Packard Forum Index » V-8 (1955-56)

I'd like very much to know what the correct tail pipe diameter is for a 1950 (23rd series) Eight (2301, 288 ci engine). I'm pursuing a chronic overheating problem with this car and have been through EVERYTHING I can think of and am running out of ideas. Current tail pipe measures 1-3/4 diameter OD which is smaller than the 288 engine had a few years later.

According to specs in service counselor Vol23 #5, the 288 & 327 eng should be 2 1/4 and the 356 should be 2 1/2. Muffler is 5 9/16 x 37 3/8 with 356 larger. 6 cylinder cars used a 2 inch. Only specific mention in parts manual for a 1 3/4 is for model 2232. Don't have a convenient reference at hand as to which car that is.

Thanks for that. My 47 Super Clipper with the 356 engine has a 1 3/4" tailpipe which I suspected was incorrect for siuch a large engine yet the muffler does look old and possibly even original. I have no overheating issues but I don't think that a 1 3/4" pipe is large enough so I will have to go shopping for a new muffler.

HH56: Thanks for checking on this for me, could you please just clarify that the 2-1/4 is the tail pipe diameter for a 288 engine, and not the exhaust pipe diameter?

You're correct, that is exhaust pipe from eng to muffler. What gets more curioser is that the specs from 21st series data book are same as 22-23rd mentioned from SC but my 47 2106 (conveniently disassembled) instead of the 2 1/2 spec'd has a 2 1/4 pipe and the 1 3/4 in tailpipe as 47 clipper noted for his.

Maybe they decided large wasn't necessary or because of shortages, used what was available. Since my car wasn't when running nor 47 clippers is now having overheating issues, maybe tailpipe is not the answer on your smaller engine either.

Does the vacuum number indicate any kind of restriction? A friend had overheat issues on his 51 that turned out to be the manifold valve opening but sticking just partially open somehow. Said it took forever to find but he was also burning valves and on the 3rd grind, the mechanic took manifold apart and found true problem.

The engine pulls a rock-steady 19 inches of manifold vacuum when idling, and other than overheating at idle even on cool days runs extremely well. I'm beginning to discount the tail pipe restriction for another reason - logic would seem to say that at idle with so little exhaust product to move, it couldn't be the problem; a restricted exhaust might be expected to manifest itself more at higher speeds though I do recognize that the heat exchange from the better air speed over the radiator would counteract that. As to the heat riser, its broken but I'm told it's wide open (counterweight down). This one really has me baffled, block exceptionally clean inside, water distribution tube perfect, timing OK, new 4-row radiator and water pump. I hate to use an external electric fan, that's generally not a good idea, it just masks the problem, kind of like taking a pain killer after you sprain you back so you can back out and split some firewood. Open to any ideas, no matter how far-fetched.

Does it overheat if you take the thermostat out?

The reason I am asking is that know people that have had problem with there Packard's overheating when they used a modern style thermostat. I guess the old bellows style ones flowed better (according to them). Once they swapped in the bellows style one, there overheating problems when away.

I figure the quickest way to test this would be to pull the thermostat out temporaraly, and see what happens.

Just a wild idea, and I am passing this along as 3rd party here-say.

Attach file:

---

  (20.38 KB)