Muffled 7.3 sound

[D66stroke]

Probably a waste of a thread, but does anyone run straight pipe yet the truck sounds muffled? My 97 has no exhaust note to it, no crackle, no nothing. Just curious because my previous 97 with full 4" sounded amazing from in the cab, the one I have now I've tried full 4", 5", now axle dump and nothing's changed lol. Meanwhile every 7.3 I've rode in/drove with straight pipe (no stacks, no side exit) sounded really good. Now I will say I have a T4 mount and 366 (.91 housing) so not sure if that turbo in particular would quiet it down, but even with the stock turbo it just seemed abnormally quiet, yet louder than with the 366

 

[joe d]

My 366 is silent compared to stock

 

[joe d]

All intake noise

 

[D66stroke]

Yup same here, all whistle under the hood, but it's not enough noise to overcome the sound of the exhaust when the windows are down. There's just simply no exhaust note compared to the stock turbo. I'm wondering if it has anything to do with a smaller exhaust housing? Like the .91 on the 66 compared to the 1.15 on the stock turbos?

 

[DEEZUZ]

You might want to dump it to the ground. Will get a nice thump then

 

[joe d]

I liked my turbo whistle. But it sounds good when you dig deep. But no whistle at all

 

[D66stroke]

It's currently dumped to the ground and sounds no different or any louder than before lol

 

[joe d]

Do you have. 300/100 or 300/200 sigs confusing?
What boost do you see are you gated? Do you moniter back pressure if so whats it like thanks joe

 

[gnxtc2]

BASB and 5" straight piped.....turbo whistle and throaty. Quiet at idle but throaty when passing a semi.

Billy T.
[email protected]

 

[D66stroke]

Do you have. 300/100 or 300/200 sigs confusing?
What boost do you see are you gated? Do you moniter back pressure if so whats it like thanks joe

300/100's. I originally had my injectors built to 180/100's, then soon after had them build me hybrids. I was gonna go 300/200's but at the time didn't have the T4 mount so wanted to hold fuel back as much as possible, and figured 300/100's should get me to surpass 500 rear wheel which I'm happy with for a daily..

Not gated and don't have a boost gauge, just egt and trans.. I have a Edge CS monitor so I guess I can monitor back pressure, is there any particular numbers/readings I'm looking for?

 

[D66stroke]

BASB and 5" straight piped.....turbo whistle and throaty. Quiet at idle but throaty when passing a semi.

Billy T.
[email protected]

I feel dumb, I have a decently modded 7.3 and I'm over here worried about how it sounds lol.. Do you think 366's and/or smaller exhaust housings quiet down our trucks?

 

[D66stroke]

So exhaust backpressure was between 4-6 depending whether I was idling or driving. Not sure if that's good or not

 

[joe d]

So exhaust backpressure was between 4-6 depending whether I was idling or driving. Not sure if that's good or not

What was it at at like 40 psi boost.

 

[D66stroke]

Again no boost gauge, and PCM only reads to like 22psi I believe so my monitor is no help for that. But it seemed no matter how hard I got on it, it didn't go above 6

 

[joe d]

Must have clogged ebp sensor or tube. Or wrre you pulling from the up pipe or manafold with a mechanical gauge.

 

[D66stroke]

Through the PCM. I'm about to run to work in a little, I'll get on it real good and see what happens. I did notice 2 codes for EBP sensor or something, but my truck runs like a raped ape so I don't know

 

[D66stroke]

I've had a cam sensor code since I bought the truck 2 years ago but didn't think much of it because I always thought a bad cam sensor will cause the truck to randomly stall which it never did. Yesterday I took the truck to my injector builder and he did a buzz and cylinder contribution test, all checked out good.. He told me how a bad cam sensor changes timing so I put one in and sure enough my 7.3 sounds like a 7.3 again, and idles much smoother. Not as much clatter coming from the injectors while driving and it's actually louder out the exhaust.. Despite the tests checking out good there were still codes for cylinders 3, 6, and 7.. So I'm gonna pull them and have him cut them down to 238's while he sees whats wrong with those other 3 injectors

 

[Plzstrokeme]

Little off topic but how do you like your s366? I am going to be running one soon with 160/30s and your one of the few people I have noticed running one on a 7.3

 

[joe d]

I dont know if that was directed towars me but i love mine with my 238/100 it spools amazing and runs good its a good dd setup in my opinion. But with that being said i have heard other people say they felt the s366 was a turd. But if i was a beting man id say they had other issues as ro why they felt it didnt spool well good luck.

On edit there is a new s369 out im hearing great things about and that would leave tou room to grow.

 

[Plzstrokeme]

I am happy you like yours. I have been told my injectors may be too small for it. I have had this turbo sitting on a shelf for a year now that I bought from the classifieds brand new for 500. If I don't like it I guess I will look into something else. I think it's gonna be a step up from the d66 and leaky up pipes I am running right now. Hopefully my t4 kit will be on its way soon.

Sorry for the derail.