Re: ZL-1 & L-88 head design clarification
According to Colvin, there were 3 #'s starting in '67 that had this "half moon" casting mark, all square port, hi perf applications. (Mechanical lifters).
The first was '67 only, #3904391, and had no temp sending unit.
The 2nd was the #840, and was installed in '67, '68, and '69. It was also cast in '69 as a #291, with a tapered spark plug seat. The #291 was also used in '70, since the 512 block was used in '70 for the 454. The only difference was the crank being stroked for the extra cubes.
The '67 L88/9 aluminum heads (#392) was identical to the #840, except for the casting metal.
__________________
COPO 9561/9737 M40 X11D80
13.37 @ 105.50 on pump gas,drove it to NATL TRAILS and back [email protected] SCR22
|