Ford 7.3 turbo: exhaust too loud

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Just reasoned speculation on my part, but it seems if one has 4 inch exhaust all the way back, that just about all significant restriction would already be removed by the 4 inch forward pipe, even if a quiet stock muffler were retained.

The increased 4 inch pipe volume ahead of the muffler should be fairly sufficient to absorb the added hot exhaust expansion, especially at the low 100-200 hp boost levels usually attained by street trucks. By the time the muffler is reached, the exhaust is cooled and already contracted quite a bit. Once the exhaust gas is cooled, it no longer needs the volume it did while hot and, of course, the turbo power has already been extracted.

I'll bet there is very little dyno difference in 4 inch all the way back as opposed to half-back. Of course, if I were a truck accessory company, I wouldn't want to lose lucrative "plumbing" sales. As usual, there is more money in selling overkill.

So if the OP has an exhaust temp gauge, it would be interesting to see if downpipe temps don't remain about the same with no other changes except the muffler.

Wes
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Also try your cheap 2 cycle oil from walmart. This new ULSD doesnt have the lube propertys as the old diesel fuel. I use it and it does make a difference. Also if you have an open element air filter you will get drone from that to. You don't want the stock exhaust on a 7.3. They are so restrictive and makes for high EGT's when towing. Keep the 4" and just get a muffler. I have a 5" on mine and its only real loud when pulling a long grade.

I put 4" exhaust on mine and couldn't tell much difference except the tone was different

X2 on the Walker Big Truck Muffler.

BBURD wrote:
Thanks much fellas. I have been to sites for MBRP, SSDPro, etc. Right now, (having just bought the truck), I can't see 5-6-7 hundred dollars for whole system but less than 100 for muffler that will stop the 'drone' and quiet exhaust would be ok. Thanks for the help and references to products.

Perfect. Sounds like you have no muffler, add one and it will be fine.

Thanks much fellas. I have been to sites for MBRP, SSDPro, etc. Right now, (having just bought the truck), I can't see 5-6-7 hundred dollars for whole system but less than 100 for muffler that will stop the 'drone' and quiet exhaust would be ok. Thanks for the help and references to products.

I went with a Walker Big Truck muffler. It's a straight thru design. Dropped my exhaust temps 150*. Only slightly louder.
As others have said the 7.3L normally is louder than newer engines.

I agree. do some research on quiet mufflers for the 7.3. The drone is one reason I haven`t replaced the muffler on my V-10! when we do take our long trips I don`t want any offensive noise. the cold air intake can be bad under a heavy load (going uphill) but it only lasts at most 30 seconds. if it was for hundreds of miles it would`ve been removed!

I think the best you could do would be to have a stock exhaust system and muffler on it. When I tow for ten hours or so in a day I do not want any drone or additional noise at all.

Having owned a 2002 Powerstroke for over ten years, I have found the addition of a diesel fuel additive such as PowerService or something similar will quieten the engine a little.

Otherwise, there is not much you can do, IMO. They are very reliable engines but noisy.

The engine noise has gotten to be the sound of freedom to me and my wife, however!

Ok first you mentioned that the exhust has been modified and that it has a big tip.

Also as mentioned the 7.3 is loud and just like most diesels it has a uniqe sound all its own. If you want quiet then replace the modified exhaust with a stock system or do some investigation as I am sure that there will be aftermarket mufflers that will meet you and your DW expectations.

Good Luck