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Village Idiot
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You got lucky. Hope you can get it back together here pretty quick. Other than the valve, what all got hurt?

Paul
 

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B-Killer
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Discussion Starter · #4 ·
Yeah, huh. that valve is in #1 and the plug came out of #7. Only 7 showed lean, I'm using Vortec heads and manifold and now believe I may have had an intake gasket leak. But I'm gonna fatten her up anyway. Don't know why that valve was bent. Following the removal of the plug, I found only 30 PSI compression in 7, but after taking off the head, no piston or valve damage on that cylinder, but looks like rings failed? Further dis assembly tomorrow, but a new block and pistons are likely which will fix the problem of having to buy $300 .090 head gaskets to "correct" the zero deck block. Then a valve job should get back the 1/2cc I'm missing in the heads to be legal, they cc at 63 1/2 after light milling. I want to be LEGAL for Burley and if this thing will run for the whole weekend it was proving to be very fast at Sammamish.

Bob, your thoughts?

Here's the whole set of plugs with the front of the motor nearest.
 

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Village Idiot
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3,564 Posts
I might try to go with a non projected tip spark plug. It gives a little less of a chance to start a detonation problem. Did you roll the engine over after leaking down #7? I have guide issues before where it would leak some by a valve, and after spinning the engine over a few times it would go away as the valve would seat better some times. Let us know what all you find.

Paul
 

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Just Me
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4,107 Posts
What kinds of RPMs and speeds were you seeing before it broke? I have a feeling we'll see a lot of head and valve train issues as people push for the 85 limit.
 

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B-Killer
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199 Posts
Discussion Starter · #8 ·
It never got above 5200, I had an electrical issue as well. I got a DUI unit installed in the HEI and then started the motor and heard the dead cyl. and started pulling plugs then compression etc......done. For 5200 it was running (classified) :) MPH.
 

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What compression, What timing, What spark plug, What carb, What manifold, What fuel?????????? Maybe we can help with a little more information, for those of us that don't know your program!!!!!

Sorry to see you have issues before a race! A lot of people keep leaning the motor down by reading spark plugs and get into trouble like you did, especially with the lack of compression! Running the program on the dyno is plus so you can figure all of these things out Prior to testing or racing!

Good luck!
 

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B-Killer
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199 Posts
Discussion Starter · #10 ·
.030 over 350 with zero decked block + .090 head gasket and 63 1/2 cc combustion chamber (will hog that out to 64 with a new valve job) I dont know the math to figure Comp ratio, The only carb we can run is the 600 holley mine has the choke horn milled off and flows 670 on a bench with internals that meet the rules, Edelbrock RPM Air Gap manifold (dual plane). 10 degrees initial and 32 total timing.

I'll listen to any input but I think an intake leak and wrong jetting was the killer. Hope to meet some of you in Burley.
 

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I asked so many questions because there are so many variables!! If your only running 32 for timing it may have been a carburetor problem or a vacuum issue. The end runners of your manifold may run a little leaner because they are lazy. Also if the floats are set too low and or jetting, fuel pump not delivering properly, etc. I hope you have some good knowledgeable help close by guiding you through your investigation?

Good luck and keep us posted as we'd like to know your findings!! See you in Burley>>>>>>>>>>>>>>>>

:airplane:
 

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I have been playing with the Vortec heads for years now...

You have a potential rocker arm problem like a bent stud or a tight guide. The exhaust guides need to fit pretty loose if running sustained RPM, especially if running the motor really cool and lean (I know the lean condition was not intentional)

Also, have you verified the cam timing?

Just some off the top of the head thoughts. Running retarded ignition timing will do strange things too, but it sounds to me like it was running "too" good. ;)

That exhaust valve looks funny to me, not funny haha, funny queer...:grin:
 

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You need math to figure C.R.? Who knew. With the chamber at 64 you're right around 9.2 depending on the valve notches in the pistons.

FC Pilot is dead on. Can those POS projected tip plugs. You going for a smog check or trying out for a milage marathon.

I'd say you you some how managed to detonate #7. Like you said, the rings are probably toast and causing the leak, probably lifted the head enough to blow a path for the water, or, as you said, the manifold was not only not sealed to the outside world, it wasn't sealed to the neighboring water port.

Like GT Jets said, the guides are probably tight and you hung #1. No sure why he thinks it looks queer. Its looks bent and it looks like it was kissing the piston even after it bent.

I guess this class is a great learning curve to racing. You, Shawn, and Marissa, and who ever else are lucky these were SS PS GN or cracker engines.
Just because they are basically warmed up stockers doesn't mean you can assemble one and tune on like the family grocery getter.

GET RID OF THE PLUGS!!!



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You need math to figure C.R.? Who knew. With the chamber at 64 you're right around 9.2 depending on the valve notches in the pistons.

FC Pilot is dead on. Can those POS projected tip plugs. You going for a smog check or trying out for a milage marathon.

I'd say you you some how managed to detonate #7. Like you said, the rings are probably toast and causing the leak, probably lifted the head enough to blow a path for the water, or, as you said, the manifold was not only not sealed to the outside world, it wasn't sealed to the neighboring water port.

Like GT Jets said, the guides are probably tight and you hung #1. No sure why he thinks it looks queer. Its looks bent and it looks like it was kissing the piston even after it bent.

I guess this class is a great learning curve to racing. You, Shawn, and Marissa, and who ever else are lucky these were SS PS GN or cracker engines.
Just because they are basically warmed up stockers doesn't mean you can assemble one and tune on like the family grocery getter.

GET RID OF THE PLUGS!!!

Probably should have clarified the queer valve :)violent I was referring to the rusty number 7...hey, isn't that an adult beverage? :)Unsure

It almost looks as though number 7 was pumping a lot of water....What do the cylinder walls look like?
 

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Premium Member
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Probably should have clarified the queer valve :)violent I was referring to the rusty number 7...hey, isn't that an adult beverage? :)Unsure

It almost looks as though number 7 was pumping a lot of water....What do the cylinder walls look like?
I think the #7 valve looks like that for the same reason the plug from that hole does. He either banged it pretty good and it came thru the head gasket, or possibly a leak from the water port to the intake port. The manifold gasket may have played a part in the lean burn as well.



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OH sorry

It just cant be said that there is NOT GOOD information to be learned here, thanks Mel for sharing, possibly others can avoid this when deceminating the great advise.
 
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