I have a 97 f250 hd 5.8 351 4wd duel exhaust, it sounds ok right now but i want to make it louder and iam cheap at the moment. I was thinkin of removing the cat(only 1) because its bolt on but rusted in place lol, i was wondering if anyone has ever done this and what is expected as in sound. I know its gonna be louder when removed but is it gonna be so loud that i put the cat back on or is it gonna be little more beefy which is what iam going for or should i just buy a performance cat or muffler. I got time to kill and theres nothing wrong with the engine lol so i need something ur opinion's would be very helpful thnx in advanced.

 

Cats like you have are not like the early designs of the 70s and 80s. They do flow decently, but with age and mileage yours could be about ready to be replaced.

Normally when the cats come off, you notice some higher frequency tones and I think they sound tinny. Also, you notice a little bit of an egg smell from the exhaust. Add to that, it's illegal and I don't think it's worth it.

I take it that you've already removed the mufflers? add a set of cherry bomb or glass pack mufflers to remove the high frequency sounds, then reduce the size of the pipe. Just for an experiment, hold a piece of 4" PVC over your mouth and yell down it, then do the same thing with a piece of 2".

 

I havent touched anything on the exhaust just yet shopping around for opinion's gettin ideas. I only have one muffler so i dont know if i have tru duel exhaust, 2 pipes from the manifolds go into cat one goes into the muffler and then 2 come out of the muffler and out the side of the truck

--l``````l----[muffler] _-_-_-_-_-_
--l_Cat__l

like my pic rofl

which one do i replace to make it sound better and wut would i get 150$ spend should be enought ehh .

 

I'd just replace the muffler with something from Magnaflow, borla, Dynomax or flowmaster. Replacing the muffler alone should run you under $100 and will significantly change the sound of your exhaust.

 

Alright sweet thnx for ur time and help reax i apreaciate it iam gonna start looking for a muffler cuz iam bored as all hell lol thnx again

 

Alright well i bought and installed flowmaster muffler 40 series and it sounds better then u thought it would has that hot rumble to it. Figured i put up alittle update, gonna do mass air next. If anyone got any ideas on that plz toss em this way.

 

If you don't have to pass the sniffer test I'd put on a high flow aftermarket cat. The stock cat is more restrictive and kills more sound than an aftermarket cat high flow cat. If your talking about swapping out the MAF housing and sensor with a unit from granatelli and etc I highly doubt you will notice an increase in performance. Just make shure you keep your stock MAF clean, clean it at least once a year. Also a cold air or aftermarket intake won't make a noticeably power difference either. Just my $.02

 

Don't use a granatelli. If you must change it out, get a stock lightning MAF. Really the only reason to change the MAF is if your pinging the sensor. I had thought and researched through all of the MAF madness, and found I'd be better putting money in the drivetrain.

Once you start swapping the MAF, either the MAF must be calibrated to your vehicle or you must calibrate your vehicle to the MAF. The diameter is fixed, so the sensor is reading how much voltage is required to keep the sensor wires at a certain temperature. Once you change the diameter, you have changed the flow characteristics of that fixed space. Now either your ECM has to be informed that 1.2 volts means 32 cfm and not 28 cfm (I am just throwing out numbers.) or the sensor must be tricked into putting out 1.1v. Tricking the sensor is what granatelli did to work around this problem, and a lot of custom tuners noticed that what worked on one G-MAF didn't hold true on the next. They figured the sensors were not calibrated on a flow bench, which meant that their accuracy couldn't be trusted. It was a mess.

For non-supercharged motors, the lightning MAF will be all the upgrade you could want, and you probably couldn't feel or notice the difference with it.