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| | | | Joined: Mar 2018 Posts: 40 Wrench Fetcher | | Wrench Fetcher Joined: Mar 2018 Posts: 40 | I have a C60, 1961, engine is a 235 per block number (possibly a replacement for what should have been a 261).
The engine is straight piped with about 5 feet of pipe, seems like 1 1/2" pipe... kinda narrow pipe I would think but maybe fine.
Truck runs fine, but does backfire on downgrades with a load on (it's a dump truck).
Should this engine have a muffler, or can the carb be tuned for it to run okay with a straight pipe?
Engine has a single barrel carb.
Dan | | | | | Joined: Mar 2007 Posts: 4,215 Moderator | | Moderator Joined: Mar 2007 Posts: 4,215 | Not street legal without a muffler where I live... | | | | | Joined: Aug 2001 Posts: 3,598 Moderator | | Moderator Joined: Aug 2001 Posts: 3,598 | Wish the LEO's would enforce the noise limit here in mid Mo.
On cars, trucks and Harley's.
I have to put my fingers in my ears sometimes when I'm outside.
They are that loud.
Don
1967 GMC 9500 Fire Ladder Truck"The Flag Pole"In the Stovebolt Gallery1946 2-Ton grain truck 1946 3/4-ton pickup, 1953 1-ton pickup 1957 1-ton flatbed dually, 1954 Pontiac Straight Eight Of all the things I've lost in my life, I miss my mind the most! | | | | | Joined: Mar 2009 Posts: 788 'Bolter | | 'Bolter Joined: Mar 2009 Posts: 788 | sounds like you don't want to spend any $ on it.
ron | | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | Yes you should have a muffler. The backfire may be something else. Summit has mufflers for $24. 1 1/2" inlet/outlet.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Mar 2018 Posts: 40 Wrench Fetcher | | Wrench Fetcher Joined: Mar 2018 Posts: 40 | I guess I mis-communicated...
Some engines run better with back pressure, and some will run fine with straight pipes.
I guess I should have put this in the engine section... my bad. :o
Dan | | | | | Joined: Feb 2004 Posts: 29,796 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,796 | Around my neighborhood running without a muffler can be hazardous to your health.
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Apr 2005 Posts: 7,440 Bolter | | Bolter Joined: Apr 2005 Posts: 7,440 | I ran without a muffler on my former '54 4100. Pipe straight out the back. Rather annoying after a while. I put a 24 inch glass pack on it and it became much more pleasant. Performance was the same if not slightly better with the muffler. 
Martin
'62 Chevy C-10 Stepside Shortbed (Restomod in progress)
'47 Chevy 3100 5 Window (long term project)
‘65 Chevy Biscayne (Emily)
‘39 Dodge Business Coupe (Clarence)
“I fought the law and the law won" now I are a retired one!
Support those brave men/women who stand the "Thin Blue Line"! Hug a cop!
USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)
| | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | Yes 1200 HP drag motors and formula 1 motors run better. But we were not taking about them. We all recommend a muffler on yours. It will not run better without a muffler, It will sound like it runs better to you, but not to the cops or your neighbors. You will get a headache on an extended trip.
Constant loud sound is how they get secrets from the enemy. So be careful not to give up your pin number.
To be clear, you can run without a muffler if you want to. There just is no known advantage to a 235 stock motor. IF the backfire is cause by low "backpressure", tuning the carb will not help. (not sure what "tuning" you would do to a B1). You may mess up a good running truck however. Adding a muffler may not stop the backfire either.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Mar 2018 Posts: 40 Wrench Fetcher | | Wrench Fetcher Joined: Mar 2018 Posts: 40 | Bartamos, thank you for that answer. I'll look into installing a muffler on the truck. It's got farm use tags on it so in Virginia, no inspection is needed, and the cops don't make an issue of it... but it is pretty darned loud to drive the thing. :o
thanks again, all
Dan | | |
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