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Discussion Starter #1
Well, the numbers don't lie....

#1 165psi
#2 175psi
#3 162psi
#4 150psi
#5 172psi
#6 170psi
#7 157psi
#8 165psi

There was a little bit of oil on the threads on cylinder #'s 2, 6, and 8. Cylinder #8 spark plug looks awful. It is all black and cruddy looking. All the others are very light brown, if not still white.

So, oh wise men (and women) of the VMF, what does this tell you?
 

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Ahhh.... you need to replace your #8 plug?

Just kidding. With those cylinder pressures, it looks like you have a moderately high compression ratio. #4 is a tad low compared to the average of 170 psi or so. I cannot say that know if that is the source of your problem.

If no one can come up with a the cause, you could cure the symptom by cutting off part of your valve cover oil filler tube and installing one of the push on vented caps, assuming the diameter of the tube is about right. Releaving some pressure should help.

Check your #8 plug wire to see if that was the cause of the fouling.
 

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there are all within 10% PSI so that is good. Oil on the threads does not mean much to me. I would suspect that #8 has a leaky valve seal and letting some oil in along the stem. In summary, I do not see any real issues. Am I missing something?
 

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Why not pull your oil filler cap and take it for a test drive. If that helps, then you might think about changing/modifying the valve covers.
 

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Discussion Starter #10
The Rubber Glove Test!

I fired up the engine and took the oil filler cap off. I then took a rubber glove (the surgical type), and fitted it over the oil filler tube on the valve cover. At idle it gets sucked in to the valve cover. At about 2500rpm it starts to fill, but nothing more than a flacid glove. At high revs it starts to inflate quickly into a balloon.

Maybe I do need that breather....

I just went back and did it again. The glove stays deflated at normal rpm's, even at 3000rpm sustained for about 10 seconds, no dramatic change. Right at 4000rpm the glove pops up and inflates quickly. I held 4500rpm for 5-6 seconds and the glove popped.

Before the glove popped I tried it with the PCV disconnected. Above 4000rpm it inflated just enough to take its shape, but didn't inflate like a balloon. Breather time....
 

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Dave,

I have found that even though the plugs are new doesn't necessarliy mean that they are good.......

I will get back to you on how to test them.

This way you won't get any dead cylinders.....

Yes also get the breather type oil filler cap...
I stayed with the sealed type along with the PCV stuff that vents into the shaker air cleaner.

I would also recommend using some oil treatment like restore
and then recheck your compression numbers.

I will also be posting my compression check numbers pretty soon.

We will be re-dynoing the stroker after the mods to the holley are complete, torque should jump up like crazy..

anyway talk to ya later!!
see ya at mini nats!!!
 

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Get a puke tank and lose the PCV setup.

Change the valve covers to add a breather on both sides and route both to the puke tank. If you just put breathers on you will get oil all over you valve covers (ask me how I know).
 

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Maybe I do need that breather....

yeah, don't we all...*G*

Ever tried using an old smog pump to suck the crankcase vapors out....

Oops...another street racers trick...hey, the pump is on and working...

heheh
 
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