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So I've got this 94 F-150 with the 302. I was just wondering if anyone here has replaced the stock muffler with a straight pipe with leaving the stock cats on. Will it be really loud and raspy? Does anyone have a video if this setup? Any help is appreciated, thanks.
I have an 87 5.0L and I had the muffler shop "gut" the Catalytic Converter and run 3" into a 12" Small Diameter Glass Pack just past the rear axle and then dumped at a 45 degree angle. It sounds very good like a purring cat.
However, I am replacing the entire exhaust system with shorty headers and 2.5" tubing through a y-pipe then a Hi-Flow Cat without the air tube into an Enco Glass Pack and terminating at the rear bumper with a Stainless Steel tip.
It should sound even better and I will have more torque with the 2.5" tubing.
I cut of the muffler on my 96 with the 302 and you couldnt even hear it still. i ended up cutting off the rear cat and put a pipe i had on it and it was louder but not obnoxiously loud. it has quited down tho over the months not exactly sure why tho
With the cats still on there you can get rid of the muffler and run a piece of pipe where the muffler used to be and get a decent sound for cheap. I myself have cut off the second cat off gutted the first one and have a three inch piece of pipe dumping under the bed and its loud as heck and sounds like a demon but no cops have pulled me yet. With the cats intact it won't be to loud and in my opinion it didn't sound to bad to my ears. If you want I can post a link to my before and after of the cats, it two difference videos but it should give you an idea of what it sounds like.
Thanks for the responses. Unfortunately I live in California so the cats have to stay on. So if I did take the muffler off, is there a change in sound at all? Also what length and diameter is the muffler so I can buy a straight pipe? Videos are appreciated, thanks.
The pipe size should be 2 1/4 and you can get it an places like auto-zone for a decent price. Its not a huge difference but I will say it is a noticeable improvement over stock.
This is the straight pipe with no cats.
mind you the second one says straight pipe but it still has the cats on there and intact. Let me know how it goes for you and if you can post your own video of your setup as well as I'd like to see how you went about it.
Thanks for the responses. Unfortunately I live in California so the cats have to stay on. So if I did take the muffler off, is there a change in sound at all? Also what length and diameter is the muffler so I can buy a straight pipe? Videos are appreciated, thanks.
Hello and good afternoon Steve.
I lived in California for 50+ years and this is what I did to my VW Fox.
I had the muffler shop make a spacer the exact same length as the Cat secured with standard muffler clamps.
I would put the cat in, pass inspection, then when I got home I would take off the cat (2 in your case) and simply install the spacer.
It is quite simple and I gained 3-4 mpg but this was on a "four-banger".
They should not say anything as all that is required is that you have cats installed.
A bit devious but oh well.
Take care
Boon
P.S. It is important that you change your oil just prior to testing and have no more than 1/2 tank of fuel. Your results will come out better. I know exactly how California works when it comes to testing. I moved to Missouri in 2009 but at that time they were still checking gas caps!
So I've got this 94 F-150 with the 302. I was just wondering if anyone here has replaced the stock muffler with a straight pipe with leaving the stock cats on. Will it be really loud and raspy? Does anyone have a video if this setup? Any help is appreciated, thanks.
Hello Steve.
Look at my reply above.
It is then that you mentioned California. It is very important that we provide at least a general locale where we reside; at least the state and more importantly, the description of the vehicle; year, model,engine size, 2 or 4 wheel drive, transmission, and any modifications.
With the cats still on there you can get rid of the muffler and run a piece of pipe where the muffler used to be and get a decent sound for cheap. I myself have cut off the second cat off gutted the first one and have a three inch piece of pipe dumping under the bed and its loud as heck and sounds like a demon but no cops have pulled me yet. With the cats intact it won't be to loud and in my opinion it didn't sound to bad to my ears. If you want I can post a link to my before and after of the cats, it two difference videos but it should give you an idea of what it sounds like.
does gutting the first cat after removing the second cat and muffler make it noticeably louder? I have the same set up as you except i havent gutted the first cat and im just curious if its worth it?
It does make a big difference in sound, I've had people say they can hear me coming a good half mile down the road if I'm getting on the gas real hard. If you live out in a more rural area and don't do much driving in the city then I say go for it with gutted cats and no muffler but if you are in the city at least put a glasspack in there, not a long one but just enough to knock the edge off it otherwise you'll be seeing allot of tickets for noise violation.
Also another thing to note is if you have both cats gutted you can if you so want to can get rid of the smog pump and the tube that runs to the back of the head and clean up the engine bay but that might push your luck when it comes inspection time.