> Moss's web site says this:
> "Triple exhaust springs were used on TR2 thru TR4 CT21470E. Special
double
> spring sets may be supplied instead for this application. Double exhaust
> springs were used from TR4 CT21471E on and all TR4As. While complete head
> assemblies are interchangeable, spring sets are not."
Hmmm, I didn't know the spring sets were not interchangeable. The only
reason I can think of is that the later "double spring" heads had smaller
ods on the exhaust guides (as well as smaller id), and so the pedestals
would not fit properly. But I don't know why the later double spring sets
could not be used on an earlier head. Does anyone else know ? Did the
"double spring" heads have a pedestal machined into the head ?
> Which brings up another question: is there anyway to tell if the
> extra engine
> I bought by itself is out of a '66 TR4 or a TR4A?
I believe the engine number should tell you, but I don't know the change
point.
> You have greatly eased my mind, I will put the triple exhaust
> springs on the
> exhaust valves. I only found the pedestal collars on the exhaust
> valves on
> the TR3A motor, but not on the TR4 motor- is this correct?
The triple springs always used the pedestals, even on the earlier TR4 with
triple springs.
Randall
|