Introduction
This car is relatively heavy at 4,000 lbs and, with the stock 302 HO
and high-first-gear ratio AOD with the very low stall stock converter
and 3:27 gears, was weak on throttle response and especially low rpm
torque both in town and on the open road in climbing hills and passing.
(Beefed 4R70W & 2800 stall on the way, 3:55’s already in)
Having owned some serious muscle in bygone days, I yearned for more “under
the loud pedal.”
The car needed more power and torque so it’s performance would
match it’s visual image –
which I happen to think is still cool and definitely unique from most
go-fasters, not to mention it’s a great road car with all the bells
and whistles.
I got the opportunity to buy a 30k mile 95 Lightning roller shortblock
which I preferred because of the capability of using a stock type roller
cam and hardware, and it has the Ford heavy duty “football” rods
and dished hypereutectic pistons which would work well with my intended
compression ratio of around 9-1 and withstand some horsepower upgrades.
It came with the required 351 EEC-IV distributor, and as it was originally
a serpentine belt motor, the damper and crank pulley lined up with the
front accessories from the 302. It had no sign of a cylinder wall ridge,
so I just freshened it up with new moly faced rings, bearings, double
roller timing set, oil pump (the existing pump had nicks in the gears),
and heavy duty oil pump drive shaft. The cam bearings were fine. I took
all the galley plugs out, gave the entire block including the cylinders
and galleys a thorough cleaning and oiling, and reassembled the stock
shortblock. Being on a very tight budget, I could not afford to get the
block machined like I would have liked. That has to wait till it’s
393 time.
That budget also prompted me to gather parts over time, shopping for
good used parts or new parts leftover from someone else’s projects
at reduced prices. I was able to find nearly all major parts good used
or leftover. The major new parts included the shortblock rebuild parts
as listed above plus new ARP headbolts, all new sensors as the old ones
had over 225k miles, plus of course gaskets. I also sprung for a new
high performance water pump, high flow thermostat, Ford blue silicone
hoses – all of which fit except the bypass hose was too short – new
high performance cap, rotor and wires, roller cam gear for the distributor,
stainless bolts for everything external, and the 351 balance flexplate.
I got cheap chromed steel valve covers that were a little taller to clear
higher lift rockers, plus a new throttle body and EGR plate at Ebay,
and found a Trick Flow oil fill that fit the grommet hole in the valve
cover and had the fitting for the tube to the EGR plate. Overall I figured
about a 40% saving over new.
Virtually everything else was good-used or leftovers, from the swap pan
and pickup, 1.9 intake Edelbrock Performer pedestal heads (3k miles for
$600) which boosted the stock Lightning compression ratio from 8.8 to
about 9.2, 1.72 Ford/Crane roller rockers to boost lift from .444 to
.477 to compensate for the additional displacement, the hydraulic roller
cam (a stock 302 HO cam as it had the desired .050 duration for a streetable
power curve and torque peak, plus it was only $40 nearly new), the roller
lifters and hold- down hardware, the intake, the headers, the mass air
meter and injectors. My sources for the more critical parts like injectors,
cam, rockers, etc, were the classifieds on
www.corral.net and
www.stangnet.com.
I trusted eBay sellers for non-critical, non operating items like valve
covers and other small items.
UPDATE: After driving the car for several
thousand miles, I came to the conclusion that the
Mustang guys were certainly right about not using
too small a cam even in a relatively mild 351. Still
trying to live within some kind of budget, I opted
for a Trick Flow cam, just the Stage 1. It's 220
@ 050and around .500 lift with stock 1.6 rockers.
I made some inquiries and was told that it would
probably still clear my pistons with my1.72 rockers,
which also upped the lift to .538 & .548 - to
a non-Ford person that sounds like quite a lot, but
I'm becoming a believer that we have to think differently
than the other guys.
The valves cleared with room to spare. It idles just a tad rough (sounds
nice!) but does idle steadily at 800. The seat-of-the-pants-o'meter showed
a marked improvement in power across the board and I was amazed at getting
an honest 24 mpg on a long road trip thru hilly terrain at nearly 80
mph with a severely loaded car.
Would have been fun to go to the Stage II, but I'm sure that would have
overmatched my heads, intake, and compression ratio, and it really does
scoot pretty good from a punch at any rpm and at any speed. And I am
sooo happy with the mileage!
AND it's a bargain compared with other big name brand cams.
Parts You Will Need
I’ll now go through items that needed attention to complete the
swap.
As I said, my shortblock was originally equipped with a serpentine belt
setup, and came with the right damper and crank pulley so I didn’t
need the pulley and spacer otherwise needed for a v-belt engine.
The passenger side accessories bolted right up, although the alternator
ended up higher. This posed a problem with the radiator hose which, in
this car, normally runs over the top of the alternator. I solved this
problem fairly simply by cutting the radiator end off of another good
hose back beyond the second curve and splicing it onto the end of the
new hose with two clamps and a short length of exhaust tubing. That gave
me enough length and the right curves so I was able to route the hose
behind the alternator and around the passenger side of it. There’s
a picture of it
HERE.
The driver side accessories were a whole different matter. I don’t
know if the stock Lincoln PS/AC bracket is different than a Mustang bracket,
but I absolutely couldn’t figure out how to make the Ford 351 adapter
bracket work. There were probably simpler ways to solve it than what
I did, but I ended up with a bracket from an early 90’s 351W pickup.
That positioned the PS pump a little closer to the battery, but it did
clear. The AC bracket part of it took a different style compressor than
my '89, so I had to fabricate an adapter. It also positioned the
compressor high enough so I had to cut away a little bit of an underhood
brace, besides removing more of the insulation.
The front cover and water pump from a 302 will fit a 351, but as I mentioned
I went with a high flow pump. I learned that the water pump and front
cover from pickup Windsors will also work, but you have to have the matching
front cover to go with the pickup water pump as the passages where the
two meet are different than for a car setup.
I used new stock Lincoln Mark VII motor mounts, which are the same as
Fox Mustang convertible V8 motor mounts. They’re stronger than
Mustang coupe mounts and position the motor a little bit lower, which
turned out to be critical for hood clearance.
I had to get a 351 Fox swap double hump oil pan and pump pickup – Ford
only makes a 5 quart swap pan. I understand there were some cars with
351s and that type of pan, maybe Crown Vics circa 1990 (?) The only thing
to note with that pan in the Mark VII chassis is that the front swaybar
hit the front drain plug. I put about 1-1/2” spacers with longer
grade 8 bolts between the bar mounts and the frame which dropped the
bar just enough to clear.
For intake, I found a GT40-351 lower that I mated to an early Explorer
upper which is essentially the same as a Cobra intake. Other options
would be to use the upper from i.e. a 302 Edelbrock Performer on their
351 truck lower, or a complete Trick Flow 351 intake, or to use a complete
Cobra or Explorer intake adapted to the wider engine with either the
Weiand (Holley) spacers or the better but more spendy ones from
www.pricemotorsport.com.
Using a stock 302 HO intake would excessively choke even a mild 351.
Use of either of the other choices would depend on the performance level
of the engine. As I targeted low and mid range torque, my low cost combination
does just fine. I port matched the lower to the heads, and both the lower
and upper to the plenum gasket. The lower was close, the upper I had
to port out as much as about 1/16” in some spots. That was easily
done with a sanding roll and drill motor. I transitioned the ports up
about 1” into the runner. I didn’t use any plenum spacers
as there was no under hood room to spare at all. I just went to the local
building supply for the long center bolts that hold the plenum to the
lower intake. I used cadmium plated (bright, shiny) so they wouldn’t
rust and looked much like the stainless bolts I got for the rest of the
exterior of the engine.
For hood clearance, I had to cut away a lot of the thick underhood insulation
mostly in the center of the hood, as well as snipping out or pounding
in some portions of the underhood bracing over the intake, throttle body/EGR
plate, and the AC. Not very neat or professional, but I had a very limited
time to get the car running.
I found a used set of shorty 351 swap headers that were ceramic coated.
I decided on shorties strictly because I didn’t have the time to
modify the front of the H-pipe to use long tubes. I figured I gave up
maybe 10 or so hp and torque, but as this isn’t a radical engine,
it was worth the reduced effort and cost. However, the headers were JBA
brand and there were definitely some problems with them. I had to grind
out quite a bit of excessive weld where the tubes were welded to the
port flange plates as the weld intruded into the tube and would have
caused turbulence and restricted flow. By far the worst problem was the
fact that the collectors didn’t at all fit the front of the H pipe.
They were in the right location, they were just angled wrong.
I luckily have a wire feed welder with which I was able to reweld the
H-pipe flanges after cutting them off and reattaching them at a different
angle using some wedge shaped inserts to fill in the gaps. I like the
ceramic coating to prevent rust and reduce underhood heat, but I would
not recommend the JBA brand! It was a very difficult, time consuming,
and frustrating modification job that shouldn’t have been necessary.
The tube that goes by the steering shaft had a factory indent in it,
but it was insufficient clearance on the Lincoln. I don’t know
if it would have cleared on a Mustang. I massaged it inward a little
bit more, but it still rubbed lightly when I got the header on. The header
bolts toward the rear were difficult to access even though I used bolts
with smaller than normal heads, so I didn’t want to go through
removing the header to work the tube more, plus I didn’t want to
dent the tube in more and further restrict the flow. It was much quicker
and easier to get Mustang poly offset rack bushings. Instead of positioning
the offset to raise the rack, I set the offset to move the rack toward
the driver side (about 1/8”) which moved the rack and therefore
the shaft just enough to clear the tube. The only little problem was
that the steering wheel was then off center just a little, which I corrected
by adjusting both tie rods. This then required an alignment. I had to
jack the motor up so I could get the rack off of the mounting bolts to
install the back half of the bushings. I discovered that also made the
power steering hose connections on the rack MUCH easier to access. I
also discovered the rack just cleared the pan, and I could not have used
the offset bushings to raise the rack to correct bumpsteer as is the
normal use for them. That probably was the result of using the lower
Mark VII / Mustang vert motor mounts.
I was pleasantly surprised when I found that the large Lincoln brake
and ABS assembly did not interfere with anything. In fact, I was able
to mount the headers on both sides rather easily even with everything
underhood in place. It was just the bolts that were hard to get at toward
the rear of both headers. On the passenger side, I simply had to move
the air pump hose hanger on the inner fender strut tower upwards a few
inches to hold those hoses up and away from the headers.
To fit the air injection tube to the back of the heads, I had to cut
the tube in the straight section behind the intake and use a 6” length
of ¾” high temp silicone heater hose to widen it. The tube interfered
with the AC drier bracket by just about ½” where it goes around
the back of the passenger side head. Being in a hurry and with my AC
not working anyway, I simply removed the drier and the tubes and hoses
and the condenser in front of the radiator. The bracket or the tube will
have to be slightly modified to be able to remount the drier and reinstall
everything.
I had converted the car from speed density to mass air before I did the
engine swap to make sure the system worked and to minimize the number
of possible problem sources in case it didn’t. I got a cheap cold
air intake setup off eBay.
I put all new sensors on the engine as all my original ones had high
miles. For the intake air temp sensor, I drilled a hole in the metal
intake tube in the curve just ahead of the throttle body and used a simple
rubber grommet in the hole that fit tightly around the sensor. I extended
the wires from the stock position in the manifold base at the front of
the driver side. That got the sensor away from the exhaust gas stream
let into the intake by the EGR and the resultant sticky carbon buildup
which can’t do it any good.
The 302 fuel rails were adequate for my horsepower level and did fit
that manifold complete with the pressure regulator. I understand they
flow enough to support upwards of a high 300 horsepower range. They did
have to be widened to fit the wider 351. I cut the very hard plastic
crossover hoses off of the front and rear and used longer sections of
efi specific high pressure fuel hose. It’s also important to use
efi specific fuel hose clamps with rolled edges to avoid cutting into
the hose. NAPA and I’m sure other places have them.
I also had to modify the hard heater transfer tubes that mount along
the passenger side of the intake. I cut the little bracket that holds
them together near the front and was able to install the one that hooks
to the hose from the water pump. I had to cut and extend the other one
with heater hose, and rebend some of the exiting bends to make it fit
up to the front manifold water fitting. (Why couldn’t Ford make
it simple and make the same tubes fit both 302 and 351 Windsors?!)
As the stock 351 EEC-IV distributor had a flat tappet drive gear on it,
I had to change to the Ford “yellow stripe” roller cam gear.
The gears are pressed on, and it was quite a challenge getting the old
gear off and putting the new one on. The correct height for the gear
has to be determined and the gear pressed on to that point on the shaft.
Both the gear and shaft then have to be drilled for the tiny roll pin.
I have a drill press but it was still difficult to get a good straight
hole as the gear and shaft material are quite hard and the tiny drill
bit flexes. If I had to do it again, I would take it to a good auto machine
shop. I would also look for a light truck distributor that had the tfi
module remotely mounted in a separate small plug that mounts up by the
radiator rather than on the distributor where heat can make it fail.
There’s a short wiring harness with plugs that connect the module
to the distributor that you would also need.
As 351 blocks are taller, they also need different pushrods. My heads
happened to have the stock style pedestal rocker arm setup which is much
more difficult and time consuming to properly adjust than stud style
rockers.
HERE's how I did mine.
Proper pushrod length is important to get the proper travel pattern of
the rocker tip on the valve stem. Both Crane and Comp Cams have good
instructions on their website, and can provide pushrod length checkers
that make the job much easier. I was, however, amazed to learn that Ford
actually makes pushrods for 351s with Edelbrock Performer pedestal heads!
One of these is where I found them (I think, if I remember correctly
- not easy to find):
www.buyfordmotorsport.com,
www.nthcoast.com,
www.parts123.com,
or
www.genuine-ford-parts.com,
or just Ford Racing or a Ford high performance parts dealer should be
able to find them.
I also needed a longer serpentine belt. To measure the length, I used
a dressmaker’s cloth tape measure wrapped around the pulleys in
the same manner as the belt.
I believe that covers almost every little detail. Ford being Ford, they
of course don’t make it as easy or as relatively less costly as
Chevy or Mopar to swap to a larger small block, but it can be done.
Here are links to some good references, some with part numbers etc.
- 351 Tech Articles
- V8 Rangers, 460 Mustangs, 5.0 Ranger Pictures!
The main reasons I opted to go 351 and put up with the extra expense
and difficulty was that a 351 in a Fox is more “unique” than
a 302 stroker, the block will support more power “just in case” of
future major power increases, and mostly because it can be stretched
to much larger displacement than a 302 (besides, I’m stubborn!).
In fact, all that is required for a basic 393 is a relatively inexpensive
~$250 cast crank and stock dimension 302 pistons hung on stock dimension
351 rods. That’s one of the reasons I snapped up the Lightning
shortblock as it has the stronger stock “football”
marine rods that only need basic rebuilding plus ARP rod bolts to hold
some pretty serious power. ARP main cap studs and even a main cap girdle
would be good additional insurance depending on the power level built
into the engine. For that level combo, I would look at Speed Pro hypereutectic
or forged pistons with the skirt coating which reduces piston and cylinder
wall wear especially on the thrust side, and which are relatively inexpensive
for the power they’ll hold.
Those points aside, it’s been pretty much proven that especially
a 347 or even a 331 stroker 302 built with the same heads/cam/intake
level will out accelerate a 351 mainly because of the lighter reciprocating
assembly, and that such a motor will not cost any more to build and will
be easier to accomplish than swapping in a built 351.
But I’m planning ahead to making mine a 393 with bigger heads/cam/intake
for a Factory Five cobra replica – complete with beefed 4R70W automatic
(yes!) for ease of driving in town and sneaky stoplight getaways in my
(hopefully) golden years.
For now I’ve got gobs more torque and throttle response and am
still getting 21.5 mpg at 2500 rpm / 78 mph. Life is GOOD!
Victory Hath Its Rewards! |
- macx
