pre cat problems

[thumper316]

went to the mitsuibishi dealership the other day for the check engine light. said that the pre cat was out. was thinking of putting headers on my 4g64 and was woundering if i would still need the pre cat or could i run a header an stay away from having to buy the pre cat?

[99galantES]

i had that problem and i replaced me pre cat but youd prolly need the pre cat if the headers arent long enough to replace the length of the pre cat

[thumper316]

o ok do u know a good set of headers to go with prob end up putting a full exhaust on it?

[Reelax]

i had that problem and i replaced me pre cat but youd prolly need the pre cat if the headers arent long enough to replace the length of the pre cat

huh? headers take the place of all the cats.

[Boosted]

As far as the 4G64 is concerned, there is only one header. You can get an OBX or an Ebay header and it will work just fine. You won't see a big performance increase but it will look "purrty" in that engine bay.

SN: We have another NC member?

[thumper316]

i was looking into the kamakazie brand also because i hear the obx wasnt to good. but i was goin to get a set of headers an see if i needed the pre cat or if i could just run the headed without it an not have the service engine light on. but goin to redo the exhaust becasue the muffler insides are coming apart and sounds crap when u get into it. not bad at idle an crusie but high rpm u can hear it real good.

[thumper316]

yea im from NC. not to many hooked up 8g galants that i have seen. usually the hondas and eclipses that i see. but i have seen some really nice ones that are boosted. but have been trying to find someone that has a dohc head for my block and doing a NA build but dont really know were to start.

[Boosted]

Kamikaze and OBX are going to have similar sound and performance gains so it really doesn't matter which one you get.

[RAZ_76]

As far as the 4G64 is concerned, there is only one header.

Yes and no, On a Fed Spec there's only one, under. On a Cali spec, there are two cats, one on the header and one underneath. I've had both, that's how I know.

Fed Header on my 01 after I swapped them between my 99 and the 01.

http://gi153.photobucket.com/groups/s220/MVVGKWHGP5/01G017.jpg


Cali spec header on my 01, you can see the cat.

http://gi153.photobucket.com/groups/s220/MVVGKWHGP5/01build019.jpg

Fed spec pipe on the left and Cali on the right.

http://gi153.photobucket.com/groups/s220/MVVGKWHGP5/stuff012.jpg

[thumper316]

i have one thats right under the header before the downpipe then i have one thats the main cat. i have replaced the main cat an i have to get the one right off the header just didnt really wanna get in if i didnt need it with an after market header. which would be best for the long haul like the ceramic coated or the polished?

[RAZ_76]

i have one thats right under the header before the downpipe then i have one thats the main cat. i have replaced the main cat an i have to get the one right off the header just didnt really wanna get in if i didnt need it with an after market header. which would be best for the long haul like the ceramic coated or the polished?

Yes, you have the Cali spec. Ceramic all the way, more expensive but worth it. Also make sure the header has a spot for your sensor or you'll throw codes.

[thumper316]

so if i get the ceramic can i put the pre cat at the end of the header before the main cat or do i have to put it right off the top where its at now?

[RAZ_76]

so if i get the ceramic can i put the pre cat at the end of the header before the main cat or do i have to put it right off the top where its at now?

If you get an aftermarket header, you eliminate that cat and will only have the main cat, that's why you need to make sure the header you get has a bung for your sensor since the cat is not there anymore.

[thumper316]

sweet thanks saves me some money being the dealer was goin charge me about 200 for the parts and another 200 for the labor. but if i go with the obx or the kamakazie they should have the bung for the sensor? but kinda save me a headache cuz i asked them an they said the engine light would stay on.

[RAZ_76]

sweet thanks saves me some money being the dealer was goin charge me about 200 for the parts and another 200 for the labor. but if i go with the obx or the kamakazie they should have the bung for the sensor? but kinda save me a headache cuz i asked them an they said the engine light would stay on.

Go with Kamikaze and yes it should have a bung for your Sensor but call and ask them to make sure. If it doesn't, a good muffler shop can get one on there for you and you should not have a light anymore.

[thumper316]

ok will go ahead an order the header an see. been trying to decide on one for a while guess good time to get one. an if need to i can hit up the shop see what they can do to get a pre cat on if needed. thank you for the info.

[thumper316]

do u happen to know anything about the evo head swap or a dohc that will work just as good on the 4g64 block? been looking but just wanting to do a sleeper an build a NA build.

[Boosted]

The heads you can swap onto the 8G 4G64 block are the Evo (4-9), Hyundai Sonata, and Kia Optima.

[thumper316]

o ok i was thinking about the evo 8, but hard to find around here. but i will check an see if i can find one off a sonata or optima, couldnt remeber the hyundai that would work.

[RAZ_76]

ok will go ahead an order the header an see. been trying to decide on one for a while guess good time to get one. an if need to i can hit up the shop see what they can do to get a pre cat on if needed. thank you for the info.

Just get this out of your head, once you go aftermarket on your header, there's no precat no more, you can't install a precat. You just need a bung, or a hole with threads on the header itself so the sensor goes there and fools the computer in thinking that there's one there so you don't get a light. As far as the Head swap, there are a bunch of threads here in regards to that. A quick search will give you that info since many people have done it.

[thumper316]

aight kool thanks.