Valve cover ground strap bolts...head markings

[Doug J.]

Could someone please tell me what the correct, most commonly seen, or possibly/commonly used, head markings are used on the 4 bolts that hold the ground straps to the valve covers on the braided wires. Car in question is a 1971 with a 454.

Thank you for any help,
Doug

[Kevin G.]

Re: Valve cover ground strap bolts...head markings

Mine are as shown......

[Bob D.]

Re: Valve cover ground strap bolts...head markings

Doug

The ones I have seen the most are the TR bolts, as pictured in Kevin's post, used for the spark plug ground straps. My '71 big block had the same bolt markings on the groud straps.

Bob

[Doug J.]

Re: Valve cover ground strap bolts...head markings

Kevin and Bob,

I have plenty of TR bolts for the straps. All the others are RBW, I'm hoping that they are correct? I recieved a deduct for having 4 SBC bolts with hardening marks last time, stating that A or C would be expected. Just trying not to make the same mistake twice.

Thanks for your responses,

Doug

[Mike E.]

Re: Valve cover ground strap bolts...head markings

Interesting. Why grade 8 bolts for an application like that? Curious

[Doug J.]

Re: Valve cover ground strap bolts...head markings

Mike,

I'm a little confused....where is there a grade 8 bolt?

[Ron G.]

Re: Valve cover ground strap bolts...head markings

Those TR bolts on Kevin's car are not grade 8, they are grade 5. Although RBW would not be ruled out as it is part of the GM family of hardware, I would go with the TR bolts as: a) they are the most commonly seen and B) I know Mr. Goodman's car original and is factory correct.

[Doug J.]

Re: Valve cover ground strap bolts...head markings

Ron,

That's what I was confused about, the picture is of a grade 5 bolt! I have RBW bolts on all the other places, and on the 4 places for the ground straps I used the TR bolts. I'm hoping that should be good.


Thanks......Doug

[Mike E.]

Re: Valve cover ground strap bolts...head markings

Right-grade 5. Grade 8 would have more striations. My bad.

[Dick W.]

Re: Valve cover ground strap bolts...head markings

Right-grade 5. Grade 8 would have more striations. My bad.

3 lines=5
5 lines=8

[Terry M.]

Re: Valve cover ground strap bolts...head markings

Not only do those big blocks need 7 bolts per rocker cover, they have to be grade 5 or 8 too! Heavy metal.

[John H.]

Re: Valve cover ground strap bolts...head markings

3 lines=5
5 lines=8

Dick -

6 lines = Grade 8

[Terry M.]

Re: Valve cover ground strap bolts...head markings

Dick -

6 lines = Grade 8

Dick is having a Terry day too.

[Kevin G.]

Re: Valve cover ground strap bolts...head markings

To keep it interesting, here's one from the other side.

[Doug J.]

Re: Valve cover ground strap bolts...head markings

Those TR bolts on Kevin's car are not grade 8, they are grade 5. Although RBW would not be ruled out as it is part of the GM family of hardware, I would go with the TR bolts as: a) they are the most commonly seen and B) I know Mr. Goodman's car original and is factory correct.

Ron, So it would be safe to say that using the grade 5 TR head marking bolts for the ground wires and the RBW head marking bolts for the others would be a safe bet? The RBW bolts have no grade markings..is that correct?


Thanks again.....Doug