C3 - '71 350/270hp cam question

[Jim Callan]

Would this engine have a 'cam button' ? I disassembled this engine and 'bagged and tagged' everything, and I don't have anything that looks like a 'button'. The rebuild manual says to "make sure the cam/thrust button is installed" before the timing cover is installed. What have I missed or lost ?

Thanks

[William C.]

Re: C3 - '71 350/270hp cam question

Stock cam does not use the "thrust button" Many aftermarket Roller cams need it. The GM service manual does not mention it, you must be looking at a "hot Rod" rebuild guide.

[Jim Callan]

Re: C3 - '71 350/270hp cam question

Thanks Bill - I'm using a haynes rebuild manual.

[John H.]

Re: C3 - '71 350/270hp cam question

Good reason to use the GM manuals instead; the Haynes/Chilton manuals are way too generic.

[Joe L.]

Re: C3 - '71 350/270hp cam question

Jim------

The strange thing is that cam buttons were never used on ANY PRODUCTION or SERVICE GM small block or big block engine assembly. They are strictly an aftermarket-type item, although GMPP does sell them for certain "high performance" use.

All GM PRODUCTION or SERVICE engine assemblies that use a roller camshaft requiring thrust control use a thrust plate that attaches to the block with 2 special screws. This system is FAR better than the thrust button approach, but it cannot be retrofitted to blocks not originally so-equipped. So, the cam button is used when aftermarket roller cams are used in blocks not originally using a roller cam.

[Craig S.]

Re: C3 - '71 350/270hp cam question

Haynes and Chilton are good door stops.......get the GM manual.....Craig