Back to the Future In a 1966 Fairlane GT
How fast can a (mostly) original 390 GT go?
Owner/ Alan Estergomy -- Message Board Below
Before I could answer that question, I needed a car. A car that was VERY close to
original stock as possible, including exhaust manifolds, carburetor and of course, heads
and intake.
My search brought me to North
Carolina where a guy was selling just such a car.
They only deviation from stock was a cam of unknown
origin but was
felt to be very similar to the factory hydraulic cam
and 3.50 rear.
He said I could see a picture of the car if I could
log on to a web site.
Well, of all the coincidences,
it happened to be this very site.
Woodys Fairlane website AND the car was Woodys ex-Fairlane GT.
So I sent the man from N.C. the money and had the car
shipped
to me on Long Island, New York site unseen.
After driving the car for a few weeks, it was obvious that it needed a
few things before it would usable at the race track. The biggest
problem was the clutch. It chattered so it was replaced by a new
HD Centerforce clutch and throw out bearing. Everything else looked OK.
I made plans to go to the track and see what the car was capable of.
So, early in July,
I packed up lunch and tools and went to a quarter
mile track in Westhampton, NY.
After my first pass down the track, it was painfully obvious that the
chassis needed
some sort of traction bar. Wheel hop was very bad and
reflected in the 60 foot time of 2.54.
If you know anything about
racing, you will immediately recognize that 2.54 time
to be only
slightly better than pedaling your Schwinn.
However, I was a little
surprised to find that the run produced a very respectable
15.07 at
95.6 mph. This was actually pretty decent considering how much time was
lost to wheelhop. This time, by the way, compares very well
with road
tests of new, original 390 Fairlanes and Mustangs of that period.
With these promising results, I set out to get traction bars and address
other items that
I thought were potential problems.
One such problem were the valve springs, which
are routinely overlooked
for more exotic answers to performance problems.
The engine seemed to
hit a wall at about 4000 rpm, struggling to go higher and this was
consistent with weak springs, among other things. I brought the car to
a racing engine builder
friend of mine, Lawrence Racing Engines in
Westhampton, where he replaced the springs
with new high performance
springs from Comp Cams. My suspicions were correct,
for as we took out
the old springs, we checked them for tension. Most were at
about 55
lbs. on the seat. This is definitely no good and we could see evidence
of valve float on the top of the valve stems. Next up were the traction
bars
and I bought a set of Cal-Tracs traction bars and had them
installed.
So once again it was show time and my friend Jerry and I headed out to
the track
in late August. The day turned out to be very nice but a
little too warm
with temps about 84 degrees.
For pass #1, I wanted to see how the car would go just as it came off
the street.
With the engine still hot, I drove the car to starting
line and brought the rpm to about 2200
and let let the hammer down.
Wheelspin was easy to provoke,
but it did go better than the first day
out with a 14.80 at 95 mph.
60 foot time was improved to a 2.36, but
still not good.
For pass #2, I decided to remove the air cleaner,
spare tire and jack to reduce weight.
I also lowered the
rear tire pressure to 26 lbs. and went back to the staging lanes.
Leaving the line at about 2000 rpm this time, I eased the clutch out and
punched the throttle. The car picked up well and went a 14.42 at 97
mph now.
Still had far too much wheelspin though.
For pass #3,I bumped the timing up to 16 degrees BTC. I also removed
the power steering
belt to see if I could eliminate a parisitic loss
from the pump. Back out to the lanes,
I decided to try leaving with
less rpm. At the starting line, I brought the engine up to
about
1600-1700 rpm and let it rip. The car felt strong and crossed the
finish line still pulling in 4th gear. I picked up the time slip, which
read: 14.33 at 97.2 mph.
I was surprised to see the mph the same,
indicating the P.S. pump does not really consume
much in a straight
line. The e.t. was better and the car felt a little stronger in the mid
range.
The engine still feels like it lays down at 4500 rpm but not
as bad as before.
The first two passes, I shifted at 5000 rpm. For
this 3rd pass, I tried 5200 rpm.
I went back to my pit spot and thought about what to do next.
I decided
that traction was still a problem (2.23 60 ft.) and lowered the rear
tire pressure down to 20 lbs. Also, since the engine makes such good
torque down low, I thought I would try leaving at a very low 1200 rpm.
For pass #4, After letting the engine cool down for half an hour,
I was back in the
staging lanes. The track official soon pulled us out and I went
to the
starting line. As I staged the car, I hoped that this would be a
memorable run.
The pre-stage light went on and then the stage light
went on. I brought the engine
up to 1200 rpm. The starter flipped the
switch and the yellow lights began to come down.
At the last yellow, I
let it fly. To my surprise, the car just seemed to bite and off it
went.
When the engine reached 5200, I put my whole body into the shift
to second then did it
again for third gear. At 5200 rpm I pulled for
4th gear and enjoyed the top end rush.
It turned out to be a great run as the car had its best pass of the day
with a 14.16 at 98.3 mph.
Wow! I thought that is really good
for a original 390 GT . I have seen
360 HP GTO's with tri-power, open
headers and 4.33 gears only go 14 flat at 102-103 mph.
After a few days to evaluate the cars performance, I think the hydraulic
lifters are pumping
up and are preventing the engine from realizing its
true potential.
Since it has a non adjustable valve train, I can't
eliminate that problem so I think I am
going to get a set of adjustable
rockers and try again in late September.
I'm sure the engine will like
the cooler air as well.
If I'm correct with the valve train stuff, I'm
sure the car will dip
into the 13.9's at 101 mph. Now that's pretty
good for a stock,
full exhaust 390 GT, don't you think? I'll keep you
posted.
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