View Full Version : Exhaust, Cat, Header confusion....

05-26-2009, 07:10 PM
So my '92 GT Auto has been having some acceleration issues. Especially topping out at about 3K revs and not being able to break through. Thing is, it is an intermittent problem.

The engine has about 160K on it and was rebuilt last year after a cracked head occurred. A few people have told me my cat may well be clogged at this point affecting basic performance. I would like to ascertain if this is the case.

I am not really interested in spending a lot of money as I have have big vacation plans later this year so would like to do this all myself in the easiest way possible.

I have heard that one such way would be to pull and gut the cat but then again it doesn't really sit comfortable with me about the environmental damage i'd be causing. I've also read a lot about flow dynamics and see this is not the brightest idea even if a gutted cat flows better than a clogged cat, it is still not ideal.

So what are my options? I have been looking at getting a replacement header such as one from a later camry but apparently have to have some custom exhaust work done. Isn't this getting expensive again? Ideally i'd like to get a replacement (high flow-ish) cat and a lighter, better header that I can just bolt on myself (not massively mechanically inclined but I think I could manage that) without having to take it to a shop and pay through the arse. Is there anything suitable out there? I looked at the surewin header on ebay but would that eliminate my cat? Plus i really don't want to make my car much louder. A little is fine but nothing immediately and excessively noticable.

I've read through tons of threads and frankly am still a little confused as to what would give me the best ratio of economy, performance and ease of installation.

Help is enormously appreciated.


05-26-2009, 08:28 PM
Not sure why you want to keep the cat.

Go check ebay, you can get a direct bolt on header, that deletes the cat, and has the flanges for the 02 sensors already there, for about $120 shipped.

The Captain
05-26-2009, 08:29 PM
I bought a brand new gen-u-wine Toyota cat for my folks 97 vert for about $120. You have to remove your heat shields and put them on the new one.

05-26-2009, 08:33 PM
I bought a brand new gen-u-wine Toyota cat for my folks 97 vert for about $120. You have to remove your heat shields and put them on the new one.

Or you could do this. I think they are like $107 from the parts store, but that isnt a direct bolt on, needs to be welded.

The toyota one gt4rcdude is talking about is direct fit, bolts right on.

Or you could buy the headers/cat delete for same price, and watch it change a cool rainbow color after about 3k miles :)

05-26-2009, 09:08 PM
http://cgi.ebay.com/ebaymotors/TOYOTA-CELICA-GT-GTS-2-2L-5SFE-90-91-93-4-1-RACE-HEADER_W0QQcmdZViewItemQQ_trkparmsZ72Q3a1171Q7c66Q 3a2Q7c65Q3a12Q7c39Q3a1Q7c240Q3a1318Q7c301Q3a1Q7c29 3Q3a1Q7c294Q3a50QQ_trksidZp3286Q2ec0Q2em14QQhashZi tem3ef4cc83f7QQitemZ270395016183QQptZMotorsQ5fCarQ 5fTruckQ5fPartsQ5fAccessories#ht_3505wt_1048

Do you mean like that one?

Is it going to make my engine silly loud? And will my exhaust smell like rotten eggs without the Cat?

The Captain
05-27-2009, 02:08 AM
Personally, I'd gut the stock cat and see if your problem goes away. The header will run you $60 bucks. Yes, when you remove the stock cat that's a honeycomb ceramic substrate, you're exhaust will be louder. How much depends on how restrictive your muffler is, or if you leave the secondary cat in place.

If the environment is your top priority, and your cat gut job fixes the problem, just pony up and buy a new one. The secondary cat (if it has one) just takes longer to "light off", but it will clean up the emissions. I have a $200 Random Tech free flow cat in the secondary location and I pass emissions just fine. The car just has to be hot. If you could care less (this isn't a green lecture) then get the header. Worst case, you waste $60 or you can resell it on fleabay to cut your loss and buy the OEM.

The fact that it's intermittent, I'd check the coil/igniter first. Sounds like the coil is weak.

05-27-2009, 03:39 AM
Thanks gt4rcdude. I'm going to test the ignition coil. I think the igniter got replaced last year so I'll start with the coil. Plus it's the cheaper part to replace, considerably, so fingers crossed.

I may just get the surewin header and be done with it. I don't have a secondary cat and the muffler is stock. Is this going to be very loud?

05-27-2009, 06:26 AM
Gut the cat and see if that helps with the flow. Shouldnt be too loud, besides you should still have the stock resonator on there as well, which will help the sound.

And do everything that gt4rcdude said.

(sorry re read the thread, forgot the surewhin or whatever is the name of the ebay header)