Hot Rod Forum : Hotrodders Bulletin Board - View Single Post - vortec head modification for .480 lift
View Single Post
  #28 (permalink)  
Old 09-30-2011, 09:30 AM
cobalt327's Avatar
cobalt327 cobalt327 is offline
Last wiki edit: Intake manifold
Last journal entry: 1980 Malibu Wagon
Last photo:
Join Date: Mar 2009
Posts: 5,031
Wiki Edits: 1616

Thanks: 128
Thanked 616 Times in 565 Posts
It's hard to tell exactly, but looking at his photo below (from the thread I linked to above), the top of the locks do look to be protruding a bit more than usual from the 3100 retainers. If that is the case, the ID of the 3100 retainer may be smaller and this will reduce the I/H of the spring- but I don't know what the 3100 retainer design will give for an I/H when used on the Vortec head, w/11/32" locks. For all I know, the 3100 retainer and the 11/32" locks might have a combined I/H of 1.8" or more- I can't tell from Spin's posts what's up w/that.

But- in ANY event I would have serious reservations using a set-up that didn't provide full engagement of the locks into the retainer's ID. I'd like to have a 3100 retainer and locks to measure. Just by looking at the 3100 locks should show easily if they're the same or thicker than the 11/32" locks- which they'd have to be (thicker that is) to work on a 8mm stem, yet have the same OD as a 11/32" lock.

It looks like what may be needed here, is a lock designed for the 3100 retainer's ID and the 11/32" valve stem's OD- unless that would make the locks too thin to be stable.

Last edited by cobalt327; 09-30-2011 at 09:38 AM.
Reply With Quote