[TR] TR4A valve springs

[fogbro1 at comcast.net]

Listers, 



For those who care about such things, the later TR4s and the TR4As used identical double spring sets on the intake and exhaust valves. But we all know that. What doesn't seem to be widely published are the dimensions of those springs. They are: 


Outer Spring 
3-1/2 working coils 
Free length  1.67" 
Solid length max 1.052" 

Inner Spring 

ID .648"  +/- .005" 
Free length  1.63" 
Solid length max 1.02" 

The dimension of the machined recess around the base of the valve guides into which the springs fit apparently remained the same as that of early cylinder heads : considerably greater than o.d. of the above outer spring. 

So the cylinder head I have on hand has proven to be a TR4A head (confirmed by Terri Ann's web page and Ted Schumacher) and the springs and collars I purchased are correct, even though they did not appear to be so. On with the rebuild! 

Ed Woods