2H Diesel Exhaust Questions

[Tofudebeest]

Naturally aspirated 2H in a 60-series.
I have the old down pipe and a new flange gasket, and that's it.

Questions:
1) Should I stick with the 2 1/2" (I believe that what the stock line is) or upgrade to 3"?
2) If I upgrade, how far back towards the manifold do I (or should I) weld on the adaptor and begin the 3" section?
3) Straight pipe or muffler?
4) I know the EGTs will be lower w/o a muffler (a very good thing), but will it be obnoxiously loud in a parking garage?
5) If muffler, any CHEAP free-flow recommendations that will help with noise but not restrict flow too much? Magnaflow is NOT what I have in mind when I say "cheap". I'm talking about a $50-75 muffler.

 

[Tofudebeest]

Muffler shop in town quoted me:

2.5" with a silencer "cherry bomb" type of free-flow muffler, hung, out the door = $150-175, depending on how complicated the bend job (labor) would be.
upgrade to 3" = extra $50.

 

[marting]

The original pipe is more like 2,2"
With no turbo you should atlest have some type of muffler.

 

[Tofudebeest]

2.2", huh..will have to measure it this weekend...

I guess if you're right, it is the metric equivalent of a 2.5"...

I intend to go turbo at some point, but probably not soon, unless I happend to find one in a U-Pull it lot. So I guess some sort of muffler will be necessary.

 

[Henry James the 47th]

The stock exhaust is 2.25".

I have the 2H in my 47 series, non-turbo, and am running with a 2.5", using mandrel-bent aluminized steel tubes. It flows really well. I have a muffler that was sourced through Napa.

If you go with a turbo, the 2.5" size should be fine, and then you can ditch the muffler if you like. I wouldn't want to run non-turbo without a muffler.

 

[Tofudebeest]

That's cool.
Recall which NAPA muffler?

 

[Henry James the 47th]

I don't recall the part number - it is aluminized steel, 2.5" inlet and outlet, and is around 26" long, about 6" in diameter. They should be able to locate it in their database just from the description I would think...

 

[Tofudebeest]

They had many fitting this description, round and oval, centered or offset...all of them under $40. Sounds just right to me. They have 2.5" tubing, flex pipe, junction/adaptors...

May do this exhaust myself...

 

[Tapage]

I ran my Tencha years ago with NA 2H and 2.5" exaust ( not mandrel ) and a cherry .. let me search for the video in Youtube ..

YouTube - 4x4 Muddy Hill Climb Test PART 2 - CLUB 4X4 PANAMA

min 1 or so ..

 

[watrob]

I had a 2.5" stainless system with stainless muffler put on the 2H, only cost 200 odd dollars complete.

 

[Tapage]

Just a note .. you loose backpressure with the 2.5" exhaust in a NA 2H .. I can feel it after the 2.5" with only a cherry.

 

[Tofudebeest]

which is more optimal: more low-end torque from backpressure (flow restriction) or the lower EGTs from no restriction (less backpressure)???

 

[Tapage]

which is more optimal: more low-end torque from backpressure (flow restriction) or the lower EGTs from no restriction (less backpressure)???

with 4.56 and 33" 2.5" sound perfect to me .. coz the lowend that you could lost with the exhaust the R&P helps but note I never drive more than 500 km contious and don't like to go over 120 km/h ..