[TR] TR4 radiator Progrees report

[Randall]

> It was not cheap to have the radiator recored with the hole, 
> not an easy job.

That's odd.  My radiator guy said it was no problem and would only add $25
or so to the cost of the recore.

> purchased one that
> pushes through 1000CFM.

Is that free air, or with the restriction of the radiator?  Not unusual for
the flow to drop by 20% or more when there is a radiator involved (and what
good is a fan without a radiator?).

> I have done a bit of research on the internet but can't decide whether
> removing the fan hub extension will upset the motor or 
> whether the plastic
> fan had already done that.

The fan extension should play no part in balancing the motor.  The original
weights were to balance the fan & extension, not the motor itself.  There is
a school of thought that says the original metal fan & it's rubber bushings
provided some measure of harmonic dampening; but deleting them on a
street-driven motor does not seem to be a problem.  I've been running that
way for almost 30 years, and never broken a crankshaft.  If you are going to
be turning over 5000 rpm for any length of time (eg racing), then it might
be wise to add a dampener.

But it is important that the pulley hub be firmly clamped in place.  I wound
up having to make a special clamping piece that would reach around the end
of the crankshaft nose and bear only on the pulley hub.  Even better would
be a larger piece that fills all the way out to the bolts for the pulley
halves, which I believe is available from several vendors.

-- Randall