enginjoe

iTrader: (11)

Edit: Ordered some lunati duals with everything. Thanks for all the help guys. I'll post how it turns out.

RonSSNova

iTrader: (3)

Ah. good deal! It will go back together correctly now!

Ron

enginjoe

iTrader: (11)

No dice. Valves are thicker than 8mm, so retainers and locks don't work.

midevil1

iTrader: (17)

So you have standard 11/32 valves. These are aftermarket castings?

ZeeOSix

When you measure the installed spring height, it is simply the distance between the spring's bottom surface to the spring's top surface when the spring is installed and the valve is closed.

So that means all shims and the retainer & keepers must be in place. The special adjustable (micrometer) measuring tool just sits in place of the spring, as you can see the retainer and locks in place when the tool is used, as shown in the photo in Post #15.

vettenuts

iTrader: (4)

Can you pull a valve out and measure it? Sounds like they fitted SBC valves into the head along with the springs. These may be heavier and the reason for the larger springs and higher seat value.

enginjoe

iTrader: (11)

^This. I didn't pull it out, but I measured the valve stem width and it was 11/32. The guy I bought them from said they were bigger valves (2.055 intake valve and 1.60 Exhaust valve). I used a micrometer with the seat and shims installed using the retainer; the installed height was 1.8.

They are stock 241s that have been worked over. After doing some research, these must be some really early LS1 heads. This is the kind of stuff people did before LS1 aftermarket kicked in. Now that they have been machined for these kind of valves, I'm wondering if I could put LS1 stuff in there. I guess they could be run as is, with some shims, but with the heavier valves, I'm not thinking it could rev as high.

vettenuts

iTrader: (4)

That may be why the bigger springs with a larger seat value were installed.

BigMilan312

iTrader: (1)

Buy some YellaTerra rocker arms, those should solve it