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It's
been a while since we've updated you on our big-block project car,
but rest assured the FE 428 powered Mach 1 has not been sitting
idle. In fact, after several months of bracket racing virtually
every weekend, this car is still just getting optimized. The 428
had no problems running solid 11.80 passes at 117 mph, but we felt
that something was holding it back. You may recall that shortly
after the 428 was broken in, the solid flat-tappet camshaft we had
spec'd out for the motor bit the dust. We pulled the cam and realized
the intake and exhaust lobes for one of the cylinders were wiped
flat. The damage was so bad that one of the lifters had a hole worn
completely through. It seemed
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The
Crane solid flat-tappet lifters are suspected to have hung-up
in their bores, resulting in excessive friction and a wiped
camshaft. |
obvious
that the lifters for whatever reason had failed to spin in their
bores, resulting in accelerated wear. We sent the failed cam and
lifters back to Crane for analysis. Their testing indicated the
hardness and taper values on the cam lobes and lifters were within
specifications, and they suspected that either some machining debris
in the lifter bore, or possibly even a off-center lifter bore, resulted
in the lifter "freezing" in place and thus flattening
the cam lobe.
In the meanwhile Victor had already replaced the mechanical cam
with a Crane hydraulic cam of similar specifications (253 degrees
duration at 0.050", and .585" lift.) Although we had look forward
to the rpm potential of the solid, for now the hydraulic would have
to suffice. |
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Emerald
put together a 4000 stall converter to match the 428's power
band. The result --see below! |
The
428 responded well to the hydraulic cam, with solid 11.80's and
eventually low 11.70's. However the sixty-foot times seemed slow
for all the torque the 428 should have been putting out. The best
the car could manage on slicks was in the mid 1.70's. We theorized
that the cam needed more stall speed in order to get the car off
the line with the engine in the peak of its torque band. The 3000
stall converter that was in the C6 was probably falling about 1000
rpm short.
With our recent positive experience with Emerald
Torque Converters, we decided
to have them put together a converter to back the FE. Emerald's
converter guru Gary Mladinich studied the Mach 1's specifications,
then suggested a 4000 stall donut. A week later Victor had the converter
swapped in, and the Mach 1 was back at the strip. |
The
result- how about nearly four tenths off the ET, and three miles-per
at the eighth?!
The 428 clicked off back to back sixty-foots in the low 1.60's,
and responded with an impressive 11.39 ET. By the way, if you're
wondering if this car is NHRA legal to run in the 11's, don't worry...
a six-point roll bar was installed recently, and we'll have a full
write up soon.
What's next?
Project FE still has room for improvement. In fact we think
by giving the solid flat-tappet another shot, and possibly experimenting
with Dove's FE intake, we should get a solid high-10 second car.
So now, who say's FE's are slow? F/M
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Go
to Project FE: Part 1
| Part II | Part
III | Part IV |
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