69 DZ Blocks

[HOT3O2]

Yes your probably right Sam. The quality control back in those days is not what it is today.

[crobjones2]

My late November (68) built L48 is a 388 block. I also have a L48 block from a 69 full size wagon that is a 388 2 bolt main.

John

John
Are both your L48's from theTonawanda plant?

[Boston14]

My 11D (68) L48 is a 388 block also. It is a Tonawanda cast and built engine. T1120HB

boston14

[JKZ27]

Chris,
I know the one in my 12B SS is, I'm 99% sure the other one is too but I'll check tomorrow.

John

[JKZ27]

Yes, the other block is a Tonawanda. Strange though, looks like the cast date is I 26 8 and the assembly is T0212HN.

John

[crobjones2]

it appears that only the Flint assembled motors using this block  were 302s while the Tonawanda built motors are of the 350
I am curious if your blocks are 2 or 4 bolt? Mine is a 4 bolt

Kurt/Ed/John - does the above statement follow what is in the database?

[KurtS]

Chris,
Good observation, supported by the db. Also realize that Flint sometimes didn't make many of certain suffix codes, so that distorts it some.

[Boston14]

My 388 Tonawanda block is 4 bolt also. Tonawanda did not have the machines needed to produce 2.02"  intake valved heads, so they did not produce any 302 engines (at least that I have ever heard of). John Z or Kurt correct me if I am misinformed.

boston14

[jdv69z]

So was the 388 block cast at Tonawanda? And shipped to Flint? Or cast at both plants?

Jimmy V.

[tmodel66]

My 388 Tonawanda block is 4 bolt also. Tonawanda did not have the machines needed to produce 2.02"  intake valved heads, so they did not produce any 302 engines (at least that I have ever heard of). John Z or Kurt correct me if I am misinformed.

boston14

Could you explain this.  All it takes is a different fly cutter to put in seats. The guides were the same size. The castings were basically the same in configuration.

[Steve Shauger]

My 388 Tonawanda block is 4 bolt also. Tonawanda did not have the machines needed to produce 2.02"  intake valved heads, so they did not produce any 302 engines (at least that I have ever heard of). John Z or Kurt correct me if I am misinformed.

boston14

This issue was discussed several years ago. I recall a few orig 302's built with the 388 block.

[KurtS]

Could you explain this.  All it takes is a different fly cutter to put in seats. The guides were the same size. The castings were basically the same in configuration.

The chamber had to be clearanced for the flow. Tonawanda didn't have that tooling/station.

[JohnZ]

<<Could you explain this.  All it takes is a different fly cutter to put in seats. The guides were the same size. The castings were basically the same in configuration.>>

Photo below is a 461 chamber with 2.02/1.6 valves, but it's similar to the 462/291/186 chamber; note the added machining cut to unshroud the side of the chamber wall adjacent to the intake valve to optimize flow. Tonawanda only built small-block heads with 1.94/1.5 valves and no unshrouding cut, and didn't build any solid-lifter small-blocks; all solid-lifter small-blocks (and hydraulic-lifter L-79's) used 2.02/1.6-valves, and they were built only at Flint V-8. Flint had the transfer line station for the larger valves and the unshrouding cut, and Tonawanda didn't.

[tmodel66]

Thanks Kurt and John. Forgot about the chamber cut. I was thinking in terms of machine shop work and not assembly line work which is apples and oranges. Every step has it's own tooling.

[L78 steve]

There was also machining under the valve so not to neck down the flow on the 202's