435 horsepower in 1955.....

[Cool Hand Lurker]

I remember an article at the time about the Chrisman flathead V8 making over 400 hp and under 8 seconds at the dragstrip. I think the speed was 144 but not sure. So, yes it did really run..... how long it ran I don't recall.

[Flathead]

"Flatheads battle Rocker Arms for all out supremacy". Quite a story.

[Bruce Lancaster]

At the time of the Chrisman article in R&C there was a widely discussed theory, discussed by and perhaps originated by magazine guru Roger Huntington, that 1-G was an acceleration limit for drag cars. I think the idea was that a car's traction was based entirely on its weight on the tires, so that if more power was introduced at 1-G the tires would simply spin, limiting possible acceleration to 1-G no matter what.
I think the limit worked out to something like 9 seconds and 140 MPH...the Chrisman car (was it with that engine??) ended the theoretical discussion by simply blowing right through the "limit".
Obviously, the racers have never since looked back or worried about the potential limit to their acceleration!

[Pete]

Originally Posted by Bruce Lancaster

At the time of the Chrisman article in R&C there was a widely discussed theory, discussed by and perhaps originated by magazine guru Roger Huntington, that 1-G was an acceleration limit for drag cars. I think the idea was that a car's traction was based entirely on its weight on the tires, so that if more power was introduced at 1-G the tires would simply spin, limiting possible acceleration to 1-G no matter what.
I think the limit worked out to something like 9 seconds and 140 MPH...the Chrisman car (was it with that engine??) ended the theoretical discussion by simply blowing right through the "limit".
Obviously, the racers have never since looked back or worried about the potential limit to their acceleration!

It's called coefficient of friction.
Huntington's theory was based on the tires that were available at the time. Soaking the tires in hydrogen peroxide was one of the first ways to increase the CF.

[ken1939]

Originally Posted by sanborn

Just a couple of comments.

Supercharged flatheads suffer from "Cylinder Head Flex" at high boost. It causes severe gasket blowing and often block destroying----and the head literally melts. If you look at the few "state of the art" blown flatheads around today, you will see thick billet cylinder heads with closed end cooling fins machined into the heads.

And, the sudden torque requirements of today's drag racing creates severe twisting of the crank and flexing of the block. Earlier drag racing didn't have sticky tires or sticky tracks---thus the sudden torque requirements didn't occur---we just spun the tires---and the block and cranks lived, for at least a while.

If we could get the crank/block to live, we could generate a lot of horsepower if we used enough boost and enough nitro---since nitro brings its own oxygen along.

Watching Drag Racing as I have over the years, these comments really have weight with me. With todays coverage you can really get to see the"mess" that is left behind or when things go wrong in a hurry.

I like the super slow mo to show the exhaust and you can see what the engine is doing, and of course when it is not.

Now if we dont loose any more drivers.

[max sr]

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greta discussion, suprising numbers

[LSGUN]

Great thread guys, I have this little book too and was curious about it as well.

[JDFlatty]

Originally Posted by cuzncletus

.....from a FLATHEAD!! I was in the attic and stumbled on some old Rod and Custom little pages. One that caught my eye had a heading of "435 Horsepower Flathead V8". Returning to where it was considerably cooler to read the article, it seems this motor dyno'd at 435 with only 248 cubic inches (.060 over 59a). The motor used a 3-71 GMC and a 50% load of nitro, injectors from Stu Hilborn, and 17.5 lbs. of boost.

The engine was put in Art Chrisman's dragster and was at 140 mph 250 ft. before the traps, where it blew off the water hoses and Chrisman shut it off, coasting thru at 131. It would be interesting if there was a follow-up to what this motor eventually did. The end of one paragraph pretty much echoed my thoughts. "In spite of what the dynomometer proved and the number of witnesses present, the skeptics continued to say; "Impossible-the lower end would never stand it." No details were given of modifications to the block, but I'll bet we've all got the same cocked eyebrow on this one.

The engine was built by Don Yates and a (?) Newmire. (My mind seems to think there was a Leroy Newmire I read about at an early age.) The article was written by Barney Navarro who obviously had a lot of input, and parts, in this engine. No wonder many of these early legends have been beatified in flathead lore.

Anybody got any more links in this chain of history?

The correct name is not Leroy but Bud Newmire and Stew Hilborn built the set of Injectors
Barney Nevarro - Speed Shop that sold the Ardun Flat Head Chassis to my Great Grandfather Earl Newmire, Don Yates worked for Barney Nevarro and helped with the tune up work on the Dyno but he didn't "Build" the engine. Ed Iskenderian built the Cam for it, Stew Hipborn and my grandfather went to school together and later on my Great Grandfather had his own machine company making nuts and bolts and quick pins which happened to be down the street from Barney.

There's more to tell about this story but Yates took the credit for building the engine, which is not accurate. The 435hp, 217cui; roughly 2hp per sq/in and stock bore stroke. The Gilmore Belt Drive idea for the blower came from a boat that was being built for Henry Kaiser which was a Chrysler Hemi powered boat with a Gilmore Belt Drive which my Great Grandfather had machined pulleys and the guy next door had a machine shop and cut the teeth in them. Stu built the injection system, Ed built the cams for it, my Great Grandfather had all the parts sourced or he made what was needed. Definitely a lot of hands that were involved in making this engine, not to take credit away from Yates because he helped with assembly and tuning.

More success, however, came with Beatty who also ran a Navarro-blown ’27 tagged the “Rust Bucket.” The pair also teamed up on a belly tank project, Navarro saying, “Tom lived next door to my shop and had a covered car port where he could do the welding and assembly work.” The tank was powered by a 295 ci ’48 Merc engine fitted with a 4-71 Jimmy producing 10 lbs of boost. At the ’51 Bonneville Nationals Beatty set a Class D Lakester record at 185.80 mph. The following year, despite destroying two engines, five pistons and three cylinder heads, Beatty proved the naysayers wrong with a best one-way speed of 203 mph and a two-way record of 197.17 mph.

My Great Grandfather Bud Newmire, Tom Beatty, Stu Hilborn, Barney Nevarro were all good friends. Hope this clears up the confusion.

[3W Hank]

No matter of HP is use the formula MPH by 1320.
But thoose days that formula did not work vs track, tires, gearing etc.
But today its more easy figure out.
Dyno is just a number, scoreboard talks and ET say ’what could’ be ( if )