70 L46 LT1 Aluminum Valve /Rocker Cover Bolts Headmarks

[Bill L.]

I have read that on some bolts on 71-72 LT1s can have an "R" head mark.

I also found that "M" head mark bolts seems to be the most common.

Could they be either M or R in 70 or just M for judging purposes?

Thanks,


Bill

[Mike E.]

Re: 70 L46 LT1 Aluminum Valve /Rocker Cover Bolts Headmarks

Bill,
I can't speak to the "R" bolts, but here is a picture of the bolts removed from the left valve cover of #6242, purchased from the original owner a couple of years ago. Note the two types of "M" bolts.
Regards,
Mikevalve cover bolts.jpg

[Rich P.]

Re: 70 L46 LT1 Aluminum Valve /Rocker Cover Bolts Headmarks

Bill I found R head marking bolts to come out around 71 possibly late 70 but mostly 71 and up

[Bill L.]

Re: 70 L46 LT1 Aluminum Valve /Rocker Cover Bolts Headmarks

Bill,
I can't speak to the "R" bolts, but here is a picture of the bolts removed from the left valve cover of #6242, purchased from the original owner a couple of years ago. Note the two types of "M" bolts.
Regards,
Mike[ATTACH=CONFIG]65822[/ATTACH]

Thank you Mike.

Kind Regards,


Bill

[Bill L.]

Re: 70 L46 LT1 Aluminum Valve /Rocker Cover Bolts Headmarks

Bill I found R head marking bolts to come out around 71 possibly late 70 but mostly 71 and up

Hi Rich,

Kinda what I surmized based on research too. Just wanted to confirm. The repros are not hateful but are clearly discernible.

Kind Regards,


Bill