4 inch exhaust no muffler

[Cobra]

I have seen many threads questioning the hume or drone of the four inch exhaust without a muffler.

Just returned from Fla. From Pa to Fla and back and the noise level was quite acceptable. I ran mostly 2000 RPM with 3. 54 gears and it was comfortable. Occassionally getting up to 2300 RPM not bad. Over 2300 it was not real good but I could take it for atleast 30 minutes. No reason to go over 2300 as that was running faster than I wanted to. I did it just so I could report to those of you with the 4. 10 gears. That will give you some idea that when you want to run about 70 mph with 4. 10 it won't be awful.

Hope this helps.

 

[UKRugbyman77]

Sounds

Is there any of you guys out there that could attach a wav of what these 4" straight pipe w or w/o muffler/resonator sounds like? Anything would be nice, but an idle from the rear and then a little spool-up would be the best. Oo.

 

[radixr]

Straight Pipe

Rugbyman,



Shortly after I went to 4" straight pipes, I had occassion to drive over to my brother's house. His driveway is shielded by large pine trees so you can hear something approaching his house but can't see what it is. The driveway runs parallel to the house and the right side of the vehicle faces the house.



After I pulled in and started talking to him, he said that as I was coming up the driveway he was trying to remember why he had ordered a triaxle load of gravel! That's what a 4", straight-piped, Cummins sounds like!Oo. Oo. Oo.

 

[azcummins]

do you guys with the 4" strait - no muffler or resonator have problems with the turbo spolling up?

 

[Excessive Force]

4" STRAIGHT

My 4" exhaust starts at the turbo downpipe and ends about 3' behind the cab (5" stacks are next). No muffler... just the sweet sound of the CUMMINS. Sounds cool between shifts too !! No problem with turbo spool-up. Only pump tweeks currently.

 

[UKRugbyman77]

Oh gee thanks guys, especially radixr. Now I won't be able to get any sleep thinking about that sweet diesel sound - the way God INTENDED it to be heard. .

Are you straight pipers just going to the local muffler shop and telling them to fab a 4" exhaust from "x" to the rear fender, or what? What kind of green am I looking at spending with a 4" straight back??

 

[Excessive Force]

4" STRAIGHTPIPE

I kind of "cheated" . I bought a reducer fitting to go to 4" after the downpipe... ..... and used 4" flex-pipe to go around the transfer case... works great,and sounds sooooo sweet. Also dropped EGT by 100 degrees ! :--)

 

[Cobra]

straight pipes

UKRUGBYMAN77,

I took my truck to Advanced Diesel Technology. They are located nearby and are extremely competent. They are very nice guys and I think teir prices are comptetative. I can't tell you what the exhaust cost because I had other work done at the same time. If you would like to contact them www.smokindiesel.com for email and they belong to the TDR. For a PM it would be smokin ram.

Hope this helps.



Bill