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You do not have 245 psi. On a pump gas engine with a fairly large hydraulic roller, you will see about 170-180. I think your 180 psi number is correct and the others are incorrect. Were you holding the carburetor wide open when you did it?
On the valve guide clearance, the only way to do this properly is to use a micrometer to measure the diameter of the valve and then use a bore micrometer to measure the guide clearance. A brand new guide/valve will have a lot of wiggle in it because the clearances are .0015-.0020 right off the bat. A clearance of .030" or .040" is THIRTY THOUSANDTHS or FORTY THOUSANDTHS and is not correct. |
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I've made a video about my guide wears but cannot post it here. As I said.. I've got .030" to .040" wears !!!!! |
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If the valves can be noticeably moved side to side you probably have worn guides and they would be the source of the oil entering the intake ports. If we accept the worn guides answer to the What question, the questions that remain to be answered are the Why did they fail and the How to fix questions so as to avoid a repeat performance. BTW .003 to .004" stem to guide clearance while not desireable, on a street driven car it is also not that bad. The amount of oil you are showing in the ports belies .003 or .004" clearance. Ed |
The OP post a "spark plug" gap clearance on his valve guides. Post the YouTube.....gotta see this.
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OK thank you PATRICKT, here is the video.
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Uhhh, that's kinda loose.:JEKYLHYDE
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That's a new one for me. Never seen anything like that.
I've heard of guys having a microscopically incorrect surface finish on the valve stems that acted like a file over time, but I've never seen that before. I also know that GM had a batch of bronze valve guides that were incorrectly hardened on the Z06 Vette several years back. It accelerated the wear. I'd change the guides and valves both. It will need a valve job as I imagine the valve head has been dancing around on the seat. |
I'm surprised the valve heads haven't snapped off from bouncing off the seats at random angles. And how it even got compression test numbers like you have.
Regardless, your valve guide clearance is the largest I have ever seen on any engine in my 40+ years. So what rocker gear are you using? Are the valve guides truly round or oval? Gary |
Valves, guides, and valve job is pretty cheap in the grand scheme of things.
John |
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Just a few reasons that excessive guide clearance happens------wrong valves, wrong guides, incorrect rocker/pushrod geometry---- mix up of standard and metric specs---example would be use of metric valve stem and standard size guides-or wrong size reamer or hone for finishing the guide---wrong valve length to accominate springs/retainers causing issue with rocker geometry/pushrod lengths---
show us some of the seals and also port area near wear push rod is------- angle of engine mount can cause poor drain back of oil in some cases ---- high volume oil pumps and lack of control of oil supply to rocker shafts can cause high oil level in valve covers----- Also in that video it looks like those guides are too short-barely above head mass------ I'll see if I have time to photo graph some of the equipment needed to measure valve guide clearances--- also the diamond guide reamers for the guides-------- |
The good news is that you have the answer to your original question !
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Today I brought my heads to a racing engine specialist and discussed about the valve wears.
For him my problem can be: - Bad/wrong valve guides machining when heads have been built OR - too much camshaft lift incompatible with heads can accept. Edelbrock RPM Performer heads allow .600" maximum valve lift. FOR BRENT: Do you have my camshaft specs when you built the engine ? I don't have any specs or camshaft reference. Thanks, OliveR |
Ok, here's where it's gonna get muddy, because you're taking it to the wrong people and getting incorrect information.
These were not assembled heads from Edelbrock. They do not have Edelbrock valves, springs, or anything else. These were bare Edelbrock castings, CNC ported by KCR, fitted with valve guides and valves there, then assembled by me with the valve springs to match the camshaft. I do not have your cam specs. |
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- You said Edelbrock didn't assemble the heads meaning that different people have work on them. ==> Are you sure that valve guides have been well installed ? ==> Are you sure that valve guides have been well machined ? ==> Are you sure valve job has been well done ? ==> Are you sure that valve lift don't go beyond heads maximum specs ? spring too soft ? What I'm looking is a solution to my problem and today I have no reply. I can replace guides but will it be the solution for long term ? GETTING MY ENGINE IN THAT CURRENT CONDITION WITH ONLY 13000 MILES ON IT MEANS THAT THERE WAS ASSEMBLY FAILURE / BAD COMPONENTS ! So after having spent $18000 on it I suppose I can have little more help from you.... I don't ask you $$$... |
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