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October 3, 2000
Just purchased a 74 Pantera- The car is perfectly stock. The only problem I'm
having is the water temperature gauge works on and off while driving. Do
the 74's need additional cooling updates? On very hot days, after driving, I
will park the car and hear fluid purculating out of the overflow bottles. I
check the levels, and don't think I'm losing that much coolant.

The 74 Pantera has no special cooling problems. But a 'perfectly stock'
Pantera has a multitude of small glitches. First, the radiator cap: using a
US cap on the Italian tank usually results in leaks, since the tank neck is
slightly too deep and usually rough. This means that hot water from the
engine expands past the cap into the overflow tank. After cooling, instead of
sucking the water back into the engine, the sloppy cap sucks air instead.
After a couple of cycles of this, the water level is really low and the
engine overheats. The fix is to remove the tank and have a radiator shop
desolder the neck and add a US neck. Add in a new cap, be sure the connecting
hose between the surge and overflow tanks is crack-free and this part should
work fine.
Second, if most of your driving is in traffic, or a fast highway run
followed by traffic, the stock radiator fans will not keep the engine cool;
they are physically too small. What is needed is a pair of fans that deliver
a 20mph air blast, or about 900 cubic feet per minute (cfm) each. Stock fans
deliver 300 cfm. Vendors have a variety of replacements
Third, once air has gotten into a Pantera cooling system, it is difficult to
get it all out. Air gathers in the radiator tanks and forces water to bypass
around it, cutting cooling capacity. To bleed air, first jack up the right
rear as high as you can get it and remove the radiator cap. Then crack the
bleeder screw on the front left side and listen for air hissing out. When you
get only water, close the screw and try the other side bleeder. Keep track of
the water level during this time- don't let the level drop too low or you'll
have to start over. Top off the tank, tighten the cap, lower the car and
start the engine. After a minute or so, crack the left bleeder screw again
and listen for more air. This sequence may need repeating for several days
before the air is gone for good.
There are other, less likely scenarios that result in your machine
overheating, but these are the main ones.
As for your intermittent temp gauge, it may be the wire to the sending unit
is loose, or a bad sender. The sender is a stock Mustang part costing only a
few dollars. Incidentally, the sender should NOT be in the surge tank as it
is stock. If for any reason, the water level drops, the sender will read the
air temperature in the tank, not the engine water temperature. There is a
pipe plug in the front of the block, just below the thermostat housing.
Remove the plug and add the sender- this is the way Ford built millions of
Mustangs etc. The plug you removed fits in the hole in the tank for a no-cost
change. Now you will read a constant water temperature of the cooling system.
Good luck- J. DeRyke

Sept. 21, 2000 Hello Boss,
I've been road racing my (dare I mention it) Mustang for several years.
It's a Boss 351, and is really fun. Yes, I have a Pantera on my list, but
it will have to wait a few more years. Any way, I'm hoping you might be
more in touch with my engine demands. I try to keep the engine close to
stock for reliability. It basically has only a cam, carb and headers, and
runs 11.5 compression on race gas. This is a small budget operation.
Unfortunately, I've had 2 recent rod bearing failures. Both of these
engines were "balanced" and "blueprinted" short blocks, built by the best
Ford machine shop in town. They also both had the main oil restrictor kit
I run Mobil 1, have an external oil line from the front of the block running
to the rear oil port. I've also installed the Moroso high pressure oil pump
spring in a stock volume Melling oil pump. The oil pan is an 8 QT Canton
road race pan with trap doors, and I run a Canton Accumulator. It has a
Modine water/oil cooler ot the filter, and a Ron Davis heat exchanger
radiator with built in oil cooler. The engine dynoed 337 at the rear wheels
at 6100 rpm, with a stock single plane manifold and Holley 750. I plan on
rebuilding the engines myself from now on at yearly intervals. This should
be less than 50 hours of engine time as I only make it to 6 events a year,
and limited street driving.
How exactly does the restrictor kit work, and should I be utilizing it on a
road race set up? Also, are there any real advantages to running the
"racing" type Clevite or Federal-Mogul main and rod bearings.
Thanks much for helping out a cousin.
Daniel R. Haynes, Capt, USAF
96 FTS Reserve Instructor Pilot

Dear Daniel,
As to your first question: First guess: be very sure the engine is using the "football-head" connecting rod bolts for real Boss 351C rods. The squarish std head bolts WILL stretch &
fail under racing stress. It may be necessary to go to aftermarket connecting
rods for your race setup. Quite a few 351C racers have lost stock rods for
one reason or another and finally went to Carillos cut for SB Chev rod size
which cured the problem of rod big-end distortion (for about $1000 plus crank
machining & rebalancing).

2. How exactly does the restrictor kit work, and should I be utilizing it on a
road race set up?

Sure- the 5 primary oil restrictors reduce oil flow up to all the cam
bearings, and the secondary one restricts flow to the left-side lifter
galley. Presumably, this largely reduces oil pressure losses at the crank,
but there is no easy way to restrict the right side lifters since they are
oiled from the main oil galley. It gives plenty of oil for solid lifters but
too little for hydraulic lifters.

3. Are there any real advantages to running the "racing" type Clevite or
Federal-Mogul main and rod bearings?

No; they are made of harder babbit than street bearings so they are
physically stronger but much more intolerant of dirt so you tend to score
cranks. You aren't losing bearings as I understand it, you are losing the
concentricity of the rod big-end, possibly to detonation at top rpms. The rod
bore distorts from the high-rpm hammering causing the ends of the bearings to
bend inward, forming an oil scraper that strips oil from the journal. After
milliseconds this way, the bearing overheats, melts and spins, & the game is
over. Check fuel pressure at your upper rpms; its pretty common to find
top-end lean-out, detonation and subsequent rod failure. My opinion is you've
got plenty of oil and good parts but are losing rods for one or more of the
above reasons - Hope you get your dream car someday! J. DeRyke

Sept. 21, 2000 I recently purchased a 72 Pantera GT5 upgraded. It has 48,000 miles and on
the 800 mile trip home I started to get a noise from rear end area. It is a
whop whop type noise that sounds rotational as slowing down, then as
approaching the stop it changes to a rotational scrape. Kind of like a wheel
weight touching caliper. I raised the rear end in the air and inspected all areas
for loosness, scrape marks and u-joint cap movement.Nothing obvious. I suspect
bearings. My exhaust is so loud I can't run it and hear anything under the car.
Maybe remove half-shafts and spin tires while using stethescope. What do you
think and is this something you have experienced before?
Thanks for your time

Diagnosing a noise is difficult enough when you're in the car; but, by long
distance, its a real challenge. OK; in my experience, rear wheel bearings
seldom fail. What often fails is the outboard stub-axle shaft, due to
too-loose clearances to the bearings causing the softer axle to wear, then
wobble. You may be hearing wheel studs or the rear brake disc rubbing because
of a worn, wobbly stub axle. To check this, remove the luggage tub. Then
while you watch the rear axle VERY closely, have someone of substantial size
throw a hip into the rear fender (but not enough to dent it!) If the axle is
worn or you have a bad bearing, the axle and half-shaft will move upward
noticably as the force is applied. A perfect axle setup will not move upward
at all. Also, check how tight your wheel studs are. The inside end of the
wheel studs only clears the outboard upright retainer by 0.050", so any
looseness, or a bent retainer plate or perhaps one of the Phillips screws
that hold it, will result in a scraping noise. This may only happen under a
load, which will make finding it on a lift very difficult. Please let us know if this solves the problem or not. Good luck- J DeRyke

Sept. 21, 2000 Dear Boss, Are there any instructions out there on how to lower the floor pans? (Name witheld)

Not that I know of. There was a photo-story in the POCA news some years ago that recorded this change. The job isn't too difficult, and Hall even sells a cheap kit to do this. Without the kit, the floor below the seat pan is cut at the sides and at the rear firewall, bent down and filler pieces of sheet are welded at both sides and the back. The cuts are at the edge of the console and along the inner edge of the rocker panel, up to the front floor cross-member. Most guys do NOT cut the cross-member. The drop is at max 2", since you don't want the seat base to be the lowest spot on the car! Cut this way, the job is easier and floor stiffness is retained, but adjustability goes away since the seat will no longer slide back & forth in its new 'pocket'. And because adjustability is gone, you can discard the adjustment rails and gain another inch or so of headroom. I don't know what effect cutting the floor cross-member has on body rigidity, but cutting it would allow one to retain
the seat rails. We have one guy 6'4" & 220lbs who says he now is comfortable driving his dropped- floor Pantera. Remember, you probably only need alter the drivers side. Good luck- J DeRyke

Sept. 21, 2000 Hi, have have long wanted to put a centrifugal superchager (Paxton) on my
Pantera but it won't fit behind the fire wall on pulleys. I have recently
heard of an amazing idea to run a pulley down under the engine to a
rod. then have the rod run under the engine till it meets a pulley
behind the engine where the pulley goes up. Up there you mount a
supercharger off that pulley. (remote mounted supercharger)
I think it would work. how about you? Have you ever heard of this?
does a company sell it?

P.S. I recently did some research on superchargers and found a way
around retarding the timing and compression of my engine. ATI Procharger
D-1 Supercharger w/intercooler included. The intercooler works wonders
and are more efficient than Paxton or Vortech. And no I don't want a
Roots Eaton supercharger. Procharger D-1 has 26 psi of boost The D-3m has
36 psi of boost.,
Can make for a fun time with out need to retard.
Gary Travinski

Indeed. What you describe is similar to what DeTomaso used to drive the A/C compressor and alternator for the Mangusta, and what Wilkinson used to drive a twin-Roots Magnacharger on the Pantera. Wilkinson's shaft doesn't go under the engine (interferes with removing the oil pan etc) but under the left cylinder head, close to the block. The Mangusta setup puts the driveshaft on bosses on the intake manifold, protruding out the back of the engine. Be careful in rigging a Paxton- the direction of rotation of the puffer is important. Wilkinson may have some parts around for a drive setup; call him. Good luck- J DeRyke

Sept. 21, 2000 - Is there any reason why the Pantera AC radiator cannot be converted to an oil
cooler? I would like to begin taking my car to the track, but have high
speed heating concerns. Tom Kuester

Nope. Matter of fact, this has been done successfully since at least 1980.
Only potential concern is, airflow thru the AC condenser depends on a swirl
from the rear deck down and back into the AC grille, then down onto the
ground; the fan is a sucker type. As speeds go up, the swirl is further out
behind the car, and somewhere around 130 mph, it will be so far back that the
AC condenser will be in a slight vacuum. This may be why AC hoses blow from
overpressure/inadequate cooling at very high sustained speeds. So as long as
you keep track of this little glitch, it'll work OK as a oil cooler, at very
low cost, I believe. I do suggest an oil thermostat or cut-off valve to keep
from overcooling the oil at low speeds around town. Cheers- J DeRyke

Sept. 21, 2000 I bought a 72 pre-L model less than a week ago. I am new dealing with
Pantera's. My car is on the verge of overheating all the time. The fluid
level is full and all three fans are working. I have heard of "fixes"
for this in articles but nothing specific is mentioned. I read your
response to the guy who travels at 130+ mph .I just want to drive in
traffic without worrying. Is this the same "fix" for me? Thanks Mike McMillan

Dear Mike,
1)- We've seen a recent rash of water temp sending-unit failures. Try removing & testing it with a pan of hot water & glass thermometer, replacing if req'd.
2)- Where is the sender? stock was in the remote water tank; should be shifted to the block, horizontally under the thermostat.
3)- How's the thermostat? Mine only last 1 yr before going bad. Under the thermostat is a lg brass washer with a hole in the center. If that's gone, 25% of the water will never see the radiator. If it's there and you don't care about warm-up time being a little longer, drop a 3/8" freeze plug into the brass washer hole. This will drop the hot water temp 10-15 degrees. If you do this freeze plug thing, any Ford thermostat will work. If not, you MUST use a 351C-specific thermostat, which is a 191 degree unit.
4)- Bleeding air from the cooling system is tedious but necessary. Key is having the rear of the car as high on a jack as you can get it, and bleeding repeatedly for 2 or 3 days.
5)- What's "verge of overheating"? '71-72 Panteras came with a 0-220 gauge, replaced with a 0-260 in '73-'92. 215 is not considered 'hot' anymore. My wife's '97 Z-28 constantly runs 215-220 and is not "hot" by the gauge until it reaches 245!
6)- A US radiator cap won't seal properly on a stock surge tank. The tank neck is too deep for US caps (Euro caps are slightly longer)so water is heat-displaced. Then on cooling, air is sucked in instead of water being pulled back. The next time you start the car, you're low on water with no leaks! In addition, the seal base in the tank is rough so the cap won't seal. Fix: take the tank to a shop, cut the neck off and resolder a US neck.
7)- Using stock fans? Pusher-fans are less efficient at cooling @ low speeds. Sucker-fans with a shroud are much better in traffic. You need a 25 mph breeze thru the entire radiator, not just the 10" circles in front of the blades.
There are a few less-likely things, but try ALL of these first & let me know how it works.
Good luck- J DeRyke

Sept. 21, 2000 - Hello .... where can I go on the internet to get a simple explanation
(with graphics) on what a 4 bolt main is ? thanks for your help ...
Chuck Friday

Four-bolt mains refer to engine blocks that have main bearing caps with four retaining bolts in each. The main caps retain the crankshaft and its bearings so they absorb lots of force and impact, and the two extra bolts tend to keep the main caps (and hence the crankshaft and its bearings) from shifting around fractionally. The two big bolts closer to the center are quite long and in fact are all that are used on '2-bolt main' 351Cs used in non-performance applications. The smaller side bolts require special main bearing caps with 4 bolt holes, and if you have an extra set around, they can be added to a 2-bolt block by simply drilling & tapping the extra 10 holes (2 for each of the 5 main bearings). Incidentaly, on a 351C, due to the extreme thinness of the block, the extra strength added by the extra bolts probably does very little towards durability; the main caps may be more firmly held, but the block flexes in other areas regardless. This is not true for Chevy blocks. The r!
ule for 351-Cs is, if you got 'em, use 'em; if not, don't worry-you won't miss 'em. Cheers- J DeRyke

Sept. 21, 2000 Dear Boss,
I have a 72L. The tire on the left side is far closer to the front
inner fender than the tire on the right side. In fact, when I turn to
the right the left side tire rubs on the inner fender. Can this be
adjusted. I have replaced the A arms on the left...but it only added 1/2
inch or so of clearence.

Dear Richard, Welcome to the wonderful world of semi-hand-built Italian cars, Richard! The body jigs used by Vignale to hold parts for welding Panteras together must have been a little off, because your complaint is common. Don't waste time & money replacing parts; instead, mark the interfering areas with chalk, remove the tire and get out your "adjuster"- a large hammer! Seriously, this is the accepted way of adding a little clearance for larger tires. Stock OEM front tires were 185-70x 15 on 7" wheels, and there was plenty of clearance. Now, with 245-50x 15, -16 and -17s available, there is interference. In front, I run 245-50x 15s on std 8" (rear) Campy's, and not only is there interference where you note, almost all on the left side, but also with the cowl drain pipe at the back of the wheel well and with the inner rear panel. All of these areas yielded to a little hammering and a fresh coat of paint. Note also that removing the front spring spacers will make the rubbing worse, even though their removal is desirable from a handling & appearance standpoint. 10 minutes of pounding should take care of the rubbing. Good luck- J DeRyke

Sept. 21, 2000 Dear Boss Wrench, I have a 1971 pantera and have an electrical problem I hope you can help with. The tail lights & brake lights work fine until you turn on the running
lights or headlights. Then ,the brake lights no longer work and both lights
blink when either turn signal is used. The front turn signals work
correctly.The car was recently painted, but none of the wiring was changed.
I think I have checked all of the grounds, but I' m not totally sure I know
where they all are. Any help would be GREATLY appreciated. (Name witheld)

BINGO! What you have is typical of a bad ground and nearly identical to what
got me on the way home from a recent Pantera meeting. There are two separate
grounds you need to check. The first is at each tail light on the inside of
the rear trunk. The second is the central ground under the dashboard, above
and behind the tach. This stud has a whole bunch of grounds that probably
need to be removed, wire brushed and reassembled & tightened. The good news
is, its a no-cost fix. Bad news- it will take you an hour or so depending on
how flexible your spine is. good luck- J. DeRyke

Aug. 12, 2000 I have a Pantera purchasing question. I see that the '71 models have a high compression ratio- 11:1 vs other model years having a lower compression ratio. The '71 model owner's manual states 98-100 octane required. Do '71 owners have to search out gas stations having high octane or do they buy octane boosters? This would make long trips a challenge. Do '71 owners lower the compression in their engines to use pump 92 octane gas?
Gerald Galbreath

Gerald, after 29 years with the worlds most-modified sports car, I doubt if ANY are still as-built. No, 11:1 c.r won't work on today's 'gas'. Most guys that run that much compression either run race gas (readily available @ $5 a gallon) or they back off the timing, add thicker head gaskets and/or a radical cam which itself reduces the compression pressure. But as I said, most have been modified for a more reasonable 9:1 c.r.(iron heads- if its got aluminum heads, you can get away with 10:1 or a little more). Start the engine- if it doesn't instantly rattle itself to death, someone's been in there to fix it. If it pings and rattles, you are looking at some amount of expense, and there are other, more drivable Panteras available. My 2 cents- J DeRyke

The fuel gauge sender unit in my '72 pre-L is shot. Can I assume it isn't the original setup because the fuel line is separate from the sender unit? Can this unit be replaced with an affordable universal sender, or can this one be rebuilt? BTW it has the original Veglia gauge. If you can share some info on these questions or the current requirements of the Veglia gauge I would be most grateful.
Bob R

Early cars like yours and mine had separate gas-out pipes from the later
integrated units. This is stock. I wrote an article in a recent PI on adding
a second outlet to a Pantera gas tank that shows all this. But briefly,
remove the engine screen and upper tank cover. This exposes the tank with the
sender. To remove the sender, you must remove the rear quarter window. This
is easy- it's held in by friction only! Slide a screwdriver between the
chrome trim and body and carefully lever the whole thing out without cracking
paint on the edges. Now, remove the screws holding the sending unit and
maneuver the long float arm out through the window opening. Once out, the actual
sender can be seen. I think a similar unit from a '71-72 Alfa Spyder will
adapt in; I checked electrical resistances and the two units were very close.
Or, new stock assemblies are over $200, so.... good luck- J DeRyke

I have a pantera GTS 1989 and the oil temp gauage climbs rapidly to about
130C degrees when I increase speed to about 130 mph plus. This happens pretty quickly (In about 10 minutes), but if the car is ideling the temperature stays down at about 90 degrees C.

I live in a pretty hot climate where temperatures during the day get up to 45
Degrees C. It is worrying as it is close to the limit of the guage which is
145 Degrees C. Is this normal.? I am worried about blowing something out.
If it is not normal what could be wrong and what can I do about it. John B. (Emirates)

Yes. Happens to us all above about 130mph. The oil temp and your water temp
will track each other within a few degrees under normal conditions. 130mph+
is not normal. The Silver State runners that average 150mph+ for 90 miles
actually drive with the oil temp as a speed indicator. Regular oil chemically
breaks down above 280F, and synthetic oil is good to around 300F. Above that,
oil ceases to be a lubricant- and BOOM! So they limit their speeds to keep oil
temp within a "safe zone". To do this regularly, you need an oil cooler; the
bigger the better. The best one currently on the market is a Fluidyne
water-to-oil cooler. It plumbs into your car's radiator lines and can be
mounted any place you find convenient, like alongside the transaxle.
According to one GT-5 owner, it reduced his oil temp @ 150mph by over 30
degrees F while only raising the water temp by 5-7 degrees F. They have a
U.S. website ( Needless to say, you need a really GOOD
brass water radiator, thicker than the stock unit, to make it work well. If
you decide to stick an air-to-oil cooler in your car, the only place it fits
is in front of the right rear tire, with a louvered splash panel to protect
it from debris. Porsche mounts two pretty big air-to-oil coolers in front of
the front wheels, with ram air intakes. On a Pantera, you'd have to cut the
body. Get the biggest air-to-oil cooler you can find- it probably won't be as
good as a Fluidyne, but smaller air-to-oil coolers are a complete waste of
money. Let me know how it all turns out and good luck- J DeRyke
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