I thought you were replacing the 1st cat. It sounds like you did the 2nd. Did you do both?

...I just did the high position (first) cat. The rear O2 is located between the first and second cat, down low on the side of the midpipe. The only way to get to the rear O2 with the upper cat, header, etc still in the car is from the underside (because all of that stuff blocks access to it). From the underside, I could not get a wrench around the hex. Does that kind of make sense?

I am eventually going to replace the rear cat with a catless midpipe as well.

the heat shield on the cat isn't needed if you wrap up the MIL like I suggested in the pm I sent you. I just used some thick rubber hose to cover the MIL and o2 line and taped it all up. It looks stock and it's stiff enough to keep the line off the exhaust. Eaither way it'll work just fine, just a matter of personal preference I bet.

Glad everything worked out for you. I knew the topend would be a big gain. With my obx header it was the biggets improvement overall.

I am a bum... I said I would post the pics I took when I got this stuff, and I never did. Better late than never, I suppose. You can see how clean the inside of the WOMP catless DP is. Nice job, Matty. And, this is what the MIL eliminator looks like. Not much to it. Oh, and that stuff in the bottle? Don't forget to use it if you do this. I was going to take more as I installed the stuff, but the camera batteries died (and I wasn't waiting to finish it)!

A bit over a week since the install, and no check engine light, no problems. Just a sweet, cheap gain.

good deal. Would you say this is worth the $50 bucks you spent? What does the gain feel like over and above what you already had? If I had to guess I'd think your top end would just pul much harder with a slight loss of torque down in the very low rpms. Make sure to get an installed pic to show people what a sleeper is!

Totally worth the fifty bucks. You are right about the gain, except that you don't notice the torque loss that much at lower rpm (though I did feel it was diminished, slightly). Realistically, I would say it adds 3-4hp at higher rpm, as my "ass-o-meter" indicates.
Try to find cheaper hp than that... aside from the e-bay intake!
As far as the torque loss goes, it's as simple as launching it a little higher in the rpm's... problem solved!

yeah, thats what I figured. How did your exhaust sound change? I'd bet even with a stock exhaust it would sound real good. The wagner shorty and the gutted pre-cat should really change the tone.

Here are the pics. Please excuse the liberal application of anti-sieze EVERYWHERE... I will clean it up. Anyhow, this is after the install. Looks pretty stock... except for the MIL eliminator down below the cat.

looks good. Adding the heatshelds back to it really makes it look stock.

in all seriousness...you should REALLY consider having that manifold jetcoated. it wont look as "stock" but I think most people who see the header will know it's not a stocker. The jetcoat is a great coating for both performance, durability AND cosmetics!

I think I'm going to order myself another obx header and have wagner coat it up for me for my "sho-pro"

Matty You think you could hook me up with some detailed instructions/pics on how to gut the cat. I would ask you to send my one but shipping would make it kinda $$$$, plus I still havent recieved my shorty header that I ordered over a month ago. So I really dont want to ship it.

once you get the cat out of the car and seperated from the 90* bend piece on the bottom it's really straight forward. I used a pnuematic die grinder and a stone bit to cut through the substrate. Just kept drilling and cutting. When you get close to the edge there is a "chainmail" like skirt around it. I tried pulling it all out the top in one fast motion but it won't happen. Once you cut down the top side as much as possible flip it over and do it to the bottom. Break enough of that stuff out and then just use a long screwdriver and rubber mallet, start punching holes from the bottom of the cat to the top and this is when the really big chunks will start falling out the bottom.

p.s. DO NOT BREATH IN THE DUST! YOU WILL DIE!

enjoy.

Thanks...I dont have all the tools you got but when ever my header gets here I will take a wack at it. I'll make sure to wear my Pro Mask so I wont breath in the crap.

A little O/T here, but I really like your little breather. Does that work that same as a vacuum line? I have a little tiny k&n filter I tried to use for my r/c truck, I might have to put it on.

I know its old but im gonna bump this thread.
I got my header today and will be installing tomorrow. I will also attempt to gut the cat. But I got one question. If the cat is still there why did you need the MIL eliminator?

which header did you get? If you got the Wagner header you won't need to worry about the MIL (unless you're gutting the cat).

If you got the OBX header or AWR you WILL need something to prevent a CEL, you can either use a non-fouler to attempt to pull the o2 sensor out of the exhaust flow or you can use an electrical fix like the MIL to ensure you're sending back optimum readings all the time. Either way its your call.


I say buy a MIL and gut that pre-cat.