L72 "gusseted" block (3869942)

[E S.]

Did not see anything in Archives about this- Curious about when the 427 "gusseted" block stopped?
TIMJG states approx. vin 1700; I have vin 3795 with gussets-Like to hear from other L72 owners (and L36)
Thanks
E.J.

[Mike M.]

Re: L72 "gusseted" block (3869942)

the 1700 vin # in the judging manual comes from me, i had such a block that came out of 17XX vin 66. mike

[Patrick B.]

Re: L72 "gusseted" block (3869942)

the 1700 vin # in the judging manual comes from me, i had such a block that came out of 17XX vin 66. mike

Mike-- Was this a 962 block bored to 4.25 with the casting number ground and stamped 3869942, or was this cast as a 942 using the front part of the 396 mold with the gussets over the timing chain cover? What was the casting date. I think the earliest 942 block I have seen was about I-20-5 and I didn't notice any gussets if it had them.

[Mike M.]

Re: L72 "gusseted" block (3869942)

pat: i sent you a PM. it was a 942, with gussets and on the rear wall of the front of the block it was embossed 962. the casting # was unmolested. this engine came out of early 66 corvette, 4 bolt main 425HP based on the pad's stamping. i can't remember for sure what the casting date was, but it was early in the fall of 65 best i can recall. mike

[Patrick B.]

Re: L72 "gusseted" block (3869942)

What is the casting date of your block E.J.?

[E S.]

Re: L72 "gusseted" block (3869942)

Patrick- Mine is Sept 2 1965 (I25)
E.J.

[Patrick B.]

Re: L72 "gusseted" block (3869942)

Patrick- Mine is Sept 2 1965 (I25)
E.J.

Certainly very early.

[E S.]

Re: L72 "gusseted" block (3869942)

Mike- I was curious-Were the "gusseted" blocks used randomly during the year, or were they "phased out" at a certain point?
Also- Were the 2-bolt 942 blocks also gusseted? (Nothing in Alvin Colvin's book either)
Thanks-E.J.

[Mike M.]

Re: L72 "gusseted" block (3869942)

I'd guess the gusseted blocks were early 66 usage only. I doubt they were used randomly up till 67's hit showroom floors. I havent ever seen a 66 390 gusseted block but then again, I've only seen the block I had and 2 or 3 three other gusseted block'd 66 when I was 66 team leader. I haven't judged anything other that 63-4's and an occasional 53-5, lots of 56-7's and an occasional 61-2's as well as lots of 65's. I think pat boyd has sen one or two gusseted 942's. regards, mike mccagh

[Patrick B.]

Re: L72 "gusseted" block (3869942)

Mike- I was curious-Were the "gusseted" blocks used randomly during the year, or were they "phased out" at a certain point?
Also- Were the 2-bolt 942 blocks also gusseted? (Nothing in Alvin Colvin's book either)
Thanks-E.J.

[E S.]

Re: L72 "gusseted" block (3869942)

Patrick- Understood-makes sense- I was just trying to get a feel for when the gusseted blocks were no longer used, and if they were used strictly or randomly until that point. Quite a few cars before, between, and after Mike's 17xx car, and my car 3795.
BTW- I have not had the intake off of my car, so I cannot comment on the 962 cast. # on the aft side of the fwd. bulkhead.
Off the subject, but your description of the sand casting process for engine blocks must be the same for exhaust manifolds. I have an excellent set of 3797901 and 3797902 (62 fi.) exhaust manifolds, and if you look carefully, you can see "mold segment lines" on the fwd. and aft. ends of each manifold that could be interchanged for various engine horsepower or accessory specs.
Thanks for the reply and the good info. E.J.

[Mark F.]

Re: L72 "gusseted" block (3869942)

https://www.youtube.com/watch?v=ziVhj2oifl0

[Patrick B.]

Re: L72 "gusseted" block (3869942)

Mark---- Thanks for the link to the Ford Foundry you-tube. They didn't show the patterns, but they showed a lot of detail of the sand cores produced from the patterns and the pouring of the iron into the molds created by the patterns.

[Gary B.]

[Mark F.]

Re: L72 "gusseted" block (3869942)

Mark---- Thanks for the link to the Ford Foundry you-tube. They didn't show the patterns, but they showed a lot of detail of the sand cores produced from the patterns and the pouring of the iron into the molds created by the patterns.

Thanks, Patrick (and Gary - I don't know how to "double-quote" in a reply?)...

For high-production parts, to the best of my knowledge the wood patterns (which BTW were real pieces of art and craftsmanship) were the MASTER dimensioned and approved part that was then generally used to create corresponding tool-grade steel dies. Those dies were then used on the line to imprint the cope and drag features of a given block casting - prior to insertion of the various sand cores necessary to correctly shape the part. I never saw a wood pattern used on a production casting line during my visits to Ford casting plants ('77-'81). I was in Cleveland Casting more than any other - Windsor Casting; Michigan Casting Center; and Dearborn Foundry to lesser degrees.

I would imagine the wood patterns would have been initially used to mold and validate the resulting cast part. The pattern could then have been adjusted as-necessary before spending the money to have those tool-grade steel dies made, but that was outside of my bailiwick. Also, I can imagine the same thing could have happened for very low-production, and/or custom special castings...but I'm speculating on that and have no direct knowledge in that regard.

It's a rainy day here in Pittsburgh and I have found a few more very interesting videos on casting processes...it's weird, though I have not found any GM-related videos on casting, machining, or anything of that sort??? As far as I'm concerned, I don't think that's a big deal, though - casting is casting - the processes are rather primitive in nature - but I don't think they varied greatly between any of the Big 3 (at least not back then).

I may create a separate post with some links (including the Windsor one here) if you guys think that might be a way others could see these, too? What do you think? thx, Mark