heat riser

[jtabo@xxxx]

Hi All Again,
I'll try this one again. Has anyone out there worked on a 413 
exhaust/ram intake system? 

I'm in the process of final assembly of my "F" engine and am a bit puzzled 
with the exhaust heat riser valve and thermostat. Can someone straighten me 
out?
Should the valve plate be larger than the bore ( only in the direction 
perpendicular to the shaft, obviously) so that it provides it's own stop in 
the closed position and can only rotate open either by exhaust pressure or by 
relief of spring tension when heated? Does the counterweight rest on it's 
stop when the valve is open or closed?
I think I have all the parts for this thing but the valve plate I 
received is smaller than the bore by about 1/8" all around.

Thanks,
John Roth