I know what valve float is but I want to make sure before I change my valve springs. I don't have a tach in my Torino. But in every gear winding up it hits a certain spot and just bottoms/flattens out till I shift to next gear. This is a cleveland and should wind pretty high or higher than it is.
So if this is what valve float acts/feels like in any FORD I would like to know. Thanks, Warren. I don't have a rev limiter so I don't know what that would act like if I hit that

68 Torino GT S code 390 fstbk
70 Torino GT 351cl 4spd
71 Torino Cobra 429 C6

I suggest you spend money on a tach before stronger valve springs. Oterwise you will start to hear loud noises, see smoke and a trail of broken parts & oil behind you.

It sounds like your engine is just running out of breath. jmo. ww

1965 Galaxie 500XL 445ci Stroker (soon) C-6
1965 Galaxie 500XL 390ci P-Code, 4-Speed
1965 Galaxie 500XL 289ci Cruse-O-Matic
2001 Ford F-150 SuperCrew 5.4L
2006 John Deer X320 Garden Tractor

the valve cutting thru the head and block into the water jacket!!

agree with warren buy tach find out were you are in rpm 1st!

a lot like hitting the rev limiter on newer cars. Like the others though, I would highly recommend a tach. RonW

It kinda goes like this. Loud screaming high pitched, then the
clunk bang, or bang clunk boom. Then you can see into the block
thru the outside. Lots of stuff comes out of the motor.

N/M

68 Torino GT S code 390 fstbk
70 Torino GT 351cl 4spd
71 Torino Cobra 429 C6

It just kinda goes flat. Ignition and fuel stuff can also do that - but if its springs you'd best check/fix them soon. As noted - it can get expensive...

Barry Rabotnick
Survivalmotorsports.com

When an engine goes into valve float, cam timing is lost. The valves are not under any effective control; which means the likelihood of a valve "kissing" a piston is greatly increased with resulting carnage as 'little' broken parts, hit bigger parts which leads to even more damage.

As I am sure you know, 2 objects cannot share the same space / time concurrently. The dance between valves and piston is controlled by the cam, which in turn is aided by the appropriate springs (of correct materials, configuration, design and strength to offset the weight of the valves when moving at a given (maximum) rpm). You can't just put the biggest springs on the valves you get stuff under a valve cover and expect it to live very long - 'cause you also have to worry about premature wear on the cam lobes). Bottom line, get the proper springs to handle the expected rpm based on cam profile and component configuration and weights. Make the valve train a light as you can afford (lighter valves, lighter springs/retainers/rocker arms carry less momentum are easier to stop/start as they follow the cam). Finally, once the valves go into "float" the next time, generally, it'll happen at a lower rpm...something to do with metal fatigue, harmonics - other stuff I don't have a clue about.

You don't want to mess around at the extreme edge of your combinations limits. Suggestion, change the springs, lower your expectations - or buy and install better, lighter components.

 

PS: Oh yea ... get a tachometer!

or as it was otherwise known a Spintron.
Things I remember was there was no noticeable extra noise but with clear valve cover tops the strobe lights on the valvetrain the retainers started spinning around darn fast when Float started. Smokey mentioned the springs would get hot fast while in valve float. That pretty much explained to me why FoMoCo put Spring Seat Cups on numerous HiPo 429PI,CJ,SCJ/460PI and HiPo Clevelands I've torn down.
I think there's a decent magine between floating a valve and punching one into a piston

So, I guess the issue is whether its "more likely" for valve to hit a piston when its Not under control (given the shorter window between timing events - piston comes up, cam profile ramps down, spring pressure overcome momentum, valve closes...). The higher the rpm, the smaller the window and lower tolerance for error.

My guess is Smokey was illustrating the problem by being able to demonstrate it at will - looking to find a solution, rather than saying it wasn't an issue? But then again, I ain't Smokey ...

of the cool factor he also had glass windows in the crankcase and as with the retainers/valve springs with the strobe it put on a heck of a show. Thinking about Smokey I'd bet he had plenty of valve relief in that Demo Long Block.
I'd agree with you exactly

"My guess is Smokey was illustrating the problem by being able to demonstrate it at will - looking to find a solution, rather than saying it wasn't an issue? But then again, I ain't Smokey ..."