Marking on 1962 461X head

[Mike E.]

I've seen this on too many heads from too many different parts in the country over 40 years for this to be from a machine shop. I am convinced that it is a factory stamp. Does anyone have an idea why this mark is stamped on some 461 heads?
Thanks,
Mike
P1300316.jpg

[Richard M.]

Re: Marking on 1962 461X head

Mike, I just checked the 461's that are on my '59, a '61 519 block with later heads. Actually they're 1965 461's and it has the exact same "C" stamp mark. Also have 4 1962 and 1963 461 heads, those have a "6", a "L", and a "E". Can't see the 4th it's buried. I'll try later.

These are not "X"'s, just regular old 461's.

Maybe a inspector stamp when machined or assembled at the Flint Plant?

Rich

[John D.]

Re: Marking on 1962 461X head

Inspection mark ? When we visited Flint in '92 at the convention the inspectors had hammers that were made with symbols on the face. Once the engine passed the hot test the inspector would hit the hammer on the engine..dont remember exactly where.

[Tom P.]

Re: Marking on 1962 461X head

Rich,
As I understand it, ALL 61-63 461 heads are X heads. The X is found on the underside of the head.

[Richard M.]

Re: Marking on 1962 461X head

Rich,
As I understand it, ALL 61-63 461 heads are X heads. The X is found on the underside of the head.

Thanks Tom, I'll have to dig those 2 off the shelves and check dates and for the "X". I have another 2 on a '61 519 block bolted down temporarily so I won't be able to check those for a while.

Rich

[Timothy B.]

Re: Marking on 1962 461X head

Rich,

You can check them from the top by looking at the lower valve cover threaded hole area. The 461X does not have the lump (extra material) around the threaded hole, it's just straight across.

[Richard M.]

Re: Marking on 1962 461X head

Rich,

You can check them from the top by looking at the lower valve cover threaded hole area. The 461X does not have the lump (extra material) around the threaded hole, it's just straight across.

Ahh, good info Thanks! So then I'll be able to see that feature on the mounted heads also as the valve covers are off.

On a sidenote, the "X" designation was only on certain "test runs" in the casting facilty in Saginaw, is that correct?

Rich

[Duke W.]

Re: Marking on 1962 461X head

My understanding is the same at Tom's in post #4. All '61-'63 "big port" heads are 461X.

The '61 applications were only the 275/315 HP Corvette FI engines, so this is how they got the name "fuel injection heads". They became the hot setup because they flowed much better on the inlet side than the earlier "small port" heads, also known as "283 heads".

In '62-'63 utilization was expanded to include all 300 HP engines used in the full size car and Corvette and the 340/360 HP Corvette engines, so the term fuel injection heads became a misnomer.

All 461 X heads were machined for the 1.94/1.50" valve size, and Bill Clupper recommends NOT enlarging them. Later versions of the big port heads - 461, 462, 186, etc. - could be machined for both the standard valve size (1.94/1.50") for the 300 HP engine or 2.02/1.60" for SHP/FI engines.

Duke

[Patrick S.]

Re: Marking on 1962 461X head

Mike,
Both of the heads of my 62 Fuelie have a stamped mark. I would show you but the site will not take the pictures.
Pat

[Tom L.]

Re: Marking on 1962 461X head

We ran 461X heads on out street stock race car with enlarged valves, 2.02 and 1.60's for several seasons at 7,000 rpm plus with no issues. MIGHT have even ported them. Could it be the machinst????

[Eric E.]

Re: Marking on 1962 461X head

Mike,
Here is a mark on one of my 461 heads dated Sept 11, 61 (I111).

[David D.]

Re: Casting on my 461 X Head

461 x heads dated Feb 61 shows one hump
Ground down. Wish I could send a photo but don't see an option on this non friendly user interface.
Perhaps I'm just to old to participate in the new order.

[Tom P.]

Re: Casting on my 461 X Head

461 x heads dated Feb 61 shows one hump
Ground down. Wish I could send a photo but don't see an option on this non friendly user interface.
Perhaps I'm just to old to participate in the new order.

You mean like this?

[James G.]

Re: Marking on 1962 461X head

We ran 461X heads on out street stock race car with enlarged valves, 2.02 and 1.60's for several seasons at 7,000 rpm plus with no issues. MIGHT have even ported them. Could it be the machinst????

I DID ALSO FOR 5 YEARS 1989-94. TOM COTTER has the car today. Motor has been rebuilt, still no problems, same heads with nice new valve job.

[David D.]

Re: Marking on 1962 461X head

My heads show about 1/2 of the 'hump area' is ground down, same on only one end of each head. How in the world can I submit a photo.