mack b-61

[jfh]

Hi , i got my air tank for my mack . but here is what i am wondering what harm is it going to be for me to run this classic diesel with straight exhaust. i have been trying to get another muffler like it came with in 64. it had the the one that came on it when it was new, everyone seems to have it on factory back order. so i was going to run it straight , i have had other diesels that were that way, and seen a good many classic macks with the exhaust straight. what i am wanting to make sure is that i don't want to end up tearing my mack up in the long run . thanks in advance for any help

 

[chiefrunamuk]

jfh; B-61 MACK 1960 was my 2nd truck, ran a straight pipe on it for 3 years, only thing that happened was broke a head bolt; course that was my fault,had it cranked to 2400 hundred R.P.M.and had the fuel turned up, ran like a striped a$$ ape. KEN

 

[Anonymous-0]

You will hurt nothing. Most early Turboed Diesels had straight thru exhaust Pipes.all the Muffler does on a B61 is allow it to pass the noise Laws. Those Mufflers were nothing special,have you tried a scrap yard? my B61 had a muffler which was just like ones on whites,IHC,Reo's etc. My B75 had a Turbo on a Cummins 250 and it had two straight Pipes. My KW 100 had a Turbo and two straight Pipes also. Some of these Operators here in Az. run 8" Twin Stacks with no Muffler and no one seems to bother them. Goe to an Antique Truck or the Mack Site and take a look at some of the Old Timers featured there. Not many of them have Mufflers. I personally really like Straight Pipes. Especially after dark on a hard pull and you can get about two foot of fire out of the Pipes. "Just like Will & Sonny"

 

[Roy Suomi]

You can go to any NAPA store and request to look at their Heavy Truck Exhaust book..That book either has a listing or sizes[ lengths , pipe sizes , inlet and outlet diagrams]...On my Mack RD-690-P single axle truck , it's got a 4" inlet and a 5" outlet..Whats with that???? Big oval muffler under the cab with a stack up the right side...I used to drive carry-all for Mahnen Machinery years ago..When they sold the Mack tractor there , they came up with a Pete conventional 8V71 with Quadraplex trans..On the break-in trip to the other store the elbow next to the drivers door rotted off , door weatherstripping was gone and the heater motor was smoking profusely..After that trip , I was glad to have a quiet truck to drive...

 

[Anonymous-0]

Bet you pulled some Fire from the Stack , can see it now.