1955 exhaust resonators or no resonators

[Bob Kielar]

Art Gardner posted the service bulletin on the 55 exhaust. It states the elimination of resonators in 1955. I looked at my Authenticity manual and it states that after engine number 82750 the resonators were eliminated. The engine number on my block is 5560128828 so do I need resonators?

Regards,
Bob Kielar

[Caddy Wizard]

I would think no, you don't need them.  By the time your car rolled off the line, they weren't installing them any more...

[Bob Kielar]

Would points be deducted at a grand national if I had them?

Regards,
Bob Kielar

[Dan LeBlanc]

If the judges get to that level of nit-picking where they compare running changes to a VIN, I'll start parking my Cadillac on the street or show up in my Continental and walk in to the show as a spectator.

Really, likely nobody would notice.

[Mike Josephic CLC #3877]

In theory "YES" points would be deducted.  However, it's really doubtful
that most judges would check the engine number and then check for
resonators.  So, you're taking a chance but I think luck is on your side.

BTW, I judged at about 25 of them.  We seldom checked engine numbers
vs. all of the running changes that were made.  If you have a set of the
monthly technical bulletins that detailed all of the model year changes,
there were MANY.  You would have to carry an encyclopedia with you to judge.

Mike

[Ralph Messina CLC 4937]

Bob,

The Authenticity Manual may be incorrect. The '57 MPL shows a resonator was used before engine 82499 and after engine 104903. They were also used  from '56 through at least 1960. If this correct, your engine number should have resonators. I have no idea why they would be eliminated for those middle 22 thousand cars, but it could be be as simple as supply problems. Resonators effect the sound quality, not necessarily the volume, of the exhaust note.

HTH,

[J. Gomez]

  well something did changed 

[Mike Josephic CLC #3877]

According to my copy of the "Cadillac Serviceman", the monthly technical
bulletins, resonators were eliminated after Engine Number 82750.  This was
roughly in April - May, 1955.

My Eldorado, having the engine number 21363, being an early car shipping
in December 1954 correctly HAS resonators.  With an early number like your
car, 28828, your car correctly should have resonators as well.

Sorry about any confusion, I should have checked your serial number against
mine and the Tech Bulletins before.

The good news is, you don't have any issue!

Mike

[Jay Friedman]

I believe the engine number on his car is 128828. 

[Mike Josephic CLC #3877]

Jay -- if it is 128828 then, of course, it's a whole different story.
My mistake not taking the "1" into account.

I'm not sure where that number falls in the production number
sequence but it's obviously much later in the year.  Maybe Bob
knows -- perhaps he has the "cars built" sheet?

Mike

[Bob Kielar]

I have the build sheet the car was built in August. The way I'm understanding this is that a 55 Cadillac with a engine number before #82499 and after #104903 had resonators. The 22,404 in between these numbers had no resonators. So mine being #128828 the car originally had resonators is that correct?
If so what a relief. I ordered my new exhaust nine weeks ago with resonators. I contacted them today and they have already fabricated the new pipes but the mufflers are back ordered until the 22 of November. Oh well it's a winter project. Thank you everyone for your input.

Regards,
Bob Kielar

[Caddy Wizard]

I think we can all see what happened now.  During the 55 model year, at a certain point Cadillac stopped including the resonators on the S62 and S60 models.  That happened around engine 82xxx.  But after they did that, they started getting customer complaints about some sort of exhaust "booming" (whatever that was).  Apparently, the Fleetwood owners, having the most expensive Cadillac and being the most fussy, complained the most.  So Cadillac added the resonators back to the FW cars beginning around engine 104xxx.  Interestingly, they didn't add them back for the S62 cars (I am guessing that this was a cost-cutting maneuver).  The Serviceman letter article I posted elsewhere on this Forum makes all of this clear, if you read it with the above explanation in your mind.  Here is a link to that (I would post it here directly, but like many others, I am having trouble posting images). 

http://forums.cadillaclasalleclub.org/index.php?topic=147331.0

So Bob, your late 55 FW should have the resonators to be factory-authentic for your particular car, IMO.

[Mike Josephic CLC #3877]

Thanks Art for clearing that up.  I found the article on page 43 of the
"Service Man" book for 1955.  It confirms that the factory started to
install resonators on all 60S cars effective with engine number 104,000,
but not on the series 62's.

By the way, I didn't know that Bob's car was a Fleetwood (60S).

I also learned something new, as Paul Harvey used to say "The rest of the
story........."

Mike

[Caddy Wizard]

Mike,

You should see Bob's car in person some time.  You can't imagine how flattering the Deep Cherry paint is on a Fleetwood until you see it on his car.  Just wonderful.  If you look at the little paint chips from Dupont or R-M, which are over 50 years old now, you can't see how pretty the color is.

Art

[bullet bob]

Bob. Not trying to hijack a thread here, but am curious where you ordered your exhaust system from. Thanks
Bob

[Bob Kielar]

Art,
      Thanks for the kind words,your opinions are always appreciated.

Regards,
Bob Kielar

[Bob Kielar]

Bob,
       I ordered my exhaust from Waldron. If you are thinking of ordering a exhaust system check out the thread on Mid-Century Cadillac forum started by South Paw.

Regards,
Bob Kielar