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Discussion Starter · #1 ·
any fitment issues at all for the first gens?

also, do i have to mess around with 02 sensors? or just remove the old dp and cat and put on the stillen?

i know i would only be left with the rear pre cat to gut, are there 02 sensors there that i hvae to watch out for?
 

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Misery said:
any fitment issues at all for the first gens?

also, do i have to mess around with 02 sensors? or just remove the old dp and cat and put on the stillen?

i know i would only be left with the rear pre cat to gut, are there 02 sensors there that i hvae to watch out for?
It's kind of a bitch to get in on when your on jack stands. You will probably find it easier to port out the bolt holes to get it on. If you don't you will have to get it just right to fit.

Gut the precat while your at it. It's not easy and not fun, but you need to do it.
 

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Discussion Starter · #3 ·
okay..so it does fit without modifications? meaning i dun have to bang the pipe into shape or something?

what does gutting the pre cat involve? just sticking a tube in and hammering away? are there 02 sensors in the pre cat and stock downpipe that i should be aware of?
 

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Getting it on is tough. You may want to get the front and rear on before attaching it to the catback. I was too tired (gutting precat) and just ported the holes.

There are two O2 sensor plugs that come with it. The 1G doesn't have rear O2s. You will need to put these plugs on last. The rear one interferes with one of the downpipe-to-precat nuts. You will need a swivel joint or a crows foot to get one nut on.

Gutting the precat isn't fun. It isn't like the cat material, which is ceramic. The precat has metal in it. For this, I recommend a drill with a fat wood bit and a crowbar/tire iron. It will take forever to gut it without the drill. Have googles or some kind of eye protection. I got metal in my eye and couldn't see out of it for days.
 

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My stillen fit perfect with no modifications whatsoever. Did not drill out holes, (it already has 4 holes on each flange for both first gens and 2nd gens) There is a trick to installing it though, and those that don't follow the trick will probably have some problems getting the pipe past the transfer case, especially on 2nd gens.

The trick is to install the back flange to rear precat first, do it loosely but solid enough so the pipe can hang from those nuts/bolts. Then loosely fit the front on, then tighten both down. I alternated back and forth from front to rear to make sure it went on secure and tight. Then after it was solid on the pre cat housings then mounted it to the factory catback.

Before mounting the DP, definitely gut the rear precat, it makes a world of difference and although is a pain and really a mess, is worth the time, and only takes about an hour with a drill bit and a wet vac.

There is no 02 sensors on first gens, at least not on the downpipe. Don't install o2 sensors before fully tightening the rear flange bolts or you will have to remove it to get to the bolts.

(my pipe was missing one of the plugs so I bought a generic o2 sensor, ground off the ends so it was basically a plug, and screwed it in. Seemed to work.

Lord Warlock
 

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Discussion Starter · #7 ·
use of o2 sensors

so when gutting the precat, i gotta be careful not to destroy the o2 sensor in the housing...and as for downpipe 02 sensors, i dun have to bother about those and can just plug up the holes meant for the 02 sensors?

thanks for the tips!
 

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To tell the truth, I never noticed an o2 sensor in the rear precat housing. It doesn't stick out anywhere where you really have to worry about hitting it while gutting the precat. But you do want to be careful not to drill thru the precat housing by accident. Replacing it would be a pain in the ass.

I used a 1 1/2 inch wide spade bit (wood boring bit to drill large holes) and a drill extension. Would be happy to sell it to someone that wants it, 5 bucks plus shipping. I also used the shop vac to suck out the housing in between drilling holes thru the cat material. Made the job alot cleaner and only got a few chunks in my hair (ouch). My DP was my 2nd mod to the car and doing the rear precat was easy, just messy and awkward. Keep a drop light nearby so you can look inside and determine how much more work you have to do. I've read that some use a wire wheel attachment on a drill to "buff" or clean the insides out after the cat material has been gutted.

LW
 

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Discussion Starter · #10 ·
LW: thanks for the tip. i just dun wanna fuck up an o2 sensor somewhere...i figured there was one somewhere, my mechanic told me..but i just couldnt remembered if he said up front or rear or both. but i guess i can safely assume that there isnt one in the rear precat..OR i just have to be careful not to hit it...i mean, it would be pretty obvious that its a o2 sensor when i see it right?

its gonna be the first mod to the car...prolly follow with an air intake. i just dun like the idea of doing it all on jackstands...

SlowGSX: those are a little harsh on the wallet right?
 

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I didn't have any trouble installing my DP but gutting the rear pre-cat was a shitty ass job!! ahhhh... chunks in my hair and even with the goggles on I still got some in my eye. Its worth it, but not fun by any means!


I used a Big drill bit as well. also, used a big flat head screw driver and hammer to get the big chunks loose.

good luck and have fun:p
 

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Start of by gutting the precat, then if the turbulence is too much you can always install the eliminator later. Personally I don't see much of turbulence problem with the rear precat, flows great once the cat material is gone. No use spending 250 on a part that just replaces one housing, save the 250 to pick up a good boost controller (i.e. dsbc ) if you've got a turbo.

The air breather is a piece of cake once you get the factory air box taken apart and removed. No noticeable improvement with that mod though, at least until you've done a dp and catback.
I have the stillen intake and like it as well, looks neat but no improvements in power that I could tell.

I only had the front of the car on Jackstands, and backed up with the hydraulic jack. Is safe enough, got through muscling the downpipe on and off without knocking it off the stands.

After you remove the Downpipe, and put the stillen on, watch for smoke... as soon as mine went on, I started seeing smoke from the valve stem seals and had them done about a month or two later. New pipes usually smoke a little as it burns off the coating on the pipe, that isn't anything to worry about. And VSS smoke doesn't really hurt anything either, just embarrassing.

LW
 

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Discussion Starter · #14 ·
thinking i might go with the melton custom downpipe...looks like thats two cats to gut for me...gosh..might be needing to get that spade bit from you, LW ;)

the front o2 sensor is high up as well? (since i might have to gut this baby too) how much do these things cost to replace anyhoos?

anyone here got a clip of what the stillen sounds like with a stock exhaust?

LW: are you saying that the dp mod allowed you to see better if the vss were gone?
 

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Misery said:
thinking i might go with the melton custom downpipe...looks like thats two cats to gut for me...gosh..might be needing to get that spade bit from you, LW ;)

the front o2 sensor is high up as well? (since i might have to gut this baby too) how much do these things cost to replace anyhoos?

anyone here got a clip of what the stillen sounds like with a stock exhaust?

LW: are you saying that the dp mod allowed you to see better if the vss were gone?
The Stillen replaces the front precat. It doesn't have to be gutted because it's not on the car.

O2 sensors are about 60-80 bucks each. The front one is a BITCH to replace the first time. Some freakin Sumo wrestler puts those on and a O2 socket wont fit on it with taking the alternator out. I just cut mine in half with a dremel and got a 22mm open face on there.

I can't give you a decent clip. I have a Borla CAT back and that is totally different.
 

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Discussion Starter · #17 ·
welllll....i did say id hold off modding for a bit but damnit!! :D

im half way through snake eyes too...thought id be able to finish it up within an hour but realised i just couldnt get the harness out without removing the knee panel...so start removing then realise i need an extension for the rachet...and then it gets dark...and beginning to lose feeling in fingers...heh ;)

you were right dude...once you even start thinking about it...you just gotta do it

;)
 

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Its just that when the cats are in the DP and precats, some of the vss smoke seems to burn off before it ever gets to the tailpipe. I never saw any smoke before I removed the factory DP, but afterwards, started noticing a light smoking, which eventually got worse. Maybe the loss of backpressure has something to do with it, I don't know. Just keep an eye out after the mod.

LW
 
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