2nd Gen Non-Engine/Transmission 5" exhaust overkill?

[CHolman]

SEM PER FI, didn't know we had other Marines at the TDR :-laf

I just left cherry point in Jan... I drove the Silver 04 dually with 6 inch stacks and power wagon decals... Lot's of goodies to make it sound cool...

 

[WDixon27]

i have the rip rook 4" duals without a muffler and like them, a little loud after 14# of boost but not enough to make me mufflerize it :-laf

 

[Kiohio]

Wdixon do the duals have a drone?



KO

 

[WDixon27]

nothing really annoying maybe a little buzz 2000-2100 depending on load, i haven't really done any heavy towing with them, i did dolly a extra cab 4wd nissan about 70 miles it didn't bring up any annoying harmonics

Wdixon do the duals have a drone?



KO

 

[DMoon]

Thanks for the replies everyone - and a big Oohrah to my dysfunctional brothers out there :-laf







I don't think I could quite do stacks right now - for those not in the military, our pay pretty much sucks, and I would feel quite dumb driving around with stack/s and nothing to back them up... . some day, though... .

I guess in the end anything is better than stock (or what's left of it) - at least there wouldn't be any downsides to going 5" - it'll kind of depend on how much I can manage to spend/blow on it. I'm leaning towards MBRP; haven't heard anything bad about them, and so far everyone seems pretty happy.

OPoole - it seems like there's a ton of space under the truck, but maybe I'll mock up something with cardboard tubes or whatever to see how large it might be. If people can fit 6", I should be able to manage to wedge in 5".

I just installed the MBRP 4" exhaust on my '95, otherwise stock CTD. Luv the sound and throttle response (turbo spool up) was a little better. Fuel mileage increase??? Not notable but then again my fuel mileage isn't bad for what I got. 18-20 MPG

Having BD 40 HP injectors installed today and can't wait to see how it runs. Next on the lst an aFe intake system, fix the old KDP issue and perhaps bump the fuel up slightly. Don' think I'd do much more because I don't want to spend big $$$$ on transmission upgrade

 

[ANicklas]

I'm not really expecting much of an improvement with fuel mileage - mine's pretty bad (avg 15-16), but then again I have a relatively heavy truck (4x4, quad cab, long bed) and 4. 10s, and I tend to hammer it a bit. On the other hand, knowing I only gave up four mpg moving up from my anemic s-10 (2. 2l, auto, 4x2), it really doesn't seem that bad.

 

[Gary - K7GLD]

Here's a 4 incher at the spare tire - a 285 - I finally made an aluminum "sandwich" to protect the tire from heat.



#ad




5 inch - Hell, just throw an 8 incher in there if it's primarily for show - it'll really impress the fart can Ricers...

 

[CochranD]

Around here , we call `em grapefruit launchers , on the ricers

 

[KyleAnd]

I just put an MBRP 5" aluminized on my QC SWB and love it. Took about 3 hrs to tear out the old one and get the new one in. The kit goes together real nice and I had plenty of room around the spare. Faster turbo spool, a little louder (moreso at 75 mph), lots of compliments, and a whole lot funner to drive. If you would like to see some picks email me and I will get them for you.



Kyle

 

[IanF]

Regret is such a strong word! I have a 4in straight. I like it. But it is loud. The draw back is towing my 5er and pulling a big hill. There is a definate drone in the cab. It gets Loud! I have thought about putting in a muffler but I just like it too much when the truck is empty. I picked up about 1mpg and the turbo spooled much faster. I think that is worth the increased volume.

My '95 came with a S. S. 4" system with no muffler. It was loud. Too loud for the residential area I live in. So I installed a muffler... better, but still a bit loud...



Oddly enough, I don't notice it in the cab (even before the muffler), but when leaving for work early in the morning, I try to be gentle on the go-pedal... one of my co-workers claims he can still hear me accelerating 1/4 mile from the office... :-laf



I've kinda grown to like the sound, but if/when the time comes, I'll probably replace it with a stock system.

 

[Big Rich 01]

i have 5'' on mine. the key is to make sure it dosent hit any other parts of the truck. this will only amplify the drone. mine has it around 2100. thats also about 85 mph. cruising no drone. 60-75 mph 1900rpm. sounds great. all in all i would do it again

 

[BTilson317]

Go with 5"

% all the way, i think 4" is for the more "raspy" sound, sorry guys i never was a fan of the 4". I've got a 5" and the Drone is there around 2000rpm but the sound of 5" next to a semi or a big wall ccannnt be beat guys. All in all it's a good deep tone.

 

[WDixon27]

i think i missed out on the raspyness on my 4" with the duals, a lot of cummins pass by infront of my shop and i get to hear them and i just about had a sonic drag with a 4" straight piped 3rd gen while stuck in traffic a while back and mine kinda sounds like a cross between stacks and a 5"

% all the way, i think 4" is for the more "raspy" sound, sorry guys i never was a fan of the 4". I've got a 5" and the Drone is there around 2000rpm but the sound of 5" next to a semi or a big wall ccannnt be beat guys. All in all it's a good deep tone.

 

[Hammer]

On My Mildly tuned 12v the 5" system cost me 13hp and raised my torque over 100 ft lbs in cold weather. The problem is without twins the exhaust cools to fast to exit the pipe efficiently by itself and the turbo works harder to exit the gasses,thus raising the torque and hurting the HP.



I was told this by a very respectable TDR member,who was a Coast Guard instructor for these motors for over 30 years. Myself,being hard headed and not one who listens very well,argued that he was wrong and later in the year at our fall dyno show I ate a huge plate full of overcooked crow. I had made no changes to my truck performance wise,ran the same amount of additive and came up 13 hp short and 125 ft lbs higher.



Yes the 5" sure looks cool and can be made into one of those Cali style "Grapefruit Launchers" but realistically save your extra cash and buy a 4" its all you'll ever need unless your planning on twins down the road..... Andy



BTW... .

All the 5" exhaust systems I have ever seen or installed are 4" downpipes and then enlarge to 5" at the intermediate pipe at the transmission due to clearance issues with the firewall.

 

[ANicklas]

Stacks!

Well I bit the bullet and decided I needed some sewer pipes sticking out of my bed.

I figured this truck was what I had wanted forever, so why not indulge the little-kid fantasy I've always had to drive something with stacks?

The exhaust needed to be done anyway (whole purpose for this thread), and a vision came to me while at work one day - I think it was Clessie Cummins himself - I needed stacks.

I called Olee Poole at powerbypoole.com and he set me up with some Grand Rock 5" slash cut chrome pipes, along with 4" piping from the turbo back.

Of course it cost way more than I intended to spend, but pretty reasonable considering the project :-laf.

For now, I have the Y-pipe of the stacks connected to the stock system and resonator since I didn't have access to welding equipment to remount the factory support. It definitely sounds great though . I think my fuel mileage is down a bit from hammering it all the time. My friends say it sounds like an 18-wheeler :-laf.

Soon (hopefully tomorrow) I'll be able to take off the factory system and replace it with the 4".



Next project - smoke to fill my new stacks.

 

[DShore]

I have 5" exhaust turbo back and yes, it has 4" downpipe. Works good, sounds good, and looks good. I had a drone about 2100 rpm... pulled everything out of the inside of the cab (including headliner) sprayed sound deadener plus 5/16" heat shield mat... still had the drone, but much, much decreased. Then installed Donaldson M090535 muffler. Still had slight drone, but it moved the rpm band where it shows up. Now drone is at 1600 rpm... don't spend much time at that rpm. Cruise at 70 mph/ 2100 rpm quieter than stock on the inside.

 

[kenny61]

Us Jar Heads are everywhere!!!!! Semper Fi and good luck with the truck.

 

[JFulford]

Dshore,

Where did you get the Donaldson Muffler? I'd like to get one but it looks like the Ryder place requires a business account. I'm just a peasant.

jeff

 

[DShore]

I ordered mine thru Ryder but just go to Google, type in "Donaldson" and the part number and there are multiple choices on several pages. Or, you can go to just about any over-the-road truck parts outlet or repair shop and I'm sure they have the Donaldson muffler listed. You might even check EBAY. Hope this helps.

 

[MGosciewski]

My '94 has a stock downpipe and 4" straight pipe back. Just added 181 delivery valves and a #5 plate. About to add 370 injectors. Should I upgrade to a 5" exhaust? Yeah, I know the trans is a concern, too!