VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1912-1928 1927 Coach exhaust system

I have invested in a complete exhaust system for my 1927 Coach (Matilda) from The Filling Station. They do not list any attachment devices for their 1927 system.

Matilda's exhaust system was obviously not stock when I bought her. The pipe into the muffler from the "stove" had a hanger welded to the pipe and car frame which left the muffler 2" below the factory muffler bracket. The tail pipe was hanging from a rubber suspension device which allows the tail pipe to swing. There were no clamps on any of the pipe slip connections.

How should the stock pipes and muffler be secured to the car frame? I would suspect that since the engine is solidly bolted to the frame (no rubber motor mounts) the pipes should be connected solidly to the car frame. If so, where are their attachment points? Also, should there be any pipe clamps or is the system all "slip fit'??

Thanks in advance,
Bob D.
1927 Coach "Matilda"
Susanville, CA

Originally only the manifold outlet and factory muffler bracket held the exhaust system. There was packing between the manifold outlet and inside of pipe. A strap with a special "bolt" with oval headed slot (where the strap was folded over itself) that tightened into the hole in the bracket end. The tail pipe was only a foot or so out the back of the muffler. If you (and most of us that drive our cars) have a full length tail pipe that exits behind the body it will be necessary to add a hanger secured to the lip of the rear cross member. It is not original but safer for the occupants.

Just to make Chippers entry a bit clearer, a clamp is NOT used where the pipe slips over the exhaust manifold. A clamp as described holds the muffler to the muffler bracket. Also as recommended we all suggest you extend the tail pipe completely out the back of the body. That makes the rear clamp and bracket necessary.

Have fun,

G'day Chipper. I used to make reproduction exhaust systems a long while ago, made about 600 from 490 to 28.
I used nos samples as templates. I was under the impession that the 27 tail pipe was about 3' long and the 28 about 4'
Of course tailpipes were an optional extra and the were baffled in 2 places and the outlet.
I've still got a nos 28 tailpipe in my Chev memorabilia collection.
Chris

Chris, I know what you are talking about with the crimps on the tailpipe, but an explanation or picture would help the others.

Thanks for the info. You all are wonderful sources of info. If anyone thinks of something else, please speak up. I will be starting the exhaust project on 3/15/2012 if the current storm does not drop too much snow.

I am wondering about what "crimps on the tailpipe" refers to.
Bob D.
1927 Coach "Matilda"
Susanville, CA

I also believe that the early 28's were delivered with a short tail pipe similar to those used during the 27 model year. I have a Minograph copy of a document titled "Engineering Data for 1928". Within this document there is a picture of a assembled exhaust/stove pipe, muffler, and tailpipe with the hanger in place. The tailpipe would appear to be somewhere in the 32 to 36 inch length (about twice the length of the muffler). The tailpipe is flutted (flattened - distorted) approximately 8 - 9 inches rearward of the muffler and a second flutted area approximately 7 - 8 inches rearward of the first flute at 90º from the first flute.

The September 1928 Service News has the following information. "New Released Muffler, Exhaust Pipe, and Tail Pipe". "A new and improved Muffler, Exhause Pipe and {longer} Tail Pipe is now in production and is also available for service in the National Series Passenger Cars 1/2 Ton Trucks. [The notice goes on to list the the part numbers and names of the items released].

Chevrolet must have realized later that they had forgotten something because in the November Service News they released the usage of additional tail pipe hangers for the September Muffler system. A tail pipe hanger was added at the top of the kick-up area (over the axle) which supported the pipe laterally off the frame side member and a second hanger between the tail pipe and the gas tank right side strap. (The rear hanger gripped the edges of the gas tank strap and supported the pipe in the vertical direction).

Chris O has sent the above pictures of a 1928 top and a 1929 bottom tail pipes showing the crimps.


4-cylinder systems. Top is 1928 and the bottom is 1929 showing the crimps.

Wow!
What was the purpose of the "crimps"? They are huge!!!
Bob D.
1927 Coach "Matilda"
Susanville, CA

Ray
Thanks for posting my pictures
The long one is 28 and the short one is 25-27
Chris

As Bev Bob says about the crimps, WOW.

Would that amount of exhaust restriction affect the engine performance and is that where the tradional "meat and potatoes " exhaust note on Chev 4's comes from.

Dont get that on my 2 inch full length system.

Cheers

Ray

Just to explain the whole system for those who don't know.
The engine pipe (complete with hot box) finished approx 9" past the muffler bracket and had the hole in the end of the pipe sealed. 2 1/2" before the end were 4 large holes for the exhaust to outlet into a larger cylinder. This the had 4 large holes near the front for the exhaust to outlet into the outer muffler case and exit via an oval elongated curved slot to the shape of the end plate, as seen on the inlet end of the tailpipe.
The crimps in the tailpipe were a 'sort of' baffle as well.
You can tell whether a Chev 4 has an original style exhaust just by listening to one drive past.
The cars with full lenght non original systems just don't sound the same
Chris

Personal choice is a great thing. Its originality versus practicality. A noisy, possibly dangereous and in some states an illegal stubby exhaust, versus a full length system, leaving the sound behind and not under you, and being able to hold a normal voice level conversation with front and back seat passengers.

Cheers

Ray

I can't imagine that the original style tail pipe would not restrict the exhaust some. That would reduce gas flow and limit horsepower. Sacrificing originality for drive-ability and safety is a no brainer in my mind.

Gidday fellas,

Yep I'm with Ray on this one, as I also recently fitted a 2" exhaust pipe with long tail pipe out the back end and from inside his car when travelling along is very quiet, easy to talk to one another and no stinky fumes which are thrown clear out the back, just to easy and safe.

http://montythe1928chevrolet.blogspot.com.au/2011/10/resto-stainless-steel-exhaust-fitted.html

Sorry but sometimes 83yr old designs do become a little outdated and lack some smarts, but each to their own I guess.

Thru my little dab of racing experience, I learned that restriction creates torque, power very good but, these engines didnt have much anyway so(and I cant speak for the master minds of creation) maybe that was done to create torque. For better take offs or pulling. ???? Just a thought.

Good day to you all,

Power, Torque, Take offs, Pulling away. Hang on, arent we talking about a Chev 4. Having spent the last few months looking around for a 28 up here in Sydney and around the state, I have spent a bit of time in a few cars going for test drives. Some were very nice, some where rough diamonds. Some were original, maybe, some were fully restored. There was one difference. I could only hear the driver talking to me in the cars that had a full length exhaust. On the 2 or 3 with "original" spec stubby exhaust forget it, just nod your head.

I know what I will be buying if and when I do, as I would not want the car to be so original that its too darn hard to drive, or dangerous, that's not fun to me. I think the most original cars are probably on blocks in the museum or pushed on and off trailers at car shows.

That's about all I have to say on the matter.

Totally agree with extended exhaust. We were discussing the application of the crimps and flatened exhaust tips. ?? Explore the possibilities.

Afternoon All, (well it is in Melbourne)

I have no experience with crimping or restricting exhausts so I can't comment on the subject.

When I put my Chev on the road back in 75, I had a reproduction short exhaust system that I think came from either Peter Jackson or Tony Noonan in NSW. Anyway the thing was so noisy, and the headaches. I had to replace it after about a week.

The most recent experience long versus short systems was last year when I was talking to another Chev guy at a club event

http://my28chev.blogspot.com.au/2011/10/2011-last-of-chrome-bumpers-lardners.html

Now his car is very nice, very smart, and very original looking in all respects. He asked me if I had a full length system and replied that he had an original short system and could not talk to people when driving.

Regards

Ray