7.3 Powerstroke question

[Ouachita]

I bought a '99 single wheel one ton and getting ready to put taller tires on it.

The truck has a new exhaust system on it, but the previous owner removed the muffler. The shop must have measured once and cut twice, because there is only one inch between the tire and exhaust pipe.

I'll need to increase that clearance. Easiest/cheapest way is to add a length of straight pipe, but it wouldn't bother me if the truck was quieter.

This rig has been "tuned" or "programmed", whatever it's called, and I love it. It gets 26mpg empty on the highway.

Question- Will installing an OEM type muffler effect the tuning? In other words, if I have a muffler installed, should I expect different performance, or have to re-tune?

 

[chevytaHOE5674]

You won't notice anything except less noise.

 

[Ouachita]

It appears to me that many of these trucks have a "straight pipe", so a separate but related question; Do people do this for a performance advantage or just because it sounds cool?

 

[Ouachita]

You won't notice anything except less noise.

That's what I was hoping. Thank you.

 

[sstterry]

It appears to me that many of these trucks have a "straight pipe", so a separate but related question; Do people do this for a performance advantage or just because it sounds cool?

Do you know if it has a stock exhaust on it now? Changing the size can affect back pressure. But I would listen to Chevy if you are only adding straight pipe and nothing else.

 

[Ouachita]

These tires are 31" diameter. I'm wanting 33", maybe taller if I can get them without going much wider.

 

[Ouachita]

Do you know if it has a stock exhaust on it now? Changing the size can affect back pressure. But I would listen to Chevy if you are only adding straight pipe and nothing else.

I'm needing to lengthen the exhaust to have clearance for taller tires. I can do that by just lengthening the existing straight pipe, or by adding a muffler back into the system.

I'd like to add a muffler if it won't effect the way the sensors signal the powerplant (I don't want to change the tuning…….it's perfect)

 

[sstterry]

I'd like to add a muffler if it won't effect the way the sensors signal the powerplant (I don't want to change the tuning…….it's perfect)

I would definitely ask an expert on tuning about adding the muffler. Reducing airflow on a tuned truck can affect performance if it decreases airflow.

 

[kenny thomas]

Some of the reason for straight pipe vs a muffler is a huge price for the muffler.

 

[simme]

I have a 96 7.3 and I don't get anywhere close to 26 mpg. Might should leave that exhaust and tires just as they are.

 

[Ouachita]

I would definitely ask an expert on tuning about adding the muffler. Reducing airflow on a tuned truck can affect performance if it decreases airflow.

I thought everyone on the internet was an expert

I think there are folks here who can help guide me to a decision, and I appreciate the value of what I pay for

 

[Ouachita]

I have a 96 7.3 and I don't get anywhere close to 26 mpg. Might should leave that exhaust and tires just as they are.

25.8 according to the mileage display thingy, and confirmed to be very close when tracking miles and gallons added.

This is running empty on highway. I haven't pulled/hauled anything with it yet.

 

[Ouachita]

Some of the reason for straight pipe vs a muffler is a huge price for the muffler.

I haven't priced one yet. That detail may influence my decision. What should I expect to pay for a "quiet" muffler?

 

[simme]

Generally, the higher off the ground, the lower the mileage.

 

[kenny thomas]

I haven't priced one yet. That detail may influence my decision. What should I expect to pay for a "quiet" muffler?

The reason my Dodge has straight pipe is a $300+ muffler.

 

[Warren Allison]

I bought a '99 single wheel one ton and getting ready to put taller tires on it.

The truck has a new exhaust system on it, but the previous owner removed the muffler. The shop must have measured once and cut twice, because there is only one inch between the tire and exhaust pipe.

I'll need to increase that clearance. Easiest/cheapest way is to add a length of straight pipe, but it wouldn't bother me if the truck was quieter.

This rig has been "tuned" or "programmed", whatever it's called, and I love it. It gets 26mpg empty on the highway.

Question- Will installing an OEM type muffler effect the tuning? In other words, if I have a muffler installed, should I expect different performance, or have to re-tune?

I had the same thing, 99 F350 single wheel, and it got 26 mpg, but it was a 6 speed manual. Do you know what programmer you have? Most popular one for those were the Bullydog. I had that programmer and the truck had its stock exhaust system.

 

[Ouachita]

Mine is a 6 speed manual. I don't think what I have is a "programmer" (I can't change anything, only observe the parameters).
My understanding is, if I want to change the tuning, I'll need to have someone smarter than me hook up a computer/programmer.

 

[Ouachita]

I had the same thing, 99 F350 single wheel, and it got 26 mpg, but it was a 6 speed manual. Do you know what programmer you have? Most popular one for those were the Bullydog. I had that programmer and the truck had its stock exhaust system.

This is the display

 

[Warren Allison]

This is the display
View attachment 28973

Does it plug into the diagnostic port under the dash? You got a single cab, extra cab or crew cab? Is it 4wd?

 

[chevytaHOE5674]

There are no sensors that will be effected by adding a muffler. Guys straight pipe them for the sound. Could it possibly increase EGT's running a muffler? Yes. But my experience is EGTs aren't typically a problem.

My 7.3 is running aftermarket fuel injectors, lift pump, programmer, and bigger turbo all running thru a muffler to keep it "quiet". I've never had to get out of the pedal because of EGT's.

Either add pipe or a muffler to get the tailpipe away from the tire. Either solution won't change a thing.