Thunder Lizard; The Story of My Olds 442

By Milton J. Schick

In mid-September, 1963, a few days after my 7th birthday (born 4 Sept. '46), my Dad took me to the national new car announcement showing Oldsmobile, held that year in Kansas City, Missouri.  1964 was the first year for GM's new intermediate size automobile.  When I first laid eyes on the 1964 Olds F-85 upon the theater's stage, I immediately fell in love with that particular body style.  When the 442 came out for 1964','; I had to have one.

During the Thanksgiving break in my senior year in college during the Fall of 1968, I found one.  My maternal grandmother lived in Independence.  We always had Thanksgiving evening dinner with her.  After dinner, I drove over to Ketchum Olds on 40 Highway to check the used car lot.  Sifting in the back was a black 1964 442.  It was too dark to tell anything about her.

Early on Friday morning, I called Ketchum's used car department.  They said the car had just come m on a trade and hadn't been cleaned up yet.  I asked how much they wanted "as is." The reply - $800.00.  I told them don't touch it, and I was leaving now.  I stopped by the bank and was at Ketchum 30 minutes later.  The car was a Cutlass 2-door coupe with the 442 option (police pursuit 320 hp, 330 cube engine, 4-on-the-floor, dual exhaust).  It had 113,000 miles on it.  The front end had been wiped out in the near past, because both front fenders and the hood were new.  There was a huge bondo patch in the lower right rear tender.  The interior was well used.  I loved her.

In the Spring of 1971, she first hit the streets with a new lift and 482 cubes of might.  By the Spring of 1975, with her third engine, second rear axle housing, and fourth suspension system, she was in her basic final configuration.  Only minor changes have been made since 1975.  I'll own her forever.  She will be my coffin.  The following is her vital statistics:

The first two engines were 482 cube 455's.  They didn't work.  The cylinder walls were too thin.  The third engine, built October 1974 to May 1975, is the final form and the absolute best.

BLOCK - Olds 455 bored and align honed with deck torque plate 0.060 over to 468 cubes.  Block deck trued and crank mains align bored.  Inside of block deburred and all surfaces smoothed and then painted with red electric motor internal sealer.

CRANKSHAFT - The original crank, and the crank for the first engine, was nodular cast iron.  The good crank is a forged steel 455 unit from the Olds R&D division, left over from the CroSal all-aluminum 455 road racing engine and sold to the CrankShaft Company as a core by Olds.  The crank has the Dyna-Rev two center counter weights added and is Tuffrided.

RODS - Olds rods are forged alloy steel.  The first two engines used 455 rods.  The rods in the third engine are from an Olds 425 cube engine.  425 rods (7.0" c-c length) are 0.265' longer than 455 rods (6735" c-c length).  This change brings my 468 much closer to the ideal 1.7 to 1 rod length to stroke ratio with a new ratio of 1.647 to I.  The stock 455 ratio is 1.585 to 1.  The 425 rods are deburred and the sides ground smooth.  After shotpeening, the center-to-centers were matched, rod ends resized, piston end weights matched, rod end weights matched, and bronze bushings installed in the piston ends.  The longer rods make an unbelievable difference.

PISTONS - The first two engines used Amen forged pistons that weighed 950 grams, without their full length 0.980" pin.  For the third engine, the forged pistons are from Brooks Racing Components and weigh only 660 grams with pin.   The tapered pin is only 3" long at 0.927" diameter (same pin as a small block Chevy from BRC).  Rings are Sealed Power double moly, 1/16" top and second compression and 1/8" oil.  The compression ratio is exactly 11 to 1 with a totally smooth flat top polished surface.  There are no valve reliefs.  None are needed.

HEADS - The heads are the same with all three engines.  These were the first Olds heads ever modified by Air Flow Research.  Several spare test heads at AFR had to be R&Ded before my heads were touched.  These heads do not follow conventional Olds wisdom.  Small block Chevy 2.02" stainless steel intake valves (Manley) and 1.75" stainless steel exhaust valves (Ansen) are used, with hard chromed stems.  The valves are very highly polished.  The Olds "C" head intake passage flowed more than enough air for a 2.02" valve, but it has trouble getting it out, particularly when a 1.75" valve is installed.  Regardless, AFR determined larger exhaust valves were really the way to go.

The exact same situation was experienced with my first high-performance engine I built when I was 16 (in 1962).  This engine was a 394 Olds.  I left the stock 1.875" intakes alone and jumped the exhaust from 1.625" to 1.75", the largest valve that could be fitted.  It worked like gangbusters! The 455 2nd generation Olds heads and engine liked the same treatment.  According to AFR, my standard 455 modified heads with 2.02" and 1.75" valves flowed 25% more air/fuel mass mixture than a similarly modified set of 442/W30 455 heads with 2.0625" and 1.625" valves.

The intake ports were purposely not exactly matched to the intake manifold.  The bottom edge and one vertical edge matches the manifold, but the top edge and the other vertical edge are slightly wider than the manifold.  In that way, when the fuel mass passes the two mismatched edges, it's like falling off a cliff.  The fuel tumbles and swirls in maximum turbulence, enhancing atomization.  From the reverse direction, the protruding edge of the intake manifold can prevent fuel reversion.  In addition, the intake passage between the smoothed port lip and the valve pocket is left rough as cast.  The rough surface should add to turbulence and fuel atomization.  The intake valve pocket and the entire exhaust passage is so highly polished it reflects.  Those areas need smooth flow.

The combustion chamber is also highly polished.  The chamber volumes have been matched to 70 cc.  The round smooth chamber shape now looked almost like a Chrysler poly-sphere.  The smooth tops of the pistons are also highly polished.  There are no sharp points in the entire combustion area.  Piston deck height is 0.100".  I know, not much quench.  The engine does not appear to need it or want it.  At 11 to 1 compression and 360 total timing at 4000 rpm (120 initial), the engine can run on 92 octane unleaded.  Racing fuel is mixed with the unleaded at a 4 to I ratio mainly to get the lead for valve lubrication.  Of coarse, the compression ratio can and will put the extra octane to good use.

One minor point.  Most people will tell one to remove the small hump inside the exhaust passages in an Olds head when porting.  The small hump is a boss for threaded-in air pump fittings for a California smog engine.  AFR said don't do it.  Without the small humps, the air flow falls on its face.  With the small humps, the air flow goes in the right direction and accelerates toward the center of the exhaust port to interface precisely with the opening to the header tube.

The rocker arms are Crane 1.6 to 1 needle bearing forged aluminum for 7/16" screw-in studs for a small block Chevy.  Pushrod guide plates were from a ram-air Pontiac, until Mondello came out with a set for the Olds.  Pushrods are from Smith Brothers.  Valve guides use phosphor bronze spiral inserts.  Valve seals are 289 Ford rubber umbrella seals.  Valve covers are Mickey Thompson.

CAMSHAFT - The cam used in all three engines is a hydraulic grind from Crower Timing specs are as follows, but was before the 0.050" lift convention:
   Intake open @ 36°; @ 0.040 lift = 10°
   Exhaust close @ 36°; @ 0.040 lift = 10°
   Intake close @ 68°; @ 0.040 lift 42°
   Exhaust open @ 84°; @ 0.040 lift ,58°
   Intake/Exhaust overlap = 72°; @ 0.040 lift 20°
   Intake duration 284°; @ 0.040" lift = 232°
   Exhaust duration 300°; @ 0.040" = 248°
   Intake and Exhaust valve total lift 0.495"

Heavy single springs and anti-pump-up lifters are also Crower.  Valve oil seals are 289 Ford.  They fit inside the spring damper without interference and allow just enough oil for proper lubrication.  By the dyno and observed actual use on the street, recommended engine redline appears to be 6800 rpm.  However, valve float doesn't occur until 8300 rpm.

Idle rpm in neutral is 1100.  Idle rpm drops to 900 in gear.  The idle is a little lopey but smooth.  There are no problems with the idle in street driving.

CAM/CRANK TIMING - The first two engines used a double roller timing chain.  For the third engine, cam/crank timing is handled by a Pete Jackson double idler gear drive made exclusively for Mondello to market.

IGNITION - From 1971 to 1993, the ignition was a Ronco Vertex magneto.  In 1993, the mag was pulled and a MSD 7AL-2 ignition unit with Blaster 2 coil was installed.  An Olds point distributer was sent to Stinger Electronic Ignitions and converted into an electronic trigger unit with a total mechanical advance of 28° @ 4000 rpm.  With 8° added to the crank (set at 12° initial @ 1000 rpm), total timing is 36° @ 4000 rpm.  A MSD wide cap assembly is used on the distributor for the ignition wires.

OIL SYSTEM - A stock Olds Toronado oil pump is used with a Milodon extended pickup, attached to the bottom of the oil pump.  Oil pressure runs between 40 and 55 pounds.  Add-on top-end oil restrictors are not used, as is the case with some racers.  The Olds engine does not have an oil problem.  The oil pan has an extended sump, increasing oil capacity to 7 quarts.  A 442 W-30 windage tray is attached to the main caps to control oil slosh.  An external engine oil cooler is used. *SEE NOTE BELOW.

INTAKE SYSTEM - The intake is an Offenhauser 3600 Equa-Flow single quad high rise manifold.  In my past experience, an Offy 360 manifold always seemed to work better throughout an Olds engine's power range than any Edelbrock manifold.  I know this sounds politically incorrect, but that is my experience.  The carb is an 850 cfm Holley double pumper with front and rear jets increased 0.010".  Two Carter high performance 72 gph electric pumps are mounted at the gas tank.  Each pump, with its own separate 3/8" fuel line, feeds one bowl of the Holley carb.

EXHAUST SYSTEM - Headers are by ED.  Each tube is 1 3/4" o.d. by 36" long, with a 3" collector by 18" long.  Exhaust and tail pipe are 2 1/2".  Mufflers are 2 1/2" inlet and outlet turbo mufflers.  A tailpipe exits in front of each rear wheel, with the outlet pointed at the tire tread, 10" away.

DYNO RESULTS - The third engine was pulled and put on a dyno after it bad accumulated 1000 miles.  It produced 573 HP at 6300 rpm with the Ronco Vertex magneto.  Torque is 600 foot pounds at 4000 rpm and the curve is very flat.  Torque effects are attributed to the long rod setup with the ultra-light weight pistons.  However, when the mag was pulled and the MSD system installed in 1993, the magneto's parasitic drag was eliminated.  The mag produced 100,000 volts, but fired only once.  The MSD 7AL-2 makes only 55,000 volts, but fires it several thousand times over 20 degrees of crank rotation.  Thus, the MSD system produces a much longer duration spark with a total electrical energy many times that of a magneto, producing a flame that should consume every speck of fuel mixture.  The HP could now very easily be around 600, also.

TRANSMISSION - The transmission has always been a B&M unblown competition, manual shift only Turbo 400, with an 11" fully furnace brazed torque converter with needle bearings.  The trans has an aluminum deep pan and a separate external oil cooler.

REAR AXLE - At first, she used a 1959 Olds rear axle with a Detroit Locker and 3:90 gears.  However, the left wheel bearing failed at 2000 miles.  At 5500 miles, coinciding with the beginning of the build of engine number three, the bearing was dead again.  It was discovered the left side of the housing had warped when the suspension brackets, which were removed from the original 10 bolt axle housing, were welded onto the '59 axle housing.  There was only one logical cure.  A brand new Chevelle 12 bolt housing was purchased.  The housing ends were cut off and housing ends from another '59 Olds housing were welded on.  That was necessary for mounting the rear disc brakes.  At the same time, the housing overall length was shortened 1/2" on each side to allow the rear wheels and tires to finally fit under the rear fenders.  The inside sidewall of the rear tires clear the outside of the frame by 1/2~~, the closest point.  I had absolutely no desire of tubbing the floor pan for the rear tires.

The rear axles are Street capable (circle track/road racing rated) from Summers Brothers.  Another Detroit Locker is used for the differential, holding 4:10 gears.

TIRES & WHEELS - Current tires are BFG 11R4 Comp T/A radials, rated temperature A and traction A.  The fronts are P225/70R15 (27.0" diameter).  The rears are P275/60R15 (27.5" diameter).  The Mud & Snow tread will handle submersion in water, for her safety.  The extreme cornering ability of the Comp T/As is also for her safety.

The wheels are Cragar Screamers, 15x7 front and 15x8.5 rear.  This wheel was only made between Spring 1973 and Fall 1974.  It looks like a dull polished Ansen Sprint but with a sloping outward cone center.

BRAKES - Hurst/Airheart 1 75x2-06 Formula 1 type dual spot disc brakes on each wheel.  The dual 1" piston master cylinder is manual.  Braking action allows the tires to just come to the point before brake lockup, utilizing the maximum traction capability of the rubber compound.  The tires just barely pull through the brakes on high speed solid stops, preserving maximum controllability of the suspension.  Braking deceleration is rapid and firm.

SUSPENSION - Steering is manual.  She is set up more like a road racer than anything else.  (I can't put her on the dragstrip, because I refuse to ruin the interior with a rollbar.) The first three suspension arrangements tried during the first 5500 miles of her life were not satisfactory.  Coinciding with the third engine building and the replacement of the rear axle, the fourth suspension system was installed.  26 years and 14,000 miles later, the system components were replaced due to age.  The basic system still works and will now work better.

Starting in October 2000, all OEM rubber bushings were replaced with black polyurethane bushings.  The front 1965 F-85 air conditioning springs # 5272 were replaced with new springs of the same type (333 lbs. per inch).  The rear 1964 to 1966 Chevelle station wagon springs # 5235 were replaced with new springs of the same type (143 lbs. per inch).  The front Gabriel Strider shocks and the rear Gabriel Adjustable E shocks (both set on extra-firm) were replaced by Edelbrock IAS shocks.  The rear Lakewood lower control arms and boxed original upper control arms were replaced by a full set of very heavy duty control arms with black polyurethane bushings and side braces from Edelbrock.  The front 442 1 1/8" sway bar was replaced by a 1 5/16" sway bar from Helwig.  The 442 7/8" rear sway bar was replaced by a 1 1/8" sway bar from Performance Suspension.  Cornering performance is only limited by the traction of the tires.

BODY - Her body is dechromed and painted with white IMRON.  The front wheel openings are radiused in the front for tire clearance.  The top of the rear wheel openings were raised 3" for additional vertical tire clearance in 1972.  The front inner fender panels were removed.  There is no heater system, and the firewall is clean.  The stock dash was completely removed and replaced with a clear anodized 1/8" thick aluminum panel, which carries all the switches and Stewart Warner gauges.  Almost all of the original wiring was removed and replaced with only what was needed.  The arm rests are removed.  Interior floor pan sound deadening is completely removed.  The rear seat is removed, and the package area is completely cut out.  The Ford truck diesel battery is located in the trunk.  Any item that is not needed has been removed.  The interior has a black headliner, black vinyl rolled and pleated seats and door panels, and a black carpet.  A black cushion fits into the rear seat/package area space and isolates the trunk noise from the passenger compartment.  She weighs 3200 pounds with a full tank of gas and no one in it.

FUTURE MODIFICATIONS - When the current brake pucks wear down, instead of rebuilding the disc brakes, the dual spot calipers will be replaced with a set of Hurst/Airheart 1 75x2-QC quick change calipers.  The two brake pads for each of these new calipers have double the surface area of the four pucks in each double spot caliper.

The Offy single quad intake will be pulled and replaced with an Offy 360° Equa-Flow high rise dual quad manifold using a 2" Offy carb spacer under each Carter 750 cfm AFB.  An oval 10" x 21" by 3" high aluminum air cleaner will be built for the new system.  This induction system will look and run better for an early '70s street machine.  A true dinosaur when compared to some of the current hardware.  With the change in induction, could the HP climb toward 650?

The hood will be retired and replaced with a lift off carbon/epoxy composite hood.  A central air scoop will cover the new air cleaner as it sticks through the hood.

As I said before, Thunder Lizard will live as long as I do.  And, as a tribute to the thunder lizards of 60 to 100 million years ago, She is one of the very last of her breed, a fire breathing street machine from the golden age of factory produced muscle cars.

p.s. One could title this piece "A Rocket Scientist's Rocket."

* NOTE: The major complaint is the Olds oil system pumps too much oil up to the top, and it doesn't return fast enough.  For stock engines, the factory really doesn't care, as long as production goes out the door with next to zero warranty claims.  Its easy to hog out and smooth and polish the oil return holes at both ends of the heads.  However, don't forget to make sure the area underneath the oil return holes in the upper block is also opened up and smoothed out.  The opening in the valley over the cam must be opened up and have all the casting flash ground away, along with any defects or flaws in the valley sides and floor that could impede oil flow.  Since the intake manifold heat passages in my heads are permanently blocked and my intake runs cold, I leave the baffle over the lifters out, so that it can't interfere with any oil return.  Then, a sanding wheel needs to be run over the entire surface of the valley to smooth it out.  The final procedure is to paint the inside top surface of the heads and the entire inside surface of the block with red electric motor sealer.  The final slick, smooth surface, with the hogged out oil return passages in the head and upper block, will make sure the oil will get back to the pan as soon as possible.  (Obviously, the entire inside of the block has been deburred.)

The crank must be cross drilled everywhere and have all the oil holes deeply chamfered, just like anyone would do on any high-performance or racing engine.

When I built my engines, Milodon did not yet make deep oil pans for an Olds.  My oil system starts out with a stock oil pan with the bottom of the sump cut off.  I then cut the entire sump off of a Toronado pan.  The Toronado sump is rotated 90 degrees with the drain hole to the rear and then welded onto the stock sump.  The result is a 7 quart oil pan.  I use a Toronado oil pump with a Milodon oil pickup.  (At least Milodon had a really trick bottom sucking pickup.) A rectangular hole matching the oil hole in the Milodon gray anodized aluminum pickup is cut into the case hardened steel of the oil pump bottom plate.  An aluminum block about 3" long acts as an extension between the oil pump bottom plate and the Milodon pickup.  The oil goes into the pickup and is sucked directly into the bottom of the oil pump gears.  The oil pump gears continue to run directly on the stock case hardened steel bottom plate, preventing wear.  A 442 W30 windage tray completes the oil pan/pump setup.

At idle on a warm engine, I have 25 to 30 lbs. pressure, depending on temperature.  Street cruise is 40 lbs.  Maximum pressure is 55 lbs., where the relief opens.  Oil is Kendal GT-1 40 weight.  Rod bearing clearance is 0.0025" and main bearing clearance is 0.0035."

I've never restricted oil flow internally.  However, on the first 455, I followed some advice that said to plug the oil squirter on the galley plug behind the timing chain.  Wrong.  When I lost the crank in the first engine and pulled it down (only 5000 miles), I found the Cloyes double roller timing chain was worn out.  It didn't get enough oil.  That's the last time I did that.  I never, ever desired to restrict oil flow anywhere else.

Now don't go off the deep end and say, "Ha, he lost his crank because of oil." That's not what happened to the nodular cast iron crank.  My 455 was bored to 482.  The Ansen 11 to 1 pistons weighed 990 grams without the massive pins.  I had already found out the Crower cam was good to 8300 where the valves floated.  The problem is, I didn't know my horsepower peak was around 6300, and I was constantly over-revving.  I usually shifted the B&M unblown comp TH400 at 7000 to 7500.  It was way too much.  Unknown to me, the nodular cast iron crank couldn't take it, and the heavy reciprocating assembly was causing it to flex in the center.  When the crank went, it beat out number 3 main to 1/16" clearance, spun mains 2 and 4, and mains 1 and 5 were so perfect, they looked like they bad just come out of the box.  All the rod bearings were okay, except there was babbitt material embedded in them.  The time was late summer, 1973.

After an extensive search, I found a forged steel crank and had CrankShaft Company add 2 center counter weights to it.  I now had the advantage of heavy momentum for increased torque generation and a super rigid crank Godzilla couldn't break.   Unfortunately, the oil consumption at wide open throttle that plagued the first engine was still with the second 482.  The cause was the 0.125" overbore.  The cylinder walls were walking at high RPM and letting the oil ring float.  After 500 miles, I pulled the engine out again.

The third and final engine is a 468.  The 0.060" overbore is max, as far as I am concerned.  However, this engine uses 0.265" longer 425 rods and BRC pistons that only weight 660 grams with the pin.  This long rod engine with the light reciprocating assembly runs rings around the first 2 engines and then runs off and hides.  This one was dynoed.  That's why I know max horse is at 6300 (about 600 HP).  This engine has only 14,000 miles on it since the spring of 1975.  A few years ago, I looked inside.  It looked like I had just built it.

Of coarse, it uses the oil system that I described above.  There's more than one way to make it work, and work reliably, with max power and efficiency.

OIL SEALS - Umbrella rubber valve seals attach tightly to the valve stem and ride up and down with the stem.  Small block Chevy c-ring oil seals are installed in a groove at the tip of the stem and only keep oil from running down the valve stem from the top of the valve spring retainer.  The seal's umbrella is intended to prevent excessive oil splash from flooding the valve stem horizontally and running down the guide into the intake/exhaust passage area.  When the valve is wide open, the umbrella rests on top of the guide and blocks oil access to the top of the valve guide.  Remember, the clearance is very slight, the exhaust guide is somewhat pressurized, and the intake side has a slight vacuum draw at low rpm and higher draw at high rpm.  Olds V8s always sucked a larger amount of oil around the valve stems because of the stupid hard plastic valve seals Olds insisted on using.  The plastic seals never fit tight on the valve stem and couldn't control oil flow very well.

When phosphor-bronze guides were first used on race engines, the builders installed Perfect Circle all Teflon seals as usual.  This seal clamped tightly around the machined top of the valve guide and scraped oil off the valve stem while it went up and down.  (The top of the guide was machined to accept them.  The outside diameter of the seal was the same as that of the guide, or smaller.) They seemed to be okay on stock cast iron valve guides, however, after a few years, it was finally noticed the Teflon seal's attachment system cut too much oil away from the phosphor-bronze guides.  (How often does one check the valve stem clearance on a race engine? The circle burners found it first.) Phosphor-bronze needs a small amount of oil present for proper lubrication and extreme long life.  There was one prominent instance of where the phosphor-bronze guides with P.C. all Teflon seals were worn out after less than 5000 miles on a street driven high performance engine.  Perfect Circle Corp. didn't want to know about the claim and denied it because it was a "modified" engine.  The mods didn't repeal the laws of physics or violate the principles of engineering.

For an Olds engine, it was discovered that 289 Ford rubber valve seals fit perfectly on heavy single springs with damper and worked extremely well.  With the 289 seals, the phosphor-bronze guides received adequate oiling, and no sign of oil from the valve guides would show up in the engine.  On some applications, the 289 seals had a small enough outside diameter of the umbrella to clear the inner spring on a dual valve spring setup.

The P.C. all Teflon seal was extremely small in diameter and would fit inside triple valve spring systems.  There was another P.C. seal made from rubber that still clamped on the top of the valve guide (with a much bigger outside diameter) but had a Teflon ring insert that sealed the valve stem.  It was not uncommon to have the Teflon insert pop out of the rubber, making the seal useless.  Many people simply used the OEM rubber seals and didn't worry about it, as long as the OEM valve seal would clear the inside of the spring setup they were using.  In hindsight, they were probably right.  However, the plastic Olds valve seals have always been next to useless.  The use of the 289 seal was a great idea and solved the valve guide oil consumption problem in any Olds second generation V8.

LONG RODS - Long rods increase piston dwell time at top dead center for both holding compression longer and exhausting all of the burnt gases during full exhausting.  The piston on a long rod rises slower during the last half of travel upward and drops slower during the first half of downward travel than a piston on a shorter rod.  However, the piston on the long rod speeds up and travels faster than the piston on the shorter rod as it nears bottom dead center, stops at BDC, and as it speeds away from BDC.  The increased speed with the long rods toward BDC creates a higher order vacuum and packs the cylinder tighter with air/fuel mix, increasing volumetric efficiency.

Note what the long rod engine testing said about smaller valves, breathing ability, and cast iron head configurations (from a 2 part article in Circle Track Magazine in 1989).  Also remember, the testing was done with a Chevy 320 using, I believe, 2.02" intakes and 1.625" exhaust valves.  My 468 has 148 more cubes being fed by 2.02" intake and 1.75" exhaust valves.  The testing said an engine with small valves will breathe better with long rods.  Logic says my 468 would pull better numbers in improvement with the 148 extra cubes and almost the same size valves.  The dyno results for my 468 confirmed it.  I'm sure AFR could tailor a set of heads to optimize the effects on horsepower and torque generation from the long rods.  Too bad I didn't think about the long rod setup for the first engine, when I had AFR build my heads originally.  Who knows, maybe the AFR heads are working that way, anyway.

HEADS - At the 1969 Specialty Equipment Manufacturer's Association (SEMA) show in Las Vegas, Mondello met their Waterloo.  Air Flow Research (AFR) set up a complete engine dynamometer in their large booth.  Remember, AFR invented the flow bench for accurately porting engine heads.  First, they installed a full house, normally aspirated 327 Chevy with top-of-the-line Mondello ported heads.  AFR ran the engine and pulled the best power figures.  Then, they removed the heads and installed a set of AFR modified heads.  The improvement? Would you believe an increase of 55 HP and 50 pounds of torque over the Mondelloes? Mondello was livid, but there was nothing they could do about it.  One can make all the suppositions and wild guesses on how heads work all they want, but in the light of solid engineering design, the bullshit dissolves.  Unfortunately, from what I've seen and heard, Mondello has never changed.

Head Porting - As of 1 January, Air Flow Research discontinued doing custom head work.  AFR now only does their own line of head and engine components for, as usual, Chevies and Fords.  However, Dan at AFR did confirm that what AFR did to my heads in 1970 was absolutely correct.  He didn't think much of Mondello.  He suggested I contact Chapman Racing Heads in Salt Lake City, Utah.  Chapman then referred me to Marty at Kroyer Racing Engines in Las Vegas, Nevada, 702-651-2071.  Marty is an Olds nut, like us.  Olds is what he drives for fun and for racing, professionally.  I wound up telling him about my 468, and he agreed with everything, including that Mondello is only after the buck and will tell one anything they want to hear.  He thought the 425 7.0" long rods were a great idea, because he had done the same thing in the past.  Also, the necessity for leaving the AIR nodule in the exhaust was very valid for directing the exhaust flow to the center of the exhaust port and avoiding port wall boundary layer interference.  That's part and parcel to working fluid aerodynamic theory in a duct.  Mondello is doing everyone a great disservice in telling everyone to wholesale grind out the AIR nodules from the exhaust port.  Olds engineers weren't stupid.  They weren't going to do something to hurt performance, when the emission mandates were already affecting performance.  Think about it.

If the AIR nodules really hurt performance, then Olds would have removed them from the heads on all W-30 options.  They didn't.  Anyway, when you're ready, Marty is willing to build your cast iron heads, even though he usually works only on aluminum heads.  The cost will be about $1500.00, plus your parts.  I know, expensive.  By the way, Marty had very interesting things to say about Edelbrock aluminum heads.  A good set of flowed and ported Edelbrock aluminum heads will NOT produce any more power than a good set of flowed and ported "C" iron heads and could even produce less power than the iron heads.  The iron heads are better and have the advantage of keeping the combustion chamber hotter.  Wouldn't that statement cause a mass rebellion on the Olds list and at 442.com! Anyway, SI recommended that I also contact Richard at Westcoast Cylinder Head Service, 818-705-5454, and see what he could do for Olds heads.  As I write this letter, I have a call into him, but I haven't heard anything yet.

ENGINE HISTORY AND CFM DEMANDS The first engine, a 482, used dual 1000 CFM Carter Thermoquads, with the same 11-1 CR, the same Air Flow Research heads, and the same Crower cam.  This engine would rev to 8300 RPM, the valve float limit.  I normally shifted at 7500.  Unbeknownst to me, my nodular iron crank was screaming in pain.  At 5000 miles, exactly, I had flexed the crank in the center too much and, one night, spun main bearing 2 and 4, beat the clearance out to about 0.060" on number 3 main, the thrust main, and mains 1 and 5 looked like I had just installed them.  The rod bearings also looked new.  So much for oil restrictors, for I've never used them and don't believe in them, and oil is not the problem in an Olds.  It's the damned nodular iron crank with a heavy reciprocating assembly, even though I was revving the engine way too tight.  I should have been shifting at 6500.

For the second engine, I found an Olds forged steel 455 crank, via a tip from Dave Smith at the Olds R&D engine lab, at the CrankShaft Company.  I had CrankShaft do their Dyna-Rev conversion, which adds 2 center counterweights to the crank, for a total of 8 counterweights.  The heavy crank gives the same affect as a 40 or 60 pound flywheel, instant torque dump off the line, due to the massive momentum buildup.  This steel crank went in the old 482 block, but a few friends talked me into using only a single Holley 4781 instead of the dual Thermoquads.  The power improvement with the crank actually offset the deletion of the dual quads, but I seemed to have lost some top-end revving ability.  However, 6500 RPM shifts were no problem.  Unfortunately, this engine only went for 500 miles, for my oil burning problem was still with me.  The 482 block had been sonic checked, and the walls seemed to be plenty thick.  However, what threw me was the affects of the thin-wall casting techniques on the rest of the block.  Apparently, the 0.125" overbore caused the cylinder walls to walk at high RPM, aided and abetted by the affects of the thin-walled casting in the webbing throughout the block, and the oil rings would lose stabilization and flutter at high RPM.  There was no cure for it.

So, I pulled the second engine apart and built a third and, by a lightyear, the best engine.  I finally got it right.  The third engine still used the forged steel crank, the same Crower cam (but a new one, for the Hell of it), the same Holley 4781 and Offy 360 high rise manifold, the same Ronco Vertex magneto, and the same AFR heads.  However, the 482 block was replaced with a 468, the 455 6.735" rods were replaced with 425 7.0" long rods, the 990 gram (without pin) Ansen 11-1 pistons were replaced with ultra-lightweight BRC 11-1 pistons at 660 grams (including the pin), a Pete Jackson gear drive was added, and the 2" Hookers were junked and replaced with 1.75" x 36 long Headers-By-Ed.

I had to know if this engine worked, so, after it was first started and broken in as installed in Thunder Lizard, the 468 was then pulled and placed on an engine dyno with the Headers-By-Ed.  Best power reading was 573 HP at 6300 RPM and 600 pounds of torque at 4000 RPM, using the Ronco Vertex magneto which had been used in the first 2 engines.  The MSD 7AL-2 system I use now seems to produce better seat-of-the-pants acceleration and top end power.  Maybe she's now at 600 HP.  Who knows?

However, the main thing is what the dyno said about the top end pull, which was confirmed by feel, after I had enough experience with this engine in Thunder Lizard.  The dyno indicated the engine was beginning to run out of air at above 5500.  Part of the reason was the indicated volumetric efficiency of 116%.  I didn't appear to have near enough CFM for the demands of the engine.  Longer rods contribute to both increased torque and top end breathing ability.  The AFR modified heads are specifically setup to breathe at top end and to rapidly evacuate the exhaust.  In the car, I can feel her straining to go higher in RPM, quicker.

I've felt this before.  My Chrysler 331(348) early hemi (in my '23 "T" roadster) was originally built with a Wieand very low profile dual quad manifold and two 750 CFM AFBs.  The cam was a Crower flat tappet with 300 degrees duration and 0.540" lift at the valve.  CR was 11.5 to 1.  This engine should have screamed, but at 5500, the engine literally shut itself off.  As long as I shifted at 5500 in each gear of the B&M Torkflyte, everything was fine.  By shear luck, I found a used Rotoflize tunnel ram blower manifold.  This manifold design really didn't work, for a ram manifold for a blower was somewhat redundant.  The blower rams in and compacts air for the engine, anyway.  I cut the blower mounting plate down on the sides and built dual 3 inch high plenums for the front 4 and rear 4 cylinders.  Again, the two 750 AFBs went on top.

Guess what happened? The first time I took the roadster out, I very rapidly zoomed the hemi up to 8000 RPM in first and second before I shifted.  The low profile Wieand dual quad manifold was cutting off air flow to the hemi.  The engine couldn't get the air it needed, quick enough.  The exact same thing is happening to Thunder Lizard and her 468.  The 850 Holley won't let enough air in.  I've been living with it since 1975.

For various reasons, some of which I'll readily admit are stupid, I've refused to do anything about it.  10 years ago, I bought 2 Edelbrock 750 AFBs and an Offy dual quad high rise manifold for her.  About 3 years later, I figured out I needed to put 2 Offy 2" aluminum spacers under the AFBs to pick up a little ram affect that I'm convinced she needs.  However, I've now gotten somewhat organized.  A close friend of mine will cut the dual quad manifold to fit my heads (AFR cut 0.080" off during the modifications) and build a custom aluminum billet oval air cleaner, using a 3" tall Ford 427 type air filter, for her new look.  I'll build the CFRP carbon/epoxy lightweight hood, with a 4" high air scoop (placed properly, aerodynamically) for her.  If I'm lucky, I may get this all done by September.

I'll accomplish several things.  First, her top end breathing problem will be solved, the way I should have done it 25 years ago.  (She's still an adolescent.  Her 468 is only 14,800 miles old.) Second, I've always run dual AFBs on all my high performance vehicles.  They've always worked perfectly and trouble free.  It's about time she got hers.  (The 4781 has screwed up more times than I can count.) Finally, in her role as the dinosaur of the Golden Age of Street Machines, Thunder Lizard will now have the dual AFBs to match her image.


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