block and journal question

[Charles M.]

Car is a 64 NOM. The block is on a stand but still mostly together. Block is a 3858174, found this number on drivers side top near bell housing, and I think cast C 29 6, found on passenger side in same place.
Some facts:
The heads have 1966 casting dates.
3858174 is generally considered to be a 1966-7 unit.
My pad stamp is F04I2HCH, thats all.

Questions:
Exactly where should I find the block casting date?
If this is a 66-7 crank in this 66-7 block will it be the large or small journal?
Isn't it most likely a 2-bolt main?

[Joe L.]

Re: block and journal question

Chuck-----

The casting date for small blocks is found on the bellhousing flange on the passenger side as you've found. "C 29 6" means March 29, 1966.

All pre-68 small blocks were "small journal" and that includes the block casting that you have.

ALL small blocks through 1968 were 2 bolt main bearing. No originally configured GM small block engines used 4 bolt mains until 1969 when all 350s with 4 barrel carb and 302s got them. No 265, 283, or 327 EVER originally had 4 bolt mains. They can be converted to 4 bolt main configuration using aftermarket-available parts. GM never made 4 bolt bearing caps for the "small journal" cranks. 1968 327s can be converted to 4 bolt using 1969+ 350 4 bolt main bearing caps, though.

[Mike M.]

Re: block and journal question

it'll be a 2 bolt main. its out of a pass car or truck based on no vin derivative. use the HCH suffix to determine exact application(i use old Motor Manuals to look up suffix). mike

[Charles M.]

Re: block and journal question

So far no one has found this suffix in a reference.

[John P.]

Re: block and journal question

The lime book shows the HCH suffix as a '66, 327ci, 275hp passenger car motor originally configured with a Holly 4B and powerglide.

[Tom D.]

PG '66 Pass Car with 327-325 HP ( if HCH) *NM*

[Tom D.]

Corrected to 327-275HP ( if HCH) *NM*