What is this?

[Wayne K.]

Re: What is this?

If you do ever find it was a GM accessory and will fit a 55 I have to have one

Roy,

For you we'll make em fit.

[Wayne K.]

Re: What is this?

This may confuse more than help but I remember seeing something vaguely similar back in the late 60s/early 70's.

This was on a medium size cabin cruiser powered by twin inboard SBCs. Each of the engines had one manifold equipped with a similar trumpet-looking device, however it was lying flat almost parallel with the manifold. I asked the owner about the function and remember getting a mumbled answer about 'ventilating the engine compartment (of gas fumes)'.

As the engine were operating at the time and in a smallish space I didn't get a chance to explore further.

I think your spot on. The exhaust flow would cause sucking not blowing through the horn. The cover is to keep large objects from entering. I'll bet the guys wife is related to mine in that she was always complaining about the smell of gas fumes when she rode in the car.

[Joe C.]

Re: What is this?

I posted for the first time a week ago, but was unable to get my pictures uploaded. Long story short, I own a '56 that I am restoring. I have had it in storage for many years now, but now that I am retired I'll have the time to do it right. At any rate, the exhaust manifolds for my car have what I can only describe as a "bugle" attached to them. I was told by the PO that they were original to the car, and that he didn't know what purpose they served. They appear to serve some sort of pressure relief purpose, to either let air into the exhaust manifild, or let gases out of the manifold. It is too well manufactured for it to be some home made modification, and I don't believe that it is an aftermarket add-on.

Has anyone seen these before? If so, what are they for? Is it possible they're an experiment by Chevrolet or something like that? Would they enhance the value of my Vette? Any advice would be appreciated.

Thanks,

Ski

Louis Armstrong on speed!

[Joe C.]

Re: What is this?

Ski,
Regarding the continuing saga of the "bugles". Did you ever drive the car with the "bugles" attached? If not, will they clear the hood when it is closed? Are the manifolds in fact original GM manifolds with casting numbers and other tell tales? This reminds me of the "Montauk Monster" that was kicked around the 'net recently. Keep on buglin'.
Best regards,

Keep on Chooglin'
Creedence Clearwater Revival
1969

[Bernard M.]

Re: What is this?

Leon,
The manifold casting number is correct for all but the very earliest '56 Corvettes. The 557 and 558 castings are a one-year-only item and are themselves quite rare, although they have been reproduced. The bugles, however, are new to me. Can you determine whether the manifolds have been tapped or if these are pressed in? Be very careful when you remove them (and I'm pretty sure you're going to want to do that). Originals of these early design exhaust manifolds had very thin walls and were prone to cracking. The reproductions were superior in this regard.
Bernie

[Louis T.]

Re: What is this?

I think these might be some sort of manifold resonance tuning device, possibly intended for racing and modeled after similar devices on vintage aircraft engines.

[Leon M.]

Re: What is this?

Wow! I am very impressed by the responses thus far. I think we can safely rule out a mosquito spraying device, or an audible warnig mechanism. The "bugles" will allow pressure to be drawn into the manifold, but will not release pressure out, there is clearly a check valve inside. I am trying to post some additional pics (fingers crossed) (never mid the file is too big I'll nabe to save it in a smaller format), but the manifolds appear to be origianlly tapped (not heli coiled) to accept these devices. It is too clean to be an after market job (sorry for the bad pics, my Son-In-Law took them after several Rum and Cokes)

At any rate, I appreciate everyone's input. If / when I ever solve this mystery I will buy my son-in-law his own '56 to restore (not).

Thanks,

Ski

[Noel K.]

Re: What is this?

I wish I could state that I know what these were specifically used for. I do remember my dad, who ran his own garage and service station into the early '70s,put two of these on the exhaust manifolds of a 1956 Ford Fairlane with the 312 c.i. engine that he owned. I remember one of the neatest things he gave me was a steering knob that attached to the steering wheel and was spring loaded and would rotate to be parallel with the steering wheel instead of perpindicular. The precursor of power steering !

He was always trying out some "gadget" that the parts salesman would bring around from the local NAPA store.

I do know they didn't make any sort of noise - so rule out any parade function ! And we never had any mosquitoes when I was growing up in central Indiana - perhaps this is why ?

Hope someone comes up with a definitive answer.

[Stuart F.]

Re: What is this?

I think you're starting to hit on something in that they are probably an aftermarket doo dad from the likes of J. C. Whitney typical of the "pin Wheel" or "air bleed" gas savings devices. In this case, if as you say they are able to draw air in to the manifolds, it must be for some type of afterburning function.

Stu Fox

[Martin N.]

Re: What is this?

I'm incline to follow Stu's thinking, probably some sort of after market fuel saving device. What was the cost of gas back then? Maybe I should try those on my 07 CTS.

Marty

[Joe C.]

Re: What is this?

I posted for the first time a week ago, but was unable to get my pictures uploaded. Long story short, I own a '56 that I am restoring. I have had it in storage for many years now, but now that I am retired I'll have the time to do it right. At any rate, the exhaust manifolds for my car have what I can only describe as a "bugle" attached to them. I was told by the PO that they were original to the car, and that he didn't know what purpose they served. They appear to serve some sort of pressure relief purpose, to either let air into the exhaust manifild, or let gases out of the manifold. It is too well manufactured for it to be some home made modification, and I don't believe that it is an aftermarket add-on.

Has anyone seen these before? If so, what are they for? Is it possible they're an experiment by Chevrolet or something like that? Would they enhance the value of my Vette? Any advice would be appreciated.

Thanks,

Ski

Stu,

Is there a Pitot Tube present in the flow path, and if so, how far downstream is its terminus?

Joe

[Stuart F.]

Re: What is this?

Joe;

Interesting thought. Guess we'll have to ask Leon about that. Are you thinking this may have been from a home built aircraft? Or, how about an air boat? We have a lot of those, incl. Chevy powered, down here now searching for little Caylee Anthony in the swampy areas.

Stu fox