65 396 intake manifold bolts

[Mike H.]

Does anyone the correct intake bolts for the 396. The judging manual says they are FP or with an A and both are black phosphate. Long Island Corvette Supply says the the headmark should be M and they are zinc. Paragon says the headmark is FP but theirs is zinc as well. Thanks

[Rich P.]

Re: 65 396 intake manifold bolts

Mike,

FP Zinc is what I have seen on original untouched cars.

Rich

[Jim N.]

Re: 65 396 intake manifold bolts

Does anyone the correct intake bolts for the 396. The judging manual says they are FP or with an A and both are black phosphate. Long Island Corvette Supply says the the headmark should be M and they are zinc. Paragon says the headmark is FP but theirs is zinc as well. Thanks

Mike,
my 65 396 intake bolts are black phosphate with FP headmark .
Jim

[Alan D.]

Re: 65 396 intake manifold bolts

Also consider that the bolts may be black however if silver paint was done to valley/head area similar to the SB process then that would be a reason why people are saying silver (zinc). Consider that some C3 use the black but they get painted silver except say one holding the coil which remains black.

If you have a part number (from AIM) post and see if anyone has it listed in a GM manual since that may also list the finish. Just a thought.

[Wayne M.]

Re: 65 396 intake manifold bolts

IMO, there's an inconsistency in the description of the manifold area in the 5th ed. of the '65 TIM&JG.

Manifold: "L78 intakes are unpainted aluminum with possible orange overspray along the edges"

Bolts, L78: "Known original cars use black phosphate recessed hex-head with 'FP' and integral washer, or flat hex-head with an 'A' headmark with three radial lines and integral washer. The bolts are painted silver during the intake painting process".

So which is it .

[Rich P.]

Re: 65 396 intake manifold bolts

IMO, there's an inconsistency in the description of the manifold area in the 5th ed. of the '65 TIM&JG.

Manifold: "L78 intakes are unpainted aluminum with possible orange overspray along the edges"

Bolts, L78: "Known original cars use black phosphate recessed hex-head with 'FP' and integral washer, or flat hex-head with an 'A' headmark with three radial lines and integral washer. The bolts are painted silver during the intake painting process".

So which is it .

I was going to post this same thing the other night but got distracted.

I think somewhere the aluminum small block intake manifold painting process got slipped in here. The reason they shot silver on the aluminum intakes was to cover the bare steel on the head between the unpainted valve cover and aluminum intake.
The 65 396 had a painted valve cover and had a aluminum intake. So as you know there is orange overspray the entire perimiter of the intake and no silver paint over spray.
I still say the FP and A intake bolts were cad not black.

Rich

[Jody B.]

Re: 65 396 intake manifold bolts

Here are pictures of my 396 FP intake bolts that I believe are untouched & original.

[Rich P.]

Re: 65 396 intake manifold bolts

Jody,

Nice pics of REAL FP bolts that look cad plaed with orange over spray. The repro FP bolts have a much different font and can be spotted a mile away.

Rich

[Jody B.]

Re: 65 396 intake manifold bolts

Thanks Rich, I agree with you and Wayne regarding the description in the latest judging guide. No reason to get silver paint out on an L78 when the intake is aluminum.

[Wayne M.]

Re: 65 396 intake manifold bolts

Jody & Rich -- I wasn't going to post these 2 pics, but I have these two A-mark manifold bolts (can't remember where they came from). One has a touch of orange remaining. (notice the thick integral washer). The threaded area (IMO) shows black phosphate. Harder to tell on the bolt heads because of some rust.

Now I have a mid-May '65 396 (not IF, but LF, 325hp with cast iron manifold). Very original; paint, etc. All bolts are 'FP' and all are painted, of course. But the paint is chipping off in some areas (like Jody's), and I can't say that the exposed metal looks like it is black phosphate; seems lighter.

This engine would have been assembled in parallel with Corvette blocks at Tonawanda during the same time period [T0607LF, June 7th]. It's hard to imagine that they used one kind of manifold bolt for IF blocks and another for blocks with cast iron manifolds. More likely they installed whatever the stock boy dumped into the bins.

[Rich P.]

Re: 65 396 intake manifold bolts

Wayne,

I have some A and FP bolts with what look to be black phosphate and all of those came off of steel intake manifold big blocks that were painted orange. But I know that I also have some originals that were cad. I know that I have seen cad/zinc bolt turn black over time (not saying this is the case here). but this is interesting.

Rich

[Jody B.]

Re: 65 396 intake manifold bolts

Rich & Wayne,

Back to the judging guide; even if the bolts were black, why would you paint them silver knowing that they were about to become orange due to engine painting? I don't see any reason for silver paint being mentioned on L78 intakes.

[Rich P.]

Re: 65 396 intake manifold bolts

Jody,

like I said in my earlier post It seems that someonre just accidentily put that there thinking it was for a small block. I have never seen a 65 66 or 67 big block Aluminum intake sprayed silver.

Rich