12k rpm 289 cuin

[bentvalves]

you guys ever see anything like this local to you?

https://youtu.be/xv251lDtGu0

would love to know what it takes to spin a v8 to the moon like that.

[englertracing]

I suspect with a nice crank, rods, and pistons that, that rpm isn't a huge issue with that type of stroke.

The valvetrain is the trick.....
Cam lobe design critical
Ti valves absolutely required
Probably some trick ass ultralight non adjustable rocker arms.
Mongo valve springs.

And..... tons of Spintron time to make it all play nice togeather.

[lefty o]

good valve train, and good rod bolts. ive had 327's over9, and i dont think id could handle hearing a small block spin faster.

[1972ho]

Wow and bracket racing it to boot.

[panic]

W/r/t rpm isn't a huge issue
What breaks the rod?
RPM^2 × reciprocating weight.
2.875" stroke @ 12,000 RPM is not 50% more tensile load than 8,000 RPM, it's 125% more.

[PackardV8]

As someone who built his first 289" in 1966, does anyone think a 12,000 RPM 2-valve pushrod engine is state-of-the-art?

FWIW, I had a similar conversation in the 1970s with a guy who wanted me to build him a 221" version, the first SBF. "I just wanna beat them with small cubes and really high RPMs." Even then, I told him "High RPMs are the most expensive horsepower. Spend all the money you want and still lose to a 302" who spent half as much." Today, I'd say a 331" or 347".

[BOOT]

289 @ 12k is moving bout the same air as a 434 @ 8k

[PackardV8]

289 @ 12k is moving bout the same air as a 434 @ 8k

Or wishing it could.

[77cruiser]

Used to see one close to that at BIR many years ago, early 60's Vette 292 ci. I think, claimed to leave @ 11000. Pouty Mouse was the name on the car.

[Krooser]

We had a healthy 289 in our dirt sportsman car in 1970.

My friend Louie, who drove the car, had accidentally installed the 2-3 shift lever upside down on our 3 speed toploader.

During the start of the feature he realized his mistake so he pulled back on the shifter and hit 1st instead of 2nd. Ran 25 laps in first with a 4.11 gear... we never went faster, the car took a set in the corners without brakes (just a blip on the throttle) and we damn near won the main!

Never hurt the motor afaik.

That old Ford sounded like a Novi at Indy....

[af2]

That is bad ass! But my wallet says 9k max. Hopefully soon we will be back out with the Willys!!!

[af2]

As someone who built his first 289" in 1966, does anyone think a 12,000 RPM 2-valve pushrod engine is state-of-the-art?

FWIW, I had a similar conversation in the 1970s with a guy who wanted me to build him a 221" version, the first SBF. "I just wanna beat them with small cubes and really high RPMs." Even then, I told him "High RPMs are the most expensive horsepower. Spend all the money you want and still lose to a 302" who spent half as much." Today, I'd say a 331" or 347".

Jack how about 380" at 9500 to 10000 old one. Or the new one at 403" and 9000?

[englertracing]

W/r/t rpm isn't a huge issue
What breaks the rod?
RPM^2 × reciprocating weight.
2.875" stroke @ 12,000 RPM is not 50% more tensile load than 8,000 RPM, it's 125% more.

Compared to when prostock was turning 12k+
(I heard 14 but seems like a stretch) With a 3.5" stroke and a 4.750" bore
Probably makes the 2.875 @ 12,000 look pretty good

[bentvalves]

are those 289's 2 bolt main?

[BOOT]

are those 289's 2 bolt main?

It's prob an aftermarket block