396 Intake Manifold Bolts

[Joseph T.]

I am assembling my 1965 396 engine and I seem to have extra intake manifold bolts, but not enough of one type. I have a few indented hex head with M's and F's and some regular hex heads with A's and M's and ur's. Some seem to have been zinc plated and some were black phosphated. Can I mix and match the indented hex with the regular bolts and what would be the most commonly accepted. I know what the JG says, But I am interested in what has been observed by Judges and owners. Thank you in advance for your responses.

[Wayne M.]

Re: 396 Intake Manifold Bolts

I am assembling my 1965 396 engine and I seem to have extra intake manifold bolts, but not enough of one type. I have a few indented hex head with M's and F's and some regular hex heads with A's and M's and ur's. Some seem to have been zinc plated and some were black phosphated. Can I mix and match the indented hex with the regular bolts and what would be the most commonly accepted. I know what the JG says, But I am interested in what has been observed by Judges and owners.

Joseph -- you say you're familiar with the '65 TIM&JG, which says "known originals use recessed hex with 'FP' headmark, or flat hex with 'A' headmark, (both styles) with 3 radial lines".

But then I get confused. Are you saying you have none of the known original types, or are just missing a few and want to know if you can use "not-known" originals to make a full set of 16 ?

My early June assembled 396 has at least 13 as 'FP' type; the others I can't see easily when installed, but I make out a dot in the middle of one (so that one will be replaced with an 'A' type that I have, if I get serious).

If at all possible, I'd stick with the 2 types observed. Maybe they assembled these blocks with a worker on each side, pulling bolts from their respective supplies. So I guess it could go 50/50 at the extreme.

[Jaime G.]

Re: 396 Intake Manifold Bolts

I agree with Wayne. My june assembled 396 has approximately the same
ratio of bolts as his. Maybe that was in the bin when these engines were put together. The assembly date for my engine is june 23. I would stick to these two types of bolts.
Hope this helps
Jaime

[Joseph T.]

Re: 396 Intake Manifold Bolts

Please let me clarify my point. Is it okay to mix the indented hex-head bolts with the regular hex head bolts as indicated by my photo or are these bolts incorrect for attaching the intake manifold of the L78? I also have M bolts that resemble these A bolts.

[Grant W.]

Re: 396 Intake Manifold Bolts

Hi Joseph
The bolt on the right is for 68 to 70 and 71 B/B aluminum intake. The bolt on the left is bellhousing for 68 to 70 SB and BB. I would stick with the M or F ones shaped like the right A bolt for your car. I've been collecting lots of bolts so I have a feeling I maybe correct. Thanks, Grant

[Bill W.]

Re: 396 Intake Manifold Bolts

# 16120 came with cad. plated flat "A" bolts with the thick washer . I have removed the thin washer "A" bolts from early iron intake 396s. Bill

[Wayne M.]

Re: 396 Intake Manifold Bolts

# 16120 came with cad. plated flat "A" bolts with the thick washer . I have removed the thin washer "A" bolts from early iron intake 396s. Bill

Bill -- are the 2 bolts on left side in this pic the thick integral washer 'A' type that were on your L78 (although these not cad) ? And is the bolt on the right the thin integral washer type ? Had a hard time reading the head marking on it but it seems to be RBM, clockwise, depending on starting point.

[Bill W.]

Re: 396 Intake Manifold Bolts

Yes Wayne . my bolts look like your bolts on the left. The rt side bolt is hard to see but it looks like a thin washer. Mine had good cad plating left on the bottom of the threads. The left bolt in Joes photo looks like the iron intake bolts I have removed.Bill