Hi, Folks,
So my new engine has accumulated around 1500 miles on it and I'm exploring
the upper RPM limits a bit in second and third gear.
The crank, rods, pistons, pressure plate and flywheel were all
balanced. New AE 87mm pistons were used. The crank was turned down .010",
and I had the cam reground by ISKY, and I have the TR 555 grind which was
supposed to be a 'fast road' cam. It has 268 degrees of duration. The
flywheel was lightened by a few pounds, but it still weighs a country ton
with the old-style ( many little coil springs ) pressure plate.
It runs quite well and pulls like mad from 1800-4200 rpm. I have an OD, so
I'm guessing I have the 4.10 rear end.
In my 20/20 hindsight, I would have done a couple of things different, and
I probably will when it starts raining some time in December. They are:
1) Shave the head to get the compression higher
2) Ditch the '4' flywheel and gone with a 4a flywheel or perhaps even an
aluminum one with a 'modern' diaphragm-type pressure plate
So briefly, that's the drivetrain.
What I'm noticing is that the engine is quite smooth until you get up to
around 4800-5000 RPM when a vibration sets in. I haven't tried going past
5000. It feels unhealthy.
In that article recently posted (
http://www.speakeasy.org/~mgendron/Kastner_TR4A.html ) by someone on the
list about Kastner doing salt flats racing and drag racing, he was pulling
six grand on his motors.
.....and Terry Ann Wakeman, who is also on the list, has a hot-rod TR3 (
see her nice web site at: http://www.cruzers.com/~twakeman/TR/index.html )
and I believe she has a harmonic balancing pulley on her car. I seem to
recall her saying once that she shifts at 5700 on on-ramps.
I'm jealous.
So here are my fears, questions:
When I had the motor balanced, the machine shop guy got a little beady-eyed
when I asked him if he had balanced the crank with the front fan extension
on the crank. I'm wondering now if that's the problem? It's a fair-sized
chunk of cast iron.
Or
Do these motors really need a balancing pulley to rev? Did Kastner have these?
Or
It it just impossible to make them rev with a 35-40lb flywheel \ pressure
plate combo?
What steps should I take to make 'er rev?
Once again, I'd appreciate any first-hand experience from the racers out
there.
-jeffrey
Jeffrey J. Barteet, System Administrator
National Center for Ecological Analysis and Synthesis
735 State St., Santa Barbara, CA
barteet@nceas.ucsb.edu 805.892.2508
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