[DeTomaso] Before you buy that SOHC

[burrid1 at netzero.net]

Reprint from Hot Rod News article 7 Oct 2021 Thom TaylorwriterHot Rod ArchivesphotographerMay 26, 2015Fifty years ago, it was hailed as "Ford's greatest engine." It's still referred to as the "90-day wonder," and more commonly, the "Cammer." It's the Single Overhead Cam 427 Ford, the SOHC (pronounced "sock"). Based on Ford's 427ci side-oiler block, it was intended to be Ford's two-valve, single-overhead-cam, high-rpm answer to Chrysler's 426 Hemi for NASCAR in 1964. But racing these purpose-built engines turned "stock cars" into "not-stock cars," creating a situation NASCAR moved to stop. It banned "special racing engines" with its sights on stopping both the Hemi and Cammer. Chrysler sat out the 1965 season in protest while Ford continued with its Cammer-less 427ci wedge, which it had already been using in NASCAR for a couple of years.SEE ALL 13 PHOTOSSo what is the SOHC? Essentially, it's a two-valve, single-overhead-cam conversion of Ford's 427ci FE V8. The heads were predominantly cast-iron (though later aluminum heads were available) with a roller chain cam-drive—a 6-foot-long timing chain. The choice of chaindrive over a geardrive setup decreased development time and costs, but increased timing variables from the chain's habit of stretching under load. This resulted in the need to vary the cam timing from one side of the engine to the other to take up the chain slack. With the chain rotating in one direction, the cams also rotate in the same direction, resulting in one cam rotating toward the intake follower and the other away from the follower. To fix this, each bank requires a unique camshaft, with one a mirror of the other, so opening and closing ramps are correctly located. ALL 13 PHOTOSBesides the unique upper end, the FE block got revised oiling and cross-bolted main bearing caps were added to handle the increased rpm these engines would see. The block's cam bore now accommodated an idler gear shaft that spun the distributor and oil pump.SEE ALL 13 PHOTOSThe heads featured fully machined combustion chambers. Stainless steel intake and sodium-filled exhaust valves were fitted with both inner and outer springs, and were operated by shaft-mounted roller rockers. Early prototypes had spark plugs located at the bottom of the head, which was thought to optimize spark distribution. Ford engineers found no difference between locating plugs at the top or bottom, so in later engines, they put them at the top for easy access. In stock, single-carbureted guise, the engine pumped out 616 hp at 7,000 rpm and 515 lb-ft torque at 3,800 rpm, according to Ford factory specs.Why the SOHC went Drag RacingNASCAR's engine ban left Ford in the position of having an exotic racing engine with no venue. The development and investment Ford Engine and Foundry Division had in creating the Cammer components meant the engine had to go somewhere, so with completed parts on the shelves, Ford took the Cammer drag racing. Ford provided engine deals to Pete Robinson (Atlanta), Kenz and Leslie (Colorado), Connie Kalitta (Michigan), Tom Hoover (Minnesota), and Lou Baney (California). It's nice how Ford geographically spread the SOHC love evenly across the country.SEE ALL 13 PHOTOSThis would have been a gift of the speed gods had Ford developed the engine for drag racing, but Ford tasked the drag racers themselves to weaponize the speedway engine for quarter-mile use. The only way to find out how it would do would be to run it. With his close proximity to Dearborn and reputation as one of the top drag racers, Connie Kalitta became the first to try and sort out the mystery that was the SOHC. Connecting-rod problems dogged development from the start. But Ford's hunch about Kalitta might have been right, as he became the first person to hit 200 mph at an AHRA national event in 1965.Ed Pink was tasked with sorting out the Baney dragster, which Tom McEwen piloted initially, then Don Prudhomme. Pink told us the problem with the Cammer was not the chain—a problem he fixed with chromoly links—it was with the block. "[This engine] was meant to handle maybe 750 hp, and we were getting 2,500 hp out of it," Pink says. "We would be lucky to get four runs for qualifying and four for eliminations from a block. If we did, the crank would be laying in the bottom of a broken-up block."Obviously, starting with an existing block cut development time by plenty, but the block was never developed further for drag racing once the decision was made to go in that direction. Says Pink, "If someone would have developed a stronger aftermarket block, the history of Top Fuel racing might have been different."SEE ALL 13 PHOTOSBut Pink's chrome-moly chains didn't completely solve timing-chain woes. The chain was another concession to time and cost—being cheaper and taking less time to engineer than a geardrive setup. At higher rpm they would stretch, changing the timing a few degrees from one bank to the other. "The problem was that the driven cam was way ahead of the lagging cam," Pink says. "One tooth on the gear was about 13 degrees. The way we ran the engine, there was about a 7-degree split between the two cams." He would adjust each cam with different-size bushings that fit into the cam gear's mounting holes.As it was, the bottom end was the real problem throughout the Cammer's short four-year drag-racing career. Pete Robinson complained of oiling problems causing him to replace mains and rods after every pass. He spent months trying to extend and perfect increased oiling, discovering that adapting the 426 Hemi oiling system to the Cammer, including the Hemi's main bearings, helped engine longevity.Ford's Total Performance racing arm got involved in building a number of A/FX Factory Experimental race cars under Dick Brannan. Twelve Mustangs were created by Dearborn Steel Tubing (DST) and Holman and Moody in Long Beach, California. The first recipients were Bill Lawton, Gas Rhonda, and Phil Bonner. By the beginning of 1966, Bill Lawton had won both the AHRA and NHRA Winternationals events. Gerry Schwartz, Tommy Grove, and later Mickey Thompson were all on the Ford SOHC dole.Ford's Mercury division also fielded SOHC A/FX cars under Mercury's Fran Hernandez, awarding Don Nicholson, Jack Chrisman, Pete Gate, Fast Eddie Schartman, and Arnie "Farmer" Beswick SOHC engines for their factory-backed Comets in those first couple of years when Funny Car evolution was moving fast.SEE ALL 13 PHOTOSThen came 1966. With the Mercurys becoming true Funny Car floppers in the hyper-evolving A/FX and Funny Car categories, they would win 86 percent of the races they entered, with Dyno Don coming away with a 130-10 record, with elapsed times in the 8.10- to 8.20-second range.Ford pulled its sponsorship money out after the 1966 season to concentrate its engineering and financial interests for the upcoming Cobra Jet Mustang onslaught for 1968. Curiously, to maintain the momentum from Ford's heightened presence in drag racing, it created an off-the-books, one-off, streamlined dragster called the Super Mustang as a stopgap marketing tool for that off year. Originally a Ford Design Center exercise as a "dragster of the future," Logghe Stamping was contracted to create a chassis, and Connie Kalitta was tasked with building the injected SOHC engine. As it progressed, the project was passed on to Special Vehicles, where Brannan hitched up with Chuck Foulger, Ford Drag Team manager, to make it work. After initial Kalitta shakedown runs, Tom McEwen was given the driving chores, and what a chore it was.In retrospect, the combination of a short wheelbase, sprung rearend—when all Top Fuel dragsters were solid mount—and the extra body weight resulted in times more than a second and 40 mph off of average fueler times. After a few appearances, it was unceremoniously parked, surviving today as a curiosity.SEE ALL 13 PHOTOSBack to reality, the SOHC arsenal continued to make a name for itself. "Sneaky Pete" Robinson took the 1966 NHRA World Championship in his Cammer-powered dragster. Dyno Don Nicholson had a winning season with his Cyclone Comet, which continued into the 1967 season, with A/FX evolution segueing from the use of original bodies to tube chassis with fiberglass lift-off bodies. Logghe Stamping in nearby Fraser, Michigan, became the source of ladder-type tubular chassis for the SOHC-powered cars.In 1967 Kalitta came out of nowhere to win the NHRA Winternationals, the AHRA Winternationals the next week, and finally the NASCAR winter championships in Deland, Florida. Running a 6.81-second at 219-mph quarter-mile, he would stick with the SOHC from 1966 to 1970.Prudhomme drove the Baney dragster for two years, snagging the first 6-second NHRA national event winner honors with it. Other SOHC dragsters hot on the trail were Jim Cooke's driven by Bob Muravez, aka Floyd Lippencott Jr.; Tom Hoover's short-tail/long-tail; and later Chuck Griffith. Danny Ongais won almost every event he entered in 1969 with Mickey Thompson's SOHC Mustang Funny Car, and "Dyno Don" Nicholson took the 1971 Winternationals with a Cammer-powered Maverick in the new no-handicap Pro Stock class.SEE ALL 13 PHOTOSBut the end of the Cammer was drawing near. As supplies, funding, and interest from Ford waned, all at about the same time, most of the Cammers were replaced with the now tried-and-true 426ci Chrysler Hemis. One holdout was Pete Robinson. Known for his experiments in weight reduction, early electronics, and aerodynamics, he felt that the overhead-cam configuration was better suited for nitro drag racing than Chrysler's Hemi, and he continued experimenting with it and racing it. ALL 13 PHOTOS SEE ALL 13 PHOTOSBy then, Top Fuel times were getting quicker running Chrysler's Elephant motors, and on the horizon was Art Donovan's 417ci Hemi in 1972, Keith Black's 426-based Hemi, and John Rodeck's aluminum big-block Chevy-based engine in 1974. And, of course, Ford had a new hemi head adapted to another of its production blocks by then. There was a new boss in town, the Boss 429, based on the 460ci production block. Ford was all in with the new 429, willing to abandon what it knew for what the company hoped would be. Unfortunately, the 429 would prove to be vastly inferior to the legend it replaced.NASCAR Did Not Ban the SOHC in the EndNASCAR did finally say "yes" to the Cammer. The initial ban on "special racing engines" on October 19, 1964, wasn't the end of Ford's attempts to twist NASCAR's arm to accept the Cammer. Ford continued to lobby NASCAR to allow the Cammer for the 1966 season, but in December 1965, NASCAR banned it once again. Then in April 1966 NASCAR reversed its decision, with some caveats. The engine could only be used in fullsize Galaxies and was limited to a single small, four-barrel carburetor. But the killer was the weight handicap the SOHC Fords would have to carry over the Dodge and Plymouth Hemis: 430 pounds! With that, the Cammer was to become a drag-racing-only effort.SEE ALL 13 PHOTOSHot Rod's 427 Cammer BuildHot Rod did an extensive article on building a repro 427ci SOHC back in 2009, and there are lots of good tips and info. You can find it by Google searching "Hot Rod SOHC Build 2009."New Cammers You Can BuyThe supply and cost of original 427 Cammers makes them almost unobtainable, but that never stopped hot rodders. Two manufacturers are making Cammer heads and assorted components, and one of them is even manufacturing an aluminum or iron FE block—take your pick.Robert Pond Motorsports (RobertPondMotorsports.com) has aluminum and iron FE reproduction blocks that are exactly like the 427ci FE blocks but have no lifter provision, as they were not needed with the overhead-cam arrangement. The company also manufactures dual-plane intakes, aluminum heads, and front timing covers.Bill Coons ran a 1957 Thunderbird for years with a Cammer and reproduces aluminum SOHC heads, front timing covers, backing plates, and more. Various builders are using his heads, but Coons currently has no website, so check with your local Ford FE engine builder—we're sure they have more info. 
-------------- next part --------------
   Reprint from Hot Rod News article 7 Oct 2021


   [1]Thom Taylorwriter[2]Hot Rod Archivesphotographer

   May 26, 2015

   Fifty years ago, it was hailed as "Ford's greatest engine." It's still
   referred to as the "90-day wonder," and more commonly, the "Cammer."
   It's the Single Overhead Cam 427 Ford, the SOHC (pronounced "sock").
   Based on Ford's 427ci side-oiler block, it was intended to be Ford's
   two-valve, single-overhead-cam, high-rpm answer to Chrysler's 426 Hemi
   for NASCAR in 1964. But racing these purpose-built engines turned
   "stock cars" into "not-stock cars," creating a situation NASCAR moved
   to stop. It banned "special racing engines" with its sights on stopping
   both the Hemi and Cammer. Chrysler sat out the 1965 season in protest
   while Ford continued with its Cammer-less 427ci wedge, which it had
   already been using in NASCAR for a couple of years.SEE ALL 13 PHOTOS

   So what is the SOHC? Essentially, it's a two-valve, single-overhead-cam
   conversion of Ford's 427ci FE V8. The heads were predominantly
   cast-iron (though later aluminum heads were available) with a roller
   chain cam-drive--a 6-foot-long timing chain. The choice of chaindrive
   over a geardrive setup decreased development time and costs, but
   increased timing variables from the chain's habit of stretching under
   load. This resulted in the need to vary the cam timing from one side of
   the engine to the other to take up the chain slack. With the chain
   rotating in one direction, the cams also rotate in the same direction,
   resulting in one cam rotating toward the intake follower and the other
   away from the follower. To fix this, each bank requires a unique
   camshaft, with one a mirror of the other, so opening and closing ramps
   are correctly located. ALL 13 PHOTOS

   Besides the unique upper end, the FE block got revised oiling and
   cross-bolted main bearing caps were added to handle the increased rpm
   these engines would see. The block's cam bore now accommodated an idler
   gear shaft that spun the distributor and oil pump.SEE ALL 13 PHOTOS

   The heads featured fully machined combustion chambers. Stainless steel
   intake and sodium-filled exhaust valves were fitted with both inner and
   outer springs, and were operated by shaft-mounted roller rockers. Early
   prototypes had spark plugs located at the bottom of the head, which was
   thought to optimize spark distribution. Ford engineers found no
   difference between locating plugs at the top or bottom, so in later
   engines, they put them at the top for easy access. In stock,
   single-carbureted guise, the engine pumped out 616 hp at 7,000 rpm and
   515 lb-ft torque at 3,800 rpm, according to Ford factory specs.

   Why the SOHC went Drag Racing

   NASCAR's engine ban left Ford in the position of having an exotic
   racing engine with no venue. The development and investment Ford Engine
   and Foundry Division had in creating the Cammer components meant the
   engine had to go somewhere, so with completed parts on the shelves,
   Ford took the Cammer drag racing. Ford provided engine deals to Pete
   Robinson (Atlanta), Kenz and Leslie (Colorado), Connie Kalitta
   (Michigan), Tom Hoover (Minnesota), and Lou Baney (California). It's
   nice how Ford geographically spread the SOHC love evenly across the
   country.SEE ALL 13 PHOTOS

   This would have been a gift of the speed gods had Ford developed the
   engine for drag racing, but Ford tasked the drag racers themselves to
   weaponize the speedway engine for quarter-mile use. The only way to
   find out how it would do would be to run it. With his close proximity
   to Dearborn and reputation as one of the top drag racers, Connie
   Kalitta became the first to try and sort out the mystery that was the
   SOHC. Connecting-rod problems dogged development from the start. But
   Ford's hunch about Kalitta might have been right, as he became the
   first person to hit 200 mph at an AHRA national event in 1965.

   Ed Pink was tasked with sorting out the Baney dragster, which Tom
   McEwen piloted initially, then Don Prudhomme. Pink told us the problem
   with the Cammer was not the chain--a problem he fixed with chromoly
   links--it was with the block. "[This engine] was meant to handle maybe
   750 hp, and we were getting 2,500 hp out of it," Pink says. "We would
   be lucky to get four runs for qualifying and four for eliminations from
   a block. If we did, the crank would be laying in the bottom of a
   broken-up block."

   Obviously, starting with an existing block cut development time by
   plenty, but the block was never developed further for drag racing once
   the decision was made to go in that direction. Says Pink, "If someone
   would have developed a stronger aftermarket block, the history of Top
   Fuel racing might have been different."SEE ALL 13 PHOTOS

   But Pink's chrome-moly chains didn't completely solve timing-chain
   woes. The chain was another concession to time and cost--being cheaper
   and taking less time to engineer than a geardrive setup. At higher rpm
   they would stretch, changing the timing a few degrees from one bank to
   the other. "The problem was that the driven cam was way ahead of the
   lagging cam," Pink says. "One tooth on the gear was about 13 degrees.
   The way we ran the engine, there was about a 7-degree split between the
   two cams." He would adjust each cam with different-size bushings that
   fit into the cam gear's mounting holes.

   As it was, the bottom end was the real problem throughout the Cammer's
   short four-year drag-racing career. Pete Robinson complained of oiling
   problems causing him to replace mains and rods after every pass. He
   spent months trying to extend and perfect increased oiling, discovering
   that adapting the 426 Hemi oiling system to the Cammer, including the
   Hemi's main bearings, helped engine longevity.

   Ford's Total Performance racing arm got involved in building a number
   of A/FX Factory Experimental race cars under Dick Brannan. Twelve
   Mustangs were created by Dearborn Steel Tubing (DST) and Holman and
   Moody in Long Beach, California. The first recipients were Bill Lawton,
   Gas Rhonda, and Phil Bonner. By the beginning of 1966, Bill Lawton had
   won both the AHRA and NHRA Winternationals events. Gerry Schwartz,
   Tommy Grove, and later Mickey Thompson were all on the Ford SOHC dole.

   Ford's Mercury division also fielded SOHC A/FX cars under Mercury's
   Fran Hernandez, awarding Don Nicholson, Jack Chrisman, Pete Gate, Fast
   Eddie Schartman, and Arnie "Farmer" Beswick SOHC engines for their
   factory-backed Comets in those first couple of years when Funny Car
   evolution was moving fast.SEE ALL 13 PHOTOS

   Then came 1966. With the Mercurys becoming true Funny Car floppers in
   the hyper-evolving A/FX and Funny Car categories, they would win 86
   percent of the races they entered, with Dyno Don coming away with a
   130-10 record, with elapsed times in the 8.10- to 8.20-second range.

   Ford pulled its sponsorship money out after the 1966 season to
   concentrate its engineering and financial interests for the upcoming
   Cobra Jet Mustang onslaught for 1968. Curiously, to maintain the
   momentum from Ford's heightened presence in drag racing, it created an
   off-the-books, one-off, streamlined dragster called the Super Mustang
   as a stopgap marketing tool for that off year. Originally a Ford Design
   Center exercise as a "dragster of the future," Logghe Stamping was
   contracted to create a chassis, and Connie Kalitta was tasked with
   building the injected SOHC engine. As it progressed, the project was
   passed on to Special Vehicles, where Brannan hitched up with Chuck
   Foulger, Ford Drag Team manager, to make it work. After initial Kalitta
   shakedown runs, Tom McEwen was given the driving chores, and what a
   chore it was.

   In retrospect, the combination of a short wheelbase, sprung
   rearend--when all Top Fuel dragsters were solid mount--and the extra
   body weight resulted in times more than a second and 40 mph off of
   average fueler times. After a few appearances, it was unceremoniously
   parked, surviving today as a curiosity.SEE ALL 13 PHOTOS

   Back to reality, the SOHC arsenal continued to make a name for itself.
   "Sneaky Pete" Robinson took the 1966 NHRA World Championship in his
   Cammer-powered dragster. Dyno Don Nicholson had a winning season with
   his Cyclone Comet, which continued into the 1967 season, with A/FX
   evolution segueing from the use of original bodies to tube chassis with
   fiberglass lift-off bodies. Logghe Stamping in nearby Fraser, Michigan,
   became the source of ladder-type tubular chassis for the SOHC-powered
   cars.

   In 1967 Kalitta came out of nowhere to win the NHRA Winternationals,
   the AHRA Winternationals the next week, and finally the NASCAR winter
   championships in Deland, Florida. Running a 6.81-second at 219-mph
   quarter-mile, he would stick with the SOHC from 1966 to 1970.

   Prudhomme drove the Baney dragster for two years, snagging the first
   6-second NHRA national event winner honors with it. Other SOHC
   dragsters hot on the trail were Jim Cooke's driven by Bob Muravez, aka
   Floyd Lippencott Jr.; Tom Hoover's short-tail/long-tail; and later
   Chuck Griffith. Danny Ongais won almost every event he entered in 1969
   with Mickey Thompson's SOHC Mustang Funny Car, and "Dyno Don" Nicholson
   took the 1971 Winternationals with a Cammer-powered Maverick in the new
   no-handicap Pro Stock class.

   SEE ALL 13 PHOTOS

   But the end of the Cammer was drawing near. As supplies, funding, and
   interest from Ford waned, all at about the same time, most of the
   Cammers were replaced with the now tried-and-true 426ci Chrysler Hemis.
   One holdout was Pete Robinson. Known for his experiments in weight
   reduction, early electronics, and aerodynamics, he felt that the
   overhead-cam configuration was better suited for nitro drag racing than
   Chrysler's Hemi, and he continued experimenting with it and racing it.
   ALL 13 PHOTOS


   SEE ALL 13 PHOTOS

   By then, Top Fuel times were getting quicker running Chrysler's
   Elephant motors, and on the horizon was Art Donovan's 417ci Hemi in
   1972, Keith Black's 426-based Hemi, and John Rodeck's aluminum
   big-block Chevy-based engine in 1974. And, of course, Ford had a new
   hemi head adapted to another of its production blocks by then. There
   was a new boss in town, the Boss 429, based on the 460ci production
   block. Ford was all in with the new 429, willing to abandon what it
   knew for what the company hoped would be. Unfortunately, the 429 would
   prove to be vastly inferior to the legend it replaced.

   NASCAR Did Not Ban the SOHC in the End

   NASCAR did finally say "yes" to the Cammer. The initial ban on "special
   racing engines" on October 19, 1964, wasn't the end of Ford's attempts
   to twist NASCAR's arm to accept the Cammer. Ford continued to lobby
   NASCAR to allow the Cammer for the 1966 season, but in December 1965,
   NASCAR banned it once again. Then in April 1966 NASCAR reversed its
   decision, with some caveats. The engine could only be used in fullsize
   Galaxies and was limited to a single small, four-barrel carburetor. But
   the killer was the weight handicap the SOHC Fords would have to carry
   over the Dodge and Plymouth Hemis: 430 pounds! With that, the Cammer
   was to become a drag-racing-only effort.SEE ALL 13 PHOTOS

   Hot Rod's 427 Cammer Build

   Hot Rod did an extensive article on building a repro 427ci SOHC back in
   2009, and there are lots of good tips and info. You can find it by
   Google searching "Hot Rod SOHC Build 2009."

   New Cammers You Can Buy

   The supply and cost of original 427 Cammers makes them almost
   unobtainable, but that never stopped hot rodders. Two manufacturers are
   making Cammer heads and assorted components, and one of them is even
   manufacturing an aluminum or iron FE block--take your pick.

   Robert Pond Motorsports ([3]RobertPondMotorsports.com) has aluminum and
   iron FE reproduction blocks that are exactly like the 427ci FE blocks
   but have no lifter provision, as they were not needed with the
   overhead-cam arrangement. The company also manufactures dual-plane
   intakes, aluminum heads, and front timing covers.

   Bill Coons ran a 1957 Thunderbird for years with a Cammer and
   reproduces aluminum SOHC heads, front timing covers, backing plates,
   and more. Various builders are using his heads, but Coons currently has
   no website, so check with your local Ford FE engine builder--we're sure
   they have more info.

References

   1. https://www.motortrend.com/staff/thom-taylor/
   2. https://www.motortrend.com/staff/hot-rod-archives/
   3. http://www.robertpondmotorsports.com/