stangkillin99ss

ok went to the dealership today and saw my engine torn apart. Aparantly i over revved a few times and my pistons tapped my valves. (stock setup) Now my installed (very experienced) told me that with this cam and the lift it has on it (.561) it would be inevitable that the piston is gonna kiss the valves. Has anyone else had this problem with their TR224 cam? Mine is on a 114 lsa.Will i have a problem?? Any help would be greatly appreciated thanks in advance <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

VTtransam

Unless your heads are milled a SIGNIFICANT amount, you'll be fine. I've never ever heard of anyone having PV clearance problems with the TR224 with stock heads. This is an extremely popular cam too, and nobody has reported any issues even with milled heads. My TR224 112 with slightly milled 5.3L heads has no issues.

Matt

stangkillin99ss

Matt,

thanks alot i have never heard of it either but seeing my piston with a nick sort of scared me, i have screwed up from time to time racking it out to 7k+ so its no wonder why they are like that <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" /> anybody else have a problem?

Mike00FRC

iTrader: (1)

Springs?

stangkillin99ss

nope no broken springs or bent valves or bent pushrods ..just nice half circles on my rear piston?? what caused this does anyone know? (besides me being a dumbass)

akw408

It may be valve float at high rpms. How bad was it, did you get bent valves?

stangkillin99ss

nope dont think any of the valves bet car ran strong dynoed 346 with a lid headers and borla. Could you describe the concept of "valve float" for me? thanks

DONAIMIAN

iTrader: (18)

valve float is when the valve dosent close, you rev so high and without enough spring preasure the valve wont close because of not having enough preasure on the valve. Take one of thoes paddles (cam) with the ball and rubber band (spring) on it. do it at a constant speed where you hit the ball (valve) everytime. now all of a sudden go as fast as you can, what happenes, the paddle (cam) somes back and forth and dosent hit the ball because the rubber band (spring) couldnt bring the ball back fast enough so it could be hit so the ball (valve) stays out (open) and the pistons are comming up and hitting the valves before the valve or ball can go back up to the paddle there.
I hope it helps and dosent confuse you any <img border="0" alt="[driving]" title="" src="graemlins/gr_driving3.gif" />

ZEIK 383

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by stang killer:
<strong> valve float is when the valve dosent close, you rev so high and without enough spring preasure the valve wont close because of not having enough preasure on the valve. Take one of thoes paddles (cam) with the ball and rubber band (spring) on it. do it at a constant speed where you hit the ball (valve) everytime. now all of a sudden go as fast as you can, what happenes, the paddle (cam) somes back and forth and dosent hit the ball because the rubber band (spring) couldnt bring the ball back fast enough so it could be hit so the ball (valve) stays out (open) and the pistons are comming up and hitting the valves before the valve or ball can go back up to the paddle there.
I hope it helps and dosent confuse you any <img border="0" alt="[driving]" title="" src="graemlins/gr_driving3.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Very clever explanation! <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

stangkillin99ss

MAN THATS AWESOME!!!! THANKS A MILLION I GET IT NOW!!!

Fly By

or, its just a weak spring. The TR 224 wont have any PTV issues. Hell, a stock cam can do what you did!

stangkillin99ss

Fly By: i know dont remind me ( i did do it with a stock cam <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" />

i am switching to 918's, titanium retainers, hardened pushrods with the 224 setup granted i dont miss any gears i should be absoulutly perfect correct?

DONAIMIAN

iTrader: (18)

correct <img border="0" alt="[driving]" title="" src="graemlins/gr_driving3.gif" />

DavidGraham

Way back in 1967 I purchased a brand new Firebird 400 with a 4 speed. I had no idea what a redline was for, and thus reved the daylights out of it. Knowing now what I should have known then is that valve float is a condition you will enter if you go beyond the specs of either the cam or the springs. I did this unintentionally years later in the burnout box with a 1985 Camaro with the 5.0L in it. Not paying attention to the tach, I reved it and when I looked I was up at 8,000 RPM. It reved so fast in the wet area of the box, unfortunately I did not have a rev limiter. Anyway, after that episode, on the run down the track the car was one second slower and never ran the same again. I pulled the engine, replaced with a 350, and when inspecting the heads on the 5.0L I saw bent valves. The bending was slight, but still was preventing proper sealing.
Anyway, use good springs and pay attention to what the cam mfr recommends for the upper limit. Unless you have deep pockets and can afford the parts.

95 Formula

iTrader: (2)

I've seen the same thing on overrevved stock motors. Every piston had a little "eyebrow" on it where the valve kissed it. Looks like you got into valve float.