Taking out the 4 cats

[socomboy]

What's up guy's? I have a quick question. I had my flowmaster 40 installed and as you can image it is not nearly as aggressive as it should be because of the 4 factory cats. I'm going to put magnaflow high flow cats on but confused as to which model to buy. the 99005HM is a "rear" cat and the 99175HM is a "front cat. Which one should I buy or are both of these wrong? Thanks

 

[walnuts4x4]

I have dual flowmaster 40s with the rear two cats deleted and cut the Y and ran true duals and it sounds damn good... might be cheaper and easier for you

 

[KWT2000]

i have the rear cats deleted through a single glass pack with dual tail pipes... just waiting on the 4" black tips to finish it off... sounds great total investment is $180... also i dont think the high flow cats will give you what your lookin for and there not cheap

 

[socomboy]

so if i delete the rear cats will i have to buy new piping or will the muffler shop be able to make custom piping for me? since I already have one installed i was thinking about just running true dual. Hey walnuts4x4, how much did that run you?

 

[kentv6]

I had true duels with a x-pipe and two flowmasters and tips installed for $380.
It sounds great.

 

[Poppa Wheelie]

So with all these meth heads stealing cats, we Expedition drivers are lucky ours don't get pinched!! I have a big-old Flowmaster (can't remember which one) and I like the sound, but it does sound pretty constricted. One of these days I'll look at going with 2 hi-flow cats and true duals, or maybe just one really big pipe.

 

[socomboy]

I have a 98 5.4 so i'm guessing i'll have to remove my spare tire to run a true dual? Also any thoughts on the piping? can they make a custom pipe for the other idividual pipe at the shop?

 

[panda24619]

no you dont have to remove it. nvycrmn has his true duals with his 35 spare. so it's possible. im thinking about cutting my exhaust after the muffler. my pipe is bent from my axle hitting it out in the dunes. not sure wht it will do, but i wont have to hit the pipe.

 

[socomboy]

that's good to know then. so I guess a good estimate for cutting the existing y-pipe, runinng a new individual 2.5 inch pipe, and deleting rear cats should be about 150 -200 maybe give or take a little?

 

[walnuts4x4]

I dont remember the cost for my exhaust setup... but the pipe was just regular 2.5" pipe cut and welded in... as for running true duals with a spare it can be done just have to widen the space between the two tips or dumb both behind the same tire "like I did" or split them and put one behind each rear tire...

the price and skill of the shop is the only thing that will hinder your dream setup... some shops wont work on the pipe in front of the rear most Cats... i am running into that problem when I wanted to do headers... so best bet is drive to the shop and talk to them in person since they might just say no over the phone....

 

[socomboy]

I thought it over and maybe true dual is not for me. I was thinking of just deleting the rear cats and the resonators for a aggressive sound. Keep in mind my city checks emissions so the rear cats aren't monitored for mixture are they?

 

[KWT2000]

my city checks emissions also but in 95 and newer cars with OBDII they just check for codes and im not getting a CEL so im good... i couldnt get a shop to delete the rear cats so i did it myself

 

[99 Expy]

I just got my exhaust done on my 99 expy with 4.6 last weekend. Did it at a local muffler shop and they cut the muffler and put a Y in and ran duals 45 our the back with 3.5 inch stainless tips for 230. I Love the sound, it is very aggressive and I am disappointed I had the expy for 2 weeks without it. lol

 

[nvycrmn]

lets see some pics!

 

[socomboy]

Hey guys I live where they still put the "sniffer" up your pipe so if I deleted the rear cats would I fail the test?

 

[99 Expy]

Here are some pics I took the other day. I can get more if you would like. I will see if I can get a video some time this weekend if I don't work.

 

[nvycrmn]

the weather looks really nice there 99 expy. man i miss the midwest!