I've got a 1992 Ford F350 4x4 with a 7.3 L IDI Diesel engine in it. And I was wondering if I straight piped it what it would do? And would it sound better? And what do you do when you straight pipe it? And also this is a stupid question but what is a cat?

 

A cat is a catalytic converter. Essentially cleaner air. I dunno if older model diesels have them.

Straight piping means louuudddd. No muffling items, since mufflers,resonators, cats and etc have been replaced with a straight piece of pipe. To give you an idea, I just put exhaust on my truck and it once was earlier today quieter than a minivan, now it rattles the houses nearby. I removed the two cats and muffler and ran dual pipes off, one for each manifold with a rear tire exit.

Straight piping is as simple as cutting off muffler or the like and welding on a piece of straight pipe.

Or hack sawing and clamping for the poe folk.

 

Thanks man. Should I do it?

 

Depending on how it sounds, I know some Gas engines that are straight piped' make this

loud crackling noise that doesn't even sound like an engine but with a diesel Im not sure, I

bet it would sound insanely awesome like most diesel's do. I would go for it.

 

Sure, as long as you hate your neighbors and don't mind pissing everyone around you off. And oh yeah, if you want your truck to run like crap, then yeah, go right ahead!

 

Yeah I've heard some of those gas one and they sound like ****
But I'll probably do it

 

What will the advantage's be and how do I pass inspection?

 

I always get better gas mileauge with my setups.
As I get older, they get too loud for me.
What kind of inspections? If visual only then gut the cats out and put them back. If sniffer test, than leave them or buy some hi-flo cats.

I suggest a large single full exhaust. That or smaller duals with a crossover but a single is really best IMO. I run a single on my high performance Firebird to give you an idea.

 

Cool thanks

 

What is better a the 7.3 or the newer 6.7

 

Better for what? A newer 6.7 produces more power but costs way more than you're old 7.3.
Anyway, I'm going to assume your truck doesn't have a turbo, but I'm going to explain both ways anyway. If you have an N/A truck (no turbo) it is going to crack like nothing you've ever heard. It is absolutely ungodly loud and you will hate every second of it. My uncle used to have one that my other uncle straight piped for him because they thought it would be cool. He drove it once and put mufflers on it because he couldn't turn up his radio loud enough to drown it out.
With a turbo its not going to be so loud as long as it's under the turbo. But it'll be slightly louder when the turbo isn't spooled up, which is at lower rpms so its not so bad.
In any case, the further back you lead the pipe, the quieter it'll be in the cab. And the bigger the pipe you use, the deeper crack it will have, and if you use 2.25" pipe like my uncle put on that truck (it was dual exhaust) it will be worse. You're better off with a muffler, especially if you get inspected. If you try to get that inspected with no exhaust components there...well good luck.

 

Just a warning from a fellow straightpiped 7.3IDI owner, if you hate the cackle/rasp/jackhammer (whatever in the world you want to call it) sound that you also get from a straightpiped gasser you're going to want to run a muffler of some kind on your IDI. The N/A 7.3 will cackle way more than a gasser does. If your motor has a turbo that cuts some of it out of there, and running bigger pipe also helps.

 

hahahaha see my signature line!

 

Sure! If you like getting pulled over by the cops and paying tickets all the time. And if you like paying impound fees. Oh, and being illegal enough to get arrested should you be pulled over by a Federal cop on Federal land.

 

Gas motors straight piped dont sound good, but a diesel straight piped as long as it 4 inch or maybe 3 inch piping minimum, it should sound beast!