041 X heads
 

An ad elsewhere here shows a pair of 041 X heads for sale. Excuse my ignorance, but what is an 041 X casting? Is it like the 461 X head, where would the X be found? Did it have a different combustion chamber like the 461 X, or is the X located someplace else on the heads? Also, are they legal anywhere a regular 461 head is accepted? Inquiring minds want to know.

Re: 041 X heads
 

Never heard of a 041 X head, and I live in Canada.

Re: 041 X heads
 

Re: 041 X heads
 

I saw those heads and was going to jump on them for my Stocker.
But, with the larger valves, they will not work for me.

Re: 041 X heads
 

That is because you did not spend years with your nose in Colvin's books before the Internet became the source for all info.

Re: 041 X heads
 

The X was found on a number of different castings including '441's

The '461 X was the most popular head in C/SM when that class was so popular. It did have larger intake runners and since porting wasn't allowed that's the head everyone tired to get.

I've seen other casting numbers with an X in various places but it usually didn't mean anything as far as runner size when we checked them many years ago

I've seen the X on the casting surface in various places and down inside the water jacket with the head facing you chamber side up....

Maybe there are people that know for sure why that was there and if they are any better but I am not one of those folks...

Re: 041 X heads
 

All the original 041X cylinder heads had 1.94" intake and 1.50" exhaust valves and used on the SBC 350/300HP engines.

If there are any 041 or 041X cylinder heads with 2.02" intake and 1.60" exhaust valves, they were modified and they also needed to unshroud the combustion chamber to clear the valves.

Re: 041 X heads
 

I have at set of 1.94 /1.50 unmolested 041X's that I would sell.
I can ship. Located Seattle WA.

Steve Teeter Stk/SS 620.
360 979 3126.

Re: 041 X heads
 

I was told long ago that sbc castings with a X were for police and taxi. Not sure about that info could never figure why a taxi would need a special head police maybe.
Terry

Re: 041 X heads
 

X was put on cores that were used up and out of spec in some manner.
When they ran short on cores they might make a run with cores that were marked X for out of spec. Most X castings were done in core boxes that were out of spec with worn runner molds. That made the runners larger than spec when they were poured. There are some castings that have X's in the lower core box, water jacket passages, and no X up on top with the casting number. Only half of the core was out of spec in those cases. That is the information I got from a person that was supposed to know, a long time ago.
Most X castings I have had come through my shop were anywhere from 3 to 10 CC larger on the runner. Most of the time it was in the bowl area on the short side or by the guide. There were some with funny shaped Ex.