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knock knock


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Thanks Pete,

 

I was looking forward to the first race of the year next weekend. I was cuttin' consistant .520 and .530 lights the other night practicing.

 

Bad thing is I just spent about the last of my "mad money" on my trailer so I'll be scraping for the rebuild.

 

I had thought about putting a basic 400" SB together for the torque benefit... hmm??

 

No knock at idle or low rpm, knock at rpm and increases with rpm.

 

 

 

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RickB@DragRacer.com

280V8

http://www.rickb.racemail.com

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I'd double check the timing and fuel quality I had similar symtoms in my 72 pickup w/an old 350 turned out my cheap brother had filled me up w/ low octane and gave me a bad case of preignition(I had upped the timing a bit) just my 7.25cents (had to adjust for inflation) worth

 

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rx7260z@yahoo.com

Speed Power Performance& Style. What else is there?

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Rick it actually sounds like a collapsed piston... rods usually knock at idle more beause of the lower oil pressure. If you caught it early enough where it didn't score the cylinder you may be able to just hone it a little and throw a new piston in... Does your motor have cast pistons??? If so you found the weak one.... Have you isolated which cylinder it is??? This may be cheap to fix....

 

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Remember it is only a piece of metal.

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Ray...thanks for your response.

 

Question...yes, i have cast pistons (as far as i know?). If the piston "collapsed" then wouldn't I have some smoke as an indicator?

 

I plan to get it up to a friends shop so i can put it on a lift and pull the pan. First I will pull a plug wire at a time and see if thast takes the load off a cylinder so i can isolate it.

 

Actually, i think I'll make this a new thread.

 

thanks again,

 

 

quote:

Originally posted by Ray:

Rick it actually sounds like a collapsed piston... rods usually knock at idle more beause of the lower oil pressure. If you caught it early enough where it didn't score the cylinder you may be able to just hone it a little and throw a new piston in... Does your motor have cast pistons??? If so you found the weak one.... Have you isolated which cylinder it is??? This may be cheap to fix....

 

 

------------------

RickB@DragRacer.com

280V8

http://www.rickb.racemail.com

 

[This message has been edited by RickB (edited March 12, 2001).]

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