Sigh, if its such a simple engine, why is it so complicated??? ARGH
All I want is an engine for my TR3 that I can wind out on mountain roads and run
occasional autocrosses in. But of course, if a little modification is good, more
is better and too much is just right. And over my head gets real expensive!
I'm raving my frustration. Let me try to make more sense and try to take a
shallow dip into rationalty...
I'm getting my TR3A engine rebuilt & making a few minor performance mods. My
philosophy with engine rebuilds is that if its worn enough to rebuild, its worn
eough to replace just about everything. The block is old, as are the crank,
rods, head, and flywheel. Everything else is new (ending up with a lot of good
used engine parts left over).
About the minor tweeks going into the engine:
Hepolite 87mm pistons & sleves
280 degree cam (3/4 race grind)
external oil cooler (installed that before the rebuild)
cast aluminum valve cover & sump (makes it go way faster :*)
special rocker arm pedistals that support the end rocker arms
springs on rocker shaft replaced with sleves to eliminate latteral movement
stronger studs & nuts for holding down rocker arm down
Stronger head nuts
.060" milled off the head
polished intake and exhaust ports and valve pockets
hardened seats on both intake & exhaust
oversize intake valves
shrouding removed from around the intake valve
combustion chambers polished
shortened push rods
duel valve springs and alloy retainers
Harmonic dampener on the crank
lip type rear seal
header
duel DCOE45 carbs
Braided fuel hoses & Earl connectors
Electric fuel pump
fuel pressure regulator
Electric fan
You know, just the normal little fashon accessories a girl likse to add to an
engine.
Well The engine is at a reputable automotive machine shop having the normal
things done, ranging from fitting new small end bushings and fitting wrist pins,
to having the crank ground .010" and the engine balanced.
To assemble the engine, the sleves will require beveling to match the head. I
have no idea how to correctly go this. I'm also not too sure about setting the
spacing on the thrust washers for the crank. Well I decided that I wanted
everything perfect in the engine since I expect ot occasionally give it some
hard use & high revs as well as long distance touring. When I think of building
the TR 4 cylinder engine I think of Greg Solo (He personally builds engines for
a number of racing Morgans including the locally famous baby Doll that has this
habbit of giving small block 'Vettes fits on the track).
I called Greg yeaterday and asked him to build my engine up to long block for me
and to do the inital set up on the DCOEs(The Morgan Sports model come with
DCOEs). I told him what I was having done in the machine shop. I was suddenly
hit by the clearence perfectionist lines (which is of course why his engines
work so well and I want him to do the work). Immediatly he suggested that I
needed to get the grank nitrited to work with the cam without breaking (The TR
crank has this habbit of breaking at the flywheel end above 5000 RPM & the cam's
power curve goes to 6000 - which is why I went to a harmonic dampener) He said
that nitriting adds about .003 to the crank & needs to be accounted for when
grinding a crank, and the radiusing on the bearing surfaces has to be correctly
maintained for proper oil flow (I had heard this before in reference to the TR
crank). He said the plugs in the crank need to come out for proper passage
cleaning & if in place when a crank is nitrited will never come out afterwards.
he also said that he will not warrentee the work if the machined clearences do
not meet his specifications. He wants to do a trial assembly check all
clearences and if there isn't enough between valve & piston to get the pistons
turned down slightly (!??!). This one confused me a little. Kasner's book on
racing TRs mentions .102" milling provides optimum reliable performnce for the
engine (11.6 to 1). In a section for street tuning, he mentioned taking off
.090" to bring the compression up to 10.2 to 1. I figgured that .060" would be
a conservative compression increase thay would probably put me in the mid 9 to 1
ratio (remember there is a shroud around half the intake valve that gets
removed, decreasing the compression). The book didn't mention valve clearence
problems with this.
Well, Greg managed to talk me out of having the machine work done at my local
shop. I figgure if I let him do it his way, it will be more expensive but it
would be exactly right. Of course now, I suspect he ends up with more money
this way, but I end up with some warrentee protection & peace of mind that it
was done right. I called the machine shop to turn them off. They were very
unhappy. I'll pick up the engine when the crank gets back from the grinder.
It looks like I'll have to pay twice to have the crank done :*(
Meanwhile, the body tub is over at a paint shop getting the tub repainted and
undercoated. I gave up trying to put final colour on a car sitting outside on
fine sand under two shedding oak trees with bugs attracted to new paint and cats
walking over it at night. Since the nititing process takes a few weeks, I
expect to have the tub back, the steering, hydrolic lines & linkage in by the
time the engine is ready. This will enable me to put the engine directly into
the car unstead of on a pallet outside with a tarp over it. Next house has to
have a garage! Next car is not going to need a complete rebuild!!
Why do I always make things hard on myself. 'Cuse its fun when it stopps
hurting and goes vroom.
TeriAnn
TeriAnn Wakeman Any thoughts expressed above are mine
twakeman@apple.com Unless they are worth anything. Then they
LINK: TWAKEMAN become the property of my employer.
408-974-2344 TR3A - TS75519L, MGBGT - GHD4U149572G, 109 - 164000561
TeriAnn Wakeman Any thoughts expressed above are mine
twakeman@apple.com Unless they are worth anything. Then they
LINK: TWAKEMAN become the property of my employer.
408-974-2344 TR3A - TS75519L, MGBGT - GHD4U149572G, 109 - 164000561
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