Intake Valve -- What is this contraption??

[Thomas H.]

I'm not a professional engine builder, but I have done my fair share over the years and I have never seen anything like this. I removed these today from a SBC head I recently picked up. The only thing I can think is that it is there to "help" slow down the valve closing as it reaches fully closed. Must do wonders for airflow.........

Tom

[Paul D.]

Re: Intake Valve -- What is this contraption??

I've never seen anything like that, but I'm no expert. It appears to be intended to help with oil control. The "cup" looks like it contains some sort of packing. Maybe some rebuilder's idea of a better mousetrap. That spring looks like a recipe for disaster eventually.
Chip

[John F.]

Re: Intake Valve -- What is this contraption??

Must be from the kids that flunked shop class.

[Joe L.]

Re: Intake Valve -- What is this contraption??

Tom------


This is some sort of aftermarket valve assembly. It's not just a case of the springs being added to stock valves as the valve stem is designed to somehow accommodate the spring assembly. Note that the valves are embossed "USA" which is not found on GM valves.

I have no idea what this configuration is supposed to accomplish.

[Thomas H.]

Re: Intake Valve -- What is this contraption??

Well, I'm kind of glad they were there. I used them to haggle the price down another $50................

The washer appears to be made of some fiber / packing material very similar to those you find in plumbing fixtures. When I get some more garage time, I'm going to take one off to see if there is a groove in the valve stem.

Funny thing was, guy had them on an engine that had been sitting and never run. He decided to go with a different build so off came the heads. They were not a matched pair, each a different casting. This one is a 770 with the X58 and a casting date that aligns with my 58, so I picked it up. I don't know if the other head had these intake valve "enhancements" or not as I was dealing through a third party. Either way, the casting is in good shape so that is all I'm interested in.

Tom

[John H.]

Re: Intake Valve -- What is this contraption??

That's the damnedest thing I've ever seen; I've had engines apart for 50 years, and I've never seen anything like that - don't remember seeing anything like it in the old J.C. Whitney or Warshawsky catalogs either. Can't imagine what it's all about.

[Stuart F.]

Re: Intake Valve -- What is this contraption??

An early attempt at a Desdromic Valve???

Stu Fox

[Richard M.]

Re: Intake Valve -- What is this contraption??

Yikes!

Hmmm, like brake drum springs, I think they're there to keep (HSLVT)* noise to a minimum.

Either that or the spring is to be tack welded to the valve body so when the 2-piece valve stem weld breaks, it keeps it from falling into the cylinder.

* (HSLVT) = Harmonic Solid Lifter Valve Train

[John H.]

Re: Intake Valve -- What is this contraption??

An early attempt at a Desdromic Valve???

Stu Fox

Stu -

That contraption is too small in diameter to make contact with the valve seat or interfere with full closing of the valve - it just interferes with airflow and creates turbulence. Will be interesting to see how it's attached to the valve.

[Domenic T.]

Re: Intake Valve -- What is this contraption??

My best guess is that it was supposed to be used to lap valves. I use a similar spring when I do valve seats, my own concoction but when I spin a stone on the seat I can let the spring raise the stone and come off full speed.
SOOOO maybe this is used to rais the valve when hand lapping if your valve won't accept the suction cup.
My next guess is that someone gave them to an enemy or someone they wanted to race!!! Can't imagine what damage those springs could do?

Dom

[Stuart F.]

Re: Intake Valve -- What is this contraption??

Still a first for me. The only other use for a valve in an engine that remember was one I modified to make a tool to fly cut notches into flat pistons. This was done on early 265's mostly when putting in a Duntov cam which upped the redline by at least 1000 rpm in an engine not designed for it. As I recall, these stock engines did not have the Moraine 400 bearings either so it was just a matter of time before something had to give. My first 55 V8 that I had in my 50 Chevy coupe floated the valves just by adding tri power carburation. It did not run too well after that so I traded it in at a Milwaukee junk yard for a 56 Corvette engine w/o the dual Quads. But, I became an advocate for fly cutting pistons, not only on Chevy 265's, but I made a set for Ford 312's.

Stu Fox

[Harold W.]

Re: Intake Valve -- What is this contraption??

I recall something similar on my '54 when I tore it down in 1973 for an engine rebuild, as it was burning oil when I bought it in 1972. It appeared, on mine, to be an auxiliary oil seal for the valves. The spring held the seal against the guide surface. Of course, I took them out and redid the valve guides. Seemed like a waste as you had to take everything apart anyway. Thanks for the memories. BTW, it's still running without an oil cloud.

[Thomas H.]

Re: Intake Valve -- What is this contraption??

Stu -

That contraption is too small in diameter to make contact with the valve seat or interfere with full closing of the valve - it just interferes with airflow and creates turbulence. Will be interesting to see how it's attached to the valve.

John,

Took one apart. Attachment seemed to be a press fit. No grooves or anything that would serve to lock the top in place. I took some pictures, but seem to have either misplaced them or deleted them.

Tom

[Thomas H.]

Re: Intake Valve -- What is this contraption??

I recall something similar on my '54 when I tore it down in 1973 for an engine rebuild, as it was burning oil when I bought it in 1972. It appeared, on mine, to be an auxiliary oil seal for the valves. The spring held the seal against the guide surface. Of course, I took them out and redid the valve guides. Seemed like a waste as you had to take everything apart anyway. Thanks for the memories. BTW, it's still running without an oil cloud.

Interesting. Thanks for the response.

[Joe C.]

Re: Intake Valve -- What is this contraption??

The first thing that occurs to me is that the spring loaded packing will contact the underside of the valve stem boss to help control oil flow.

But, when I went to my college textbooks and especially my notebooks, I discovered an obscure technology that was in a prenatal stage in the early seventies. It was designed to be the answer to the 1973 oil embargo, and akin to the Fish carburetor and other flibbertigibit devices being experimented with in northern Europe at the time. The theory involved a negative Coriolis effect on the intake charge which would impart a Canasta aurora to the hall effect and essentially dilate the homogenization of the vapor point which would, in fact, make the charge an adiabatic-isentropic as well as isothermal emulsion, thus increasing thermal efficiency as well as MEP. The antidisestablishmentarianism effect was thought to be on the order of .000001 picrons, and the Avogadro number for the molar equivalent is outstanding.