|12-24-2008 07:17 AM|
Thanks for the info guys. I know for sure the casting number starts with a 387 not 397 and they do have 1.94's and press in studs. I had a book a long time ago that told what they were but it's long gone and Mortec don't show them.they have sunken exhaust valves so their early non hardened versions and luckily no cracks.Thanks again
|12-24-2008 12:41 AM|
From what I remember the "487" and "487x" heads are fairly sought after by lower end circle track racers. I know when I raced in a Street Stock class they were the most commonly used head out there. The guys who ran them paid pretty good money, so they must be one of the better GM castings *Bowties, and Vortec" were illegal. I never did come across a set while I was in that class, so I can't tell you from experience though. We always ran 305HO heads.
|12-23-2008 10:10 PM|
3973487....71-72...350..........1.94/1.5 or 2.02/1.6 valves, was also used on '71 350/330hp LT1, 75cc chamber
3973487X...71-72...350..........1.94/1.5 or 2.02/1.6 valves, 75cc chamber
If your heads have a 1.94" intake valve and pressed in rocker studs, they did not originate from a Z/28 -LT-1 motor.
One of the better of the smog era heads. Check for cracks reguardless.
|12-23-2008 09:32 PM|
SBC Head casting number 3873487
Hey Guys i've got a set of heads casting 3873487,I know for sure this is the number because i blasted them.It seems like i read a long time ago that they were Lt1 heads from the early 70's but i don't know.Does anyone out there have any info. It would be appreciated