Well.....it's official.....

-

Scotty

Active Member
Joined
May 23, 2004
Messages
27
Reaction score
0
I hurt it. Yesterday in my one and only qualifying pass at the Clobberthon at Houston Raceway Park I bent an exhaust valve. I would have been right on the mark with what I did to slow the car down a little so I could run the 7.0 Real Street class. I went a 7.006 in the 1/8th. Perfect, up until around the 1000' mark. (it's only an 1/8th mile event, but I wanted to see where it was in the 1/4) That's when I heard a high-speed miss and after that it fell off. After limping it back to the pits, James and I pulled the valve covers to check things out. I was really hoping it was only a bent pushrod or something simple. I even keep a spare pushrod in my box. Everything looked fine and we were a bit puzzled until I noticed that the #1 exhaust valve was hung about a 1/4 of an inch open. My timeslip is below. Don't look at the R/T, I was only worried about hitting the changed shift points and not breaking a 7.0. That stinks. :evil:

timeslip2.jpg
 
Don't know if I'll do that just yet. I think I'm gonna fix the valve and switch back to 1.5 rockers on the exhaust. Way cheaper that way. I don't think it'll fall off any on performance. If it does, it shouldn't be much. It's been running too good to go through any major upgrades right now. This is the second time it's happened. I switched to a thicker Cometic head gasket and I have a bunch of runs on it that way. Never had any problems until yesterday. The thing that kills it is the weird profile on the cam. It's a custom ground CompCam and the exhaust profile keeps the valve close to the piston. On top of that my heads are milled .070. Kinda makes for a tight squeeze. The cam is awesome, but my clearances are TIGHT.
 
that sucks scotty i hate to see a Mopar fall!hope its fixed soon!good luck keep us posted :lol:
MIKE
 
Sorry to hear about the bent valve.. I had a decent day yesterday, I finally won my first 2 rounds since I have gone back to racing this year. :D Also won one round today!!
 
Scotty...I bent a pushrod a few years ago..and just replaced the pushrod and thought nothing else about it. Welll at a Mopar King of Street race the next year....I broke a valve....guess what cylinder. The same one as the bent pushrod the year before. I never thought to see why I bent the pushrod.

Take a few little bit more time..and see why possibly the valve broke if you can determine that.

Just my .02

-Eric-
 
The last time I bent a valve was because of the yoke on the rear end coming apart off the line. Since then I truly believe in rev limiters :eek:ops: The head of one exhaust valve was in the collector and three pistons were shattered :cry: At least I had an excuse to build a new motor, that one was a stock low compression 340 :D
 
Hawaii...just have to becareful...I have seen cars rev so fast that the chip doesn't catch the motor. Rare...but it has happened.

I have been lucky ever time I broke something in my drivetrain....on NOS noless...I caught the motor before it hit the chip. I know....cause my tach has a tattletale recall feature. Kinda like the on in the "Days of Thunder" but better looking Autometer Tach. 8)
 
I'm pretty sure it was a clearance issue. I knew it was tight when I put it together, but I didn't think it was THAT tight. Guess I was wrong!! :eek:ops:
 
what were your clearances and tell us about that voodoo sounding camshaft. what are the specs and what is it in?
 
Man, this is an oldie. Scotty has completely redone his motor since this was posted nearly 17 months ago. And from what I saw on mopartech.net, Scotty's home was nearly destroyed recently by hurricane Rita. So I doubt he will be able to respond to this any time soon.
 
-
Back
Top