An Entertaining & Informative Vintage Automobile Internet Magazine

Part I: Bending the rules in 1960s NASCAR Grand National and 1970s NHRA Championship Racing

By David Greenlees: In upper echelons of auto racing the pressure to win races and championships is intense. Automakers, team owners, chief mechanics, and engineers sometimes bend the rules in a calculated risk to gain an advantage over their competitors to win, and afterward, hope that they can get away with it without being caught.

We will be sharing with you photos of exotic and extremely expensive engine components used in NHRA Championship Drag Racing Series in the 1970s, and NASCAR Grand National Series competition in the 1960s. The individuals involved in the use of this equipment won national championships and the cheating was never detected because post-race engine inspection in both sanctioning bodies only covered the carburetors, intake manifold, cylinder heads and the measurement of the bore and stroke of the cylinders. 

In this case in the 1960s and 70s the cheating involved the use of roller bearing engine lower ends in engines where the crankshaft, connecting rods and camshaft all spun in anti-friction roller bearings, instead of conventional plain bearings.

This crankshaft is a one piece and is heat treated and surface hardened. The connecting rods and bearing races are split in the middle. The bearing retainers are also split in half and assembled around the crankshaft, and split races are in the block and main bearing caps. The roller bearings run directly on the hardened crankshaft.

  • Top to bottom – Custom Mark IV 427 c.i. Chevrolet V-8 crankshaft forged of aircraft quality alloy steel. Center – Main and cam bearings, races, and thrust bearings. Bottom – Connecting rods machined from forged aircraft alloy steel with internal bearing races. Photo dated April 6, 1972.

Freed of friction caused by the parasitic drag of the oil (shear) between crank and camshafts and conventional plain bearings the lower end of an engine rotates quite a bit easier on roller bearings. In addition a smaller oil pump can be used because this type of a bearing can survive on a fraction of the amount of the oil pressure necessary with plain bearings. The power consumed in overcoming this friction and loss due to a larger oil pump can then be used to propel a racing car to higher speeds than competitors engines using conventional bearings are capable of and this advantage can and was used to win races.

We have decided to not name names and companies involved with making this equipment and the individuals using this equipment out of respect to their surviving family members and because of possible litigation.

Because of the decision before anyone starts crying foul and says this is a hoax or the photos were doctored in photoshop, rest assured that what you see in the small period photos (2″x 3″,) which are in our own collection is real. The only thing that has been removed from the photos we are sharing with you is the logo of the engineering company that masterminded these conversions.

Also in our possession is a custom made forged V-8 crankshaft (one of three made and the only one that survived,) a set of main and connecting rod roller bearings, and one connecting rod that was used in a 427 c.i. Ford engine in the 1960s in Nascar Grand National Series competition that resulted in winning the championship laurels.

We will return in the near future with Part II of this story and a photo of another even more remarkable 427 Chevrolet V-8 lower end roller bearing conversion and more details of the construction details on both conversions.

41 responses to “Part I: Bending the rules in 1960s NASCAR Grand National and 1970s NHRA Championship Racing

  1. Then engineering company shouldn’t be shy. It was 47 years ago and they are under no obligation to spill the beans of who this stuff was made for. Even it they did, the person or organization that bought the parts didn’t have to use them in a competition where they weren’t allowed.

    But, I guess not everyone wants to be Smokey Yunick. He basked in this kind of stuff.

    • The Engineering Company does not exist anymore. I have met one of the owners of the Company who has since passed away and learned a lot from him. I was very fortunate to inherit his automotive engineering library.

      • I can see your dilemma. There are enough clues here to parse out the most likely entity, and naming names would not really accomplish anything.

        The NASCAR champions were great drivers, no matter the car prep (the old joke at the track was it was easier for a good driver to win with a bad car, than it was for a bad driver to win with a good car), and since certain parts were always checked and certain parts were never checked, who’s to say whether there was an advantage? The other racers may have been doing the exact same things, for all we know, putting the competition back to square one.

  2. Had a ’52 Porsche 356 with a Hirth roller-bearing crank. The rods were one-piece, and the roller cages were put on the crank’s rod journals before the crank was bolted together. The system worked pretty well, but the bearings didn’t like it when the engine was “lugged.” The rods here are two-piece, but how are the apparently one-piece (?) cages installed on the crank?

        • The races as I sough some are made in one piece an later they are broken in two halves throug a grinded groove across. So they are “one off”each one and are not interchangeables the halves. The roller cages are similar done. Nowadays roller cages are made from a heat resistan plastic and are open in a “C”shape.(these last are used in some gearboxes…

          • Thanks Jose, always nice to see a non-native English speaker here making an informative contribution!

  3. I worked with a fellow mechanic who built & raced cars (I forget what type/class) One of his tricks was to glue an appropriate amount of brake lathe shavings to an aluminum part. If the part was inspected, a magnet would stick to it.

  4. Sounds like the opening of Dragnet, “The story you are about to hear is true”,,,Good for them, I don’t see it as cheating, it was just a better way of doing something and the people calling cheaters are just bummed they didn’t think of it first. I saw a demonstration of an Asian motor, I think it was Honda 600 car 4 cylinder. The were demonstrating the roller bearing crank and block, no cylinders or heads, the person grabbed the crank and spun it like a sewing machine. He said, “try that with your flat bearing motors”.

  5. Sorry, cheating is cheating and lying is lying. If they were so proud of this design and such modifications were permitted, they’d have showcased it and bragged endlessly. These modifications were not legal and those were the rules that were laid down by Nascar.
    This is precisely the problem today, folks want to dismiss or diminish morally reprehensible conduct.
    I was taught differently.
    We’re losing our moral compass.

    • I agree about your “moral compass” comment.
      Why hold anyone accountable for anything?
      Anything can be excused for a variety of reasons.

      But, in my opinion, NASCAR complaining about teams cheating is more than a bit disingenuous if any of the stories about them “giving the call” to particular teams, or even their “legal today, banned tomorrow” regulatory shenanigans are to be believed.

    • Thank you, Ray. Indeed cheating is cheating. Those who choose to justify their ethics by the imagined reactions of others, rather than by their own honesty, will be left to ponder over the years whether they really did win the race. They may have crossed the finish line first, but that doesn’t mean they won. They merely stole a “win”…and they’ll always know it.

    • Hi Art, well, hold on a sec, I do agree we’re losing some morals, I was taught the same as you, and tried to teach my kids the same, but I see this as a competitive edge not cheating. Drag racer John Force had like a 7 year winning streak, because his crew chief designed a better clutch and intake manifold and dusted them all, now they are the standard. He wasn’t cheating, just trying to win, and eventually, the rest just caught up with him. Lying on taxes or to a spouse is one thing, but a better race car engine, or whatever, I feel, is fair game.

      • I don’t think anyone is saying being the first to design a legal (or at least not specifically illegal) part is cheating.
        We are talking about purposely using a part that is specifically banned knowing it won’t be discovered in a post-race inspection.

        Races have often been won by innovation.
        That’s legit. It’s been that way since the days of Barney Oldfield and the Peerless Green Dragon.

        Now sometimes a sanctioning body will retroactively ban something that was legal in an attempt to level the playing field or to keep speeds down in the name of safety. That’s an entirely different subject.

        • Ethics are what you do when someone is watching.
          Morals are what you do when noone is watching.
          But that full roller crank for a big block sure is nice!

  6. Thank You for this story. Not only is this brilliant, but I’m sure it wasn’t successful in it’s first few attempts. Perseverance pays off. If it was easy everyone would have been doing it.

  7. I quit watching Nascar because all the cars were built same-o, same-o and the only advantage was one of the drivers got a lucky break in a “left hand turn”! Otherwise, it was a “race” of four wheeled billboards!

  8. Good grief, you guys are really going over the edge about ” morals.” If it’s not outlawed by the rules it should be legal according to one guy from Florida. Things like 2 inch fuel lines or drilling holes in the carb studs to get more air in the engine will be tried until a rule is made against them, and I like the way they think. Instead of NASCAR telling us how they caught someone cheating they should tell us how. Maybe I would still be watching. Thanks David for an interesting subject.

  9. Without us knowing the exact rules, it’s not possible to define this cheating. Were stock crankshafts actually required?

  10. When it comes to world championship racing, it’s only cheating if your caught. That’s the hard truth of the matter. Been there, done that………..and we passed the tear down test every time also…………we were able to develop 14 percent more horsepower to the rear wheels, and were never caught. It made up for driver mistakes and on the straights we could pull two or three lengths ahead of all the others. Trick was to make it look like skill………we ran this way for two years. It is what it is……….Ed

    • Sorry Ed, but NO. As a former race driver and tech inspector, this is a major violation of stock car rules. Stock, car, get it? the car had a plain bearing crank and they show up with this (though it’s not innovative, 30s Bugattis ran roller bearing cracks)? Out on your ass disqualified, banned for the season disqualified. What do you think those other boys are doing risking their lives, mortgaging their homes trying to beat a GM engineer that uses corporate money to win over some low budget teams who believe they are contenders when they are running around in circles? The Smokey Yunick-glorifyimg spectator is just clueless as to what real racing is about.

  11. I wonder how they built enough oil pressure to maintain the main bearings? It doesn’t seem like they could have used an iron block saddle as an outer race for a roller bearing. Also if a tech inspector saw the oil pressure gauge with the engine running, he would have smelled a big rat.

    • Very little pressure or volume is necessary with ball or roller bearings and too much oil can overheat them in an engine. The five double-row roller main bearings are positioned on top of the outer main bearing races in the photo.

  12. As everyone knows, NASCAR has it’s roots in running moon shine, where the local cops were always just a couple moves behind. Modifications to thwart the law gave an edge.

    Looks like that early spirit of clandestine engineering was merely carried over when they moved to the race track. Smart guys win, but getting caught is a punitive expense.

  13. After posting, I went back and stared again at that engineering marvel in the photo. I can’t imagine how many hours went into making that just for a few more revs on the competition. Mickey Thompson once said “the only faster than cubic inches are rectangular dollars”.

  14. Thanks for sharing this little bit of history. I’d love to see some frame and suspension tweaks they did to the early NASCAR vehicles.

  15. This is a very interesting topic. Without making any moral judgements, I am fascinated by the creativity , the methods tried and whether they were successful in creating a technological edge. Drilling holes in carburetor studs? Clever!!! I was totally unaware. I would love to see more articles/photos like this. Great Job!

  16. I have a buddy of mine that built a 273 Mopar in I believe the mid 70’s with split roller bearing rods and mains. He ordered the crank out of the back of Hotrod mag. for $500. It came with crank, rods and roller bearings. He used to street race it and said it would turn up to 8500 in the blink of an eye. It only had about 10 psi of oil when idling and 40 when it turned up. Anytime the oil would start turning brown on the dipstick he would change it. He ran a couple years before he ended up selling it.

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