V10 Exhaust TOO LOUD - What to do? - Diesel Forum

grec-o-face · 10-26-2009, 11:03 AM

Here we go....

I've got no Cat and a custom Y-pipe.
I've just installed the largest muffler I could find. It's a Dynomax Super Turbo RV muffler (part number 17789). It's WAY too loud for me.
I was thinking about adding a glasspack to the system - running it in front of the muffler, where the cat would be. I just don't know if that will chill it out enough.
Does anyone have any recommendations here...? What the hell do I do?? What about a different muffler?
Thanks All

doczenith1 · 10-26-2009, 01:27 PM

What about picking up a stock muffler from the salvage yard and trying that?

grec-o-face · 10-26-2009, 01:39 PM

Quote:

Originally Posted by doczenith1

What about picking up a stock muffler from the salvage yard and trying that?

I had a stock muffler in there - and it was almost just as loud. So, I figured the Dynomax (being twice the size of the stocker) would quiet it down...

carringb · 10-28-2009, 02:50 AM

If I were you I'd put the cat back on. The engine is tuned for a mild amount of back-pressure. Without it, you are losing some low end torque. I suspect you will find the truck more responsive and will get better fuel economy with the cat installed.

I have the Banks muffler, and it makes a nice mellow burble without being intrusive.

grec-o-face · 10-28-2009, 07:59 AM

Quote:

Originally Posted by carringb

If I were you I'd put the cat back on. The engine is tuned for a mild amount of back-pressure. Without it, you are losing some low end torque. I suspect you will find the truck more responsive and will get better fuel economy with the cat installed.

I have the Banks muffler, and it makes a nice mellow burble without being intrusive.

It's just not an option anymore... unless I purchased a new one.
I actually removed the Cat and changed the Y-pipe - and GAINED mpgs with a custom tune from my dyno guy, (Pete Johnson - Concord, NH) I've gained more and driveability and throttle response is A+.
Carring, are you running a gasser?

carringb · 10-28-2009, 11:54 AM

Quote:

Originally Posted by grec-o-face

It's just not an option anymore... unless I purchased a new one.
I actually removed the Cat and changed the Y-pipe - and GAINED mpgs with a custom tune from my dyno guy, (Pete Johnson - Concord, NH) I've gained more and driveability and throttle response is A+.
Carring, are you running a gasser?

Yup. Same motor as you. I went with the full banks powerpack (long tube headers, y-pipe, muffler, tailpipe) and I'm running a diablo predator tuner. i have not custom dyno tuned it however. Just running one of the Predator's pre-loaded tune and then raised the shift points, rev limiter, speed limiter, and increased shift firmness.

Have you removed torque modulation? I've thought about it, but I'm wondering how important that is to transmission life.

I also have a Banks Ottomind chip I pulled out when I got the Predator. I'm considering trying to stack them, as they each help in different ways.

grec-o-face · 10-28-2009, 03:51 PM

Quote:

Originally Posted by carringb

Yup. Same motor as you. I went with the full banks powerpack (long tube headers, y-pipe, muffler, tailpipe) and I'm running a diablo predator tuner. i have not custom dyno tuned it however. Just running one of the Predator's pre-loaded tune and then raised the shift points, rev limiter, speed limiter, and increased shift firmness.

Have you removed torque modulation? I've thought about it, but I'm wondering how important that is to transmission life.

I also have a Banks Ottomind chip I pulled out when I got the Predator. I'm considering trying to stack them, as they each help in different ways.

Good news!!!
I just welded in a 20" glasspack directly in front of the Dynomax muffler. WAYYY Betterrrr!!!!!!!

I'm on a custom (emailed) tune from my dyno guy, but I havent been up to the dyno yet to dial it in, so I don't run WOT. If it's lean at all... BOOOM. I've done alot of tuning with the SCTs and Ford EFI, and I know it doesnt take much to blow a hole in a piston.
You should DEF get it onto a dyno for some wideband tuning.

carringb · 10-28-2009, 04:08 PM

I've had the tuner on for about 40,000 miles, and recently pulled the plugs. It appears it may run slightly lean occasionally, but not lean enough I'm worried about damage to the motor (it's got 260,000 miles and still like new).

Yeah, I'd like to dyno tune but there's not a lot of Predator dealers with a dyno that can take a 8,000 pound dually van. One of these days though... Especially if I add nitrous (yes... it can be done safely).

grec-o-face · 10-28-2009, 05:51 PM

Quote:

Originally Posted by carringb

I've had the tuner on for about 40,000 miles, and recently pulled the plugs. It appears it may run slightly lean occasionally, but not lean enough I'm worried about damage to the motor (it's got 260,000 miles and still like new).

Yeah, I'd like to dyno tune but there's not a lot of Predator dealers with a dyno that can take a 8,000 pound dually van. One of these days though... Especially if I add nitrous (yes... it can be done safely).

I hear ya, I imagine it would be tough to find a dyno that can handle that. - ide check withthe diesel preformance shops -
Oh, and I know Nitrous can be done safely... I'm not afraid of the sauce. Not at all!!!
Go for it man!