1970 3963512 Block Strange One

[nuch_ss396]

Bill,

Were the piston domes on these marine engines the standard 10.25:1 design? With oval ports, I would expect so.

[3macs1]

Steve:
I am not sure if it had a 6223 crank. I asked specifically on the dimpled rods and pistons and he told me the shop that is rebuilding it told him they were just standard oval port but the crank did not have to be cut and was forged.
Also the air cleaner never had a 345 hp or 390 hp decal on it, just 454 and that was original. It was a fully loaded impala that my grandmother remembers was a salemans demo with 2000 miles on it when they purchased it in early january of 70. So it was a early production.They wanted the big engine to pull a camper.
The car was loaded with air, ps,PDB, tilt, PS, PW, PL, rear defrost,8t,posi, fender skirts, delux belts,remote mirrors, etc.

[olredalert]

------You have me there, Steve. I dont remember what the pistons looked like probably because they were going to a dumpster anyway......Bill S

[nuch_ss396]

OK - high or low domes?

[nuch_ss396]

[ QUOTE ]
.....They wanted the big engine to pull a camper.... .

[/ QUOTE ]

OK, silly question time. Did the full sized cars come with
a towing package if ordered? If so, would that possibly
incorporate a 4-bolt block? I've never heard of this before
myself, but you never know.

Steve

[olredalert]

Steve,,,Definetly had low domes, if they had any domes at all. I remember thinking that a guy could run just about any gas with those pistons. Pacemaker had there own engine program of sorts. I believe they built them to have as much torque as possible while still using regular gas. These engines were painted metallic green and were prominently labelled as "Pacemaker 427s"........Bill S

[3macs1]

Steve:
The domes on the engine I just sold were 10.25 Hp pistons .
Interesting question on the towing package. The car definately had a GM installed hitch and wiring. There was a trans cooler also but I don't know if that was factory installed.
One thing for sure I will always drop the pan on any 512 block I run into in the future.

[nuch_ss396]

Joe,

No real need to drop the pan. Just look at the oil filter
boss ( side ) to see if it has the external oil cooling
attachment provision. All 4-bolt blocks had this.

Steve

[bigchevydaddy]

Are you sure this was the original engine? If it was a demo, it might have had the block replaced under warranty, and they replaced it with a 4-bolt. Years ago I lucked into a 512-casting block that came out of a "totally original" Caprice wagon. Turned out that the block had been replaced by the dealer early in its life. It had a CE stamping. All the internals were low-horse 427, but the CE block had evidently been in-stock in the parts dept. and that's what they swapped in as a replacement.

BCD

[3macs1]

Definately the original engine and it was not CE. That much I did check since I still have a bunch of big blocks and I wanted to make sure he was not getting the original 454 out of my 70 chevelle.Which is buried in the pile also.