Engine/Transmission (1998.5 - 2002) check out my revised downpipe design

[Forrest Nearing]

reduced resonance quite a bit... the exhaust note is a little more subdued, but still got a nice powerful tone. I wish it didn't eat up so much turbine whistle from the exhaust note, but the straight pipe was killing me... I've been logging 500+ miles a week, and I couldn't cruise over 70mph comfortably... 75mph is fine now. I might throw the 5" muffler on it, and see just how quiet it is then!



you're looking at a 4" dynomax bullet (5" OD). It's sucked up so close to the turbo, that it's still 4" pipe by the bellhousing and frame rail, so it didn't effect clearance at all.



I figured the added mass would help interior resonance that seemed to be coming from the engine bay. I laid lead sheet all over the interior, but wasn't able to cover the firewall as much as I would have liked.



Forrest

 

[Forrest Nearing]

another angle

 

[ToolManTimTaylor]

WHOAH Way to go Forrest! Pretty slick!



Goin' to move this into the 2Nd gen Engine discussion area.

 

[Forrest Nearing]

I threw the 5" muffler on...



man, I wonder what kind of hearing damage I've been doing to myself... the turbo is LOUD!! it's all you can hear... 80mph is no biggie. as far as resonance (that's where it has always been at its worst)



I'm tempted to install the silencer ring to see how quiet it'll be, but I'm affraid I may fall asleep at the wheel!



not sure if I'm gonna be able to leave the muffler on... I like the lack of resonance, but the exhaust note is just plain quiet



Forrest

 

[ToolManTimTaylor]

Yeah but it may only be quiet to YOU! Lemmie explain kinda. Have someone drive away (And hopefully return) In your truck and take note of the exhaust ... Note. The dynamics of the sound may not be detectable inside the cab? My Mustang sounds ehhh O. K when I am driving it. But stand behind it and give it a stab and WHOAH that thing sounds angry.

 

[Forrest Nearing]

well... I definately know what you mean... my fairmont sounded absolutely wicked on the dyno!



I was about to ditch the muffler again, but decided if I wasn't going to get to hear the turbo spooling down through the exhaust, I might as well keep it quiet.



I popped the silencer ring in. just out and out too quiet... might put it in for a long haul, but man, I gotta have SOMETHING to listen to!!



yeah, I know what you mean about hearing it from the outside, but I guess I'll never know because nobody drives my truck but ME!



Forrest

 

[Smokin Joes 2500]

you guys and your ford cars??

I did like Tool Man said I had my buddy drive my truck while I followed him and JEEZ does that thing whistle. Ive never heard it before (4" straight pipe) I love the noise guess its cause Im young! But put my son in the back and hes asleep in 5 min. I think hed rather the Dodge sing him to sleep than my wife... .come to think of it Id rather that too.



P. S. Id put my 85 Olds Cutlass up next to anyMustang or Fairmont on here

 

[Forrest Nearing]

I love the sound of a straight piped Cummins, and I'm only 26... my old truck was no biggie... I put over 100k on it all straight piped, but this thing is a totally different animal for some reason...



it's kinda lame now, but maybe my ears won't ring when I get out of the truck after 3-4hrs in the seat...



on a positive note, that 6 blade HX40 compressor wheel sounds kick ass on the highway... I think I've turned more heads with the muffled exhaust than with the straight pipe (because the turbo is all you hear now, and people look over expecting to see an 18 wheeler next to them! )



Forrest

 

[Forrest Nearing]

Re: you guys and your ford cars??

Originally posted by smokin joes 400



P. S. Id put my 85 Olds Cutlass up next to anyMustang or Fairmont on here

whatya got in the Cutlass? my fairmont did 328/329 on the dyno on 87 octane... car weighed ~2850lbs w/ AC and 17" wheels



now it's getting put back together with a weak-nut stock motor (had to sell the drivetrain to help pay for the truck!) the 4. 30's were replaced with 3. 08's, etc. oh well, at least I've still got it...



my old Fairmont wagon went high 11's NA on 87 octane.



I've got a buddy w/ a LS1 powered Fairmont wagon that runs deep 9's on a 150 dry shot



Forrest

 

[2ndgen2500]

thats a really sweet setup, wish i had the tools to create such items... .

 

[Smokin Joes 2500]

Re: Re: you guys and your ford cars??

Originally posted by Forrest Nearing

whatya got in the Cutlass? my fairmont did 328/329 on the dyno on 87 octane... car weighed ~2850lbs w/ AC and 17" wheels



The Cutlass is crazy! Granted Ive dumped a ton of money in it! Its got a 377 inch small block pushing the 650 horse barrier. Dart Pro 1 heads professionally ported, carillo rods ross pistons complete comp cams poller valve train etc. It runs 9. 80s in a fairly heavy car. Its fun, like somebody strapped me to a rocket!!! peace my man

 

[Forrest Nearing]

sounds pretty wicked! what's the curb weight on that pig?



Forrest

 

[juicedcummins]

Forrest I tried that same muffler on my original set-up. It was up against the down pipe and worked well for about 1year. Then on a long haul maxed out, it slowly got louder and louder and the drone came back. If you pull heavy it wont last. Check out the specs on the muffler and it is only rated for 1200deg. [from top of head ,dynomax books have good info. ]

I now run a heavy truck muffler in the same spot with Zero drone and tons of whistle outside.



Your install does look nice and clean.

 

[Forrest Nearing]

yeah, I was wondering about that... oh well, if it burns up, hopefully the added mass on the downpipe will help keep resonance at bay...



we'll see how it goes I guess...



Forrest

 

[Hemiless]

what muffler do you run

juicedcummins



What muffler are you currently running? Do you still have one mount back in the stock location? How much quieter did it make your truck?



I've been looking at doing some exhaust work on my 02 Quad cab when I install my exhaust break so I'm just trying to get accumulate some different suggestions and ideas before I start. The goal is quite without robbing power or raising EGTs.



Any info on your set up would be great.

 

[Forrest Nearing]

the muffler is a 5" job from City Muffler... inside the truck with the passenger side window down, I can barely hear the exhaust note reflecting off of walls... it's VERY quiet... zero impact in flow or EGT over straight pipe.



Forrest

 

[darkhorse]

Nathan, I just installed a Banks Brake with their 4" exhaust. Even with the straight through muffler, I don't notice any increase in noise in the cab.



Richard