55 HT project Page 16
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Continue Fitting March Performance (MP) Parts
to my LT1 motor
ATI sent the wrong hub for the revised crank damper
setup that I need....
My Camaro LT1 hub is on the right,
According to ATI that left hub is a blower drive hub
for a small block Ford, don't think I can get that to work here...
That's the Ford hub on the right in this pic....
Larger OD crank snout,
different drill pattern for the damper mount....
Here's the ATI part # on the hub....
Doesn't quite match the correct part # that I need
that is on the box....
ATI just had the wrong part in this box,
pulled it off the shelf and shipped it to me....
I had to ship the wrong part back to ATI first,
then they shipped me the correct part....
eventually they paid for the freight both ways...
The Corvette LT1 flanged hub is quite a bit longer than the Camaro hub...
But it has the correct hole spacing and drill pattern,
and the correct crankshaft diameter....
The damper bolted up to the new flanged hub, no problem!
Now to see how well it matches up with the March accessories system....
The ATI LT1 Corvette damper appears to be fully seated on the crankshaft snout,
but is not aligned correctly with the March Performance LT1 system.
Putting a straight edge across the damper face, it appears that the misalignment
is about 1/2", too much!!
The ATI unit will be pulled and measurements taken on the crankshaft
and on the ATI flanged hub to try to determine where the problem is.
Here are a couple of sketches I made to show what I was finding...
The first (top) sketch assumed the flanged hub was all the way on....
So I pulled the hub off of the crank snout and took some more measurements....
It turns out the hub was not on all the way, still needed another 0.475" to go.....
I needed a longer bolt to help pull the hub all the way on the hub,
adding spacers as it moved into position, I used one of these bolts
from this puller, as it was the correct thread to match the crankshaft
snout thread, and started pulling the hub further onto the crankshaft snout...
The short bolt was the same length as the longer bolt when I started.....
but it broke off inside the crankshaft snout....
This tells me two things, one, that I have too tight an ID on this ATI flanged hub,
as the other ATI flanged hub I have, the one for an LT1 Camaro application, goes
onto this crank snout with no problems, and is definitely not as tight a fit as this
hub is showing....
And, now I have to remove this ATI damper and remove the broken bolt
from the crankshaft snout....
However, while trying to pull this ATI hub and damper off of the crank snout,
the threads on the puller bolt stripped, so that ATI hub is definitely undersized!!!
And I'm shopping for a new puller....
Found this on the ATI website....
There were no instructions that came with the "Super Damper"
But I'm glad I found this bit of info...
Got the damper off of the crank snout, it was really on there tight,
then drilled and removed the busted bolt stub with an EZ out...
Here's the bolt that busted off, and it is a grade 8 bolt...
Quite a few hours with #100 gray wet/dry sand paper,
then smoothing with #600
took out about 0/0008" to 0/0010"
then did an assemble with just the flanged hub and assembly lube....
No Problem....
Used these six screws and pulled the balancer on a little at a time
using all six screws, one turn each....
Once the balancer was snugged up nice and tight on the flanged hub,
all the screws/bolts were pulled off and reinstalled, retorqed, with blue locktight....
The belt went on nicely, everything lines up as it should now...
Except the power steering pump, just below the alternator,
it sticks out just a little, about an 1/8"....
More Later
