandrel, any opinions?

Oh sorry. Yeah that with either crush bent or preferably mandrel would do you just fine. About 2.5" diameter for GT and IDK for ST [2 - 2 1/4"?]. The general rule of thumb is 1" per liter with N/A DOHC engine so 2" sounds right for ST to me. o0black0o had 2.5" and it sounded really nice. Don't forget to plan ahead to do a magnaflow [or similar] high flow cat and def don't forget the resonator. Mine has no resonator and sounds kinda ricey at WOT - beautiful at lower throttle.

Celica's have two cats

Ummm, I only count the one that comes off the header, unless you're talking about the resinator further back.

Your's is a OBD-I non-cali spec probably. Maybe only has one? There should be one in the downpipe portion of the header and one underneath the passenger seat. At least that's the way the 96+ and Cali Specs are.

This post has been edited by Negative: May 16, 2007 - 9:15 AM

[95CelicaST]

I had two cats when they removed my stock exhaust system

[Jaws4God]

95 OBD I

I just had a header installed and plugged in only the pre cat (one wire) and had the other plugged. (2 wire) (No CEL)

Then I bought a 2nd 02 and plugged that in (got a CEL)

Right now I unplugged it again (No CEL)

[root]

Maybe I'm missing somthing. Mine goes header->cat->flexpipe->res->muffler. Yes, mine is not a cali-spec.


But, I've been known to be wrong before, so let me know.

This post has been edited by root: May 16, 2007 - 3:21 PM

[Negative]

Mine went header->cat->flexpipe->cat->res->muffler. I'm not sure if it's diff cause you have the no-cali spec OBD-I or if you are just not seeing it. IDK