Quick SBC cylinder head question

nuch_ss396 · #1 04-20-2009, 01:53 AM

I've got a fast question for you knowledgeable small block
Chevy guys here.

Back in the mid-1970's I was helping an acquaintance pick
up a Hi-perf small block from a wreck yard. It was reported
to be an LT-1. The odd thing was that it had angle spark
plugs and I believe the heads were actually aluminum. I'm
not sure about that as I may have gotten this situation
confused with other engines purchased back then.

Simple question is: Did GM make an over the counter angle
plug head back in the early to mid-1970's? Were they available in aluminum?

I don't know why this popped into my head but it's bugging
the crap out of me. Can anyone verify the existence of such
a SBC cylinder head back then?

Nuch

x Baldwin Motion · #2 04-20-2009, 02:49 AM

anything can be made by a good machinist...

http://www.nastyz28.com/forum/showthread.php?t=45942

ten year old thread discusses GM performance Alum heads.
http://www.chevelles.com/forums/arch...p/t-43226.html

**Salvatore** · #3 04-20-2009, 02:56 AM

Angle plug heads were over the counter from GM about 1972 or so. They were the original turbo heads I believe. I bought one of the first sets from Shaws Speed Shop about that time. They ran very good and were cast iron.

Schonyenko2 · #4 04-20-2009, 07:28 AM

Some of the early angle plug heads had the same double hump casting, and were 186's. Cronkleton has a set of those on his blue deuce. If I remember the turbos were 292's.
Neither were aluminum.
Both were OTC.

**Charley Lillard** · #5 04-20-2009, 07:38 AM

I have a set of aluminum ones going on my 67 Z and a set of iron ones somewhere. The alum ones have have 0 part # stamped in them though making them experimental.

**Stefano** · #6 04-20-2009, 08:15 AM

I bought a set from Shepherd Chevrolet in the late '70s. Put my first multi-angle valve job, per the GM performance manual on them and fitted them with 2.05" Intake valves.

They were iron heads. I don't recall the casting number.

They performed great on the top end up to 8,000 rpms and allowed for plug changes with the headers much quicker.

**iluv69s** · #7 04-20-2009, 02:47 PM

the 292 "turbos" were angle plug.....they also made a 492 which was angle plug also I believe...both these were steel....I also have a set of angle plug o-dash part number alum chev. heads, but they are from 1963 I believe..then there is the "hemi" angle plugs from 69 which were aluminum. What heads do you have Charley? What year are they?

**Charley Lillard** · #8 04-20-2009, 05:42 PM

Mine have bolt holes on the end of the heads but I don't remember if they have dates. They aren't here to check. Part # is stamped on the end of each head.

**Charley Lillard** · #9 04-24-2009, 05:58 AM

I did find I have a set of Bowtie angle plug heads if anybody needs them. The Bowtie heads came later than the 292 turbos.