Cam degreeing: I USED to think it was a waste, but now IT RUNS !!!

[Kern Dog]

Guys are running at this ratio on pump gas, Cooter.
"I told you so" isn't the way to fix it.
There is something wrong here that is getting in the way.

[Kern Dog]

This morning I found some oil in the valley pan. There was some below the intake and some toward the rear. Also, both valve covers were wet on the sides that face the intake. I Figured that there was some possible oil seepage. The intake bolts felt as if they had loosened up. I was able to tighten them at least 1/4 turn more! I wiped the valley with a rag & solvent.
I rigged up a long fuel line and attached a guage to the windshield so I could read the fuel pressure while driving. I got 7-8 lbs at idle and cruise and at WOT it went down to 5 but didn't go below that. The first 2 WOT blasts actually had NO detonation! I was all wiggly thinking that it was gone!
The next 3 WOT attempts, the detonation came back. At home, I noticed that the valley pan had some oil on it again. I pulled the intake and found oil all around each port. Oil was also around the intake ports on both sides of the valley pan and the heads. I've been pulling oil into the cylinders! Each intake port had oil film on the walls. When I installed the valley pan, I left the paper gaskets out but smeared Gaskacinch around the ports. Obviously it was inadequate. I replaced the valley pan and used the thin paper gaskets on both sides of the ports on both sides of the intake. This made it a bit more difficult to thread the bolts in, but I got it done. I went a bit tighter on the bolts this time. I'll drive it tomorrow and report back.

[Kern Dog]

I am still at it, trying to get the engine right.
I replaced the valley pan. This time I used the thin paper gaskets on both sides of the tin. I replaced the valve cover gaskets at the same time. Unfortunately, all I had here were the flimsy rubber VC gaskets. Here is an odd discovery: The MP aluminum valve covers have a gasket rail that is over 1/4" wider than the gasket rail on the Edelbrock heads. The MP valve cover mounting holes are big enough to allow a degree of slop. THIS caused the squishy rubber gasket to distort, causing leaks on both sides. I replaced them again with the firm black fibrous gaskets. No leaks now.
The leaky valley pan had me thinking that my detonation may have been from oil getting into at least one cylinder. A test drive showed that it still knocked.
I added 5 gallons of 100 octane to about 5 gallons of 91. I estimated the octane rating to be around 95 1/2. Yeah, it still knocked. I drove it around awhile until I was down to about 5 gallons again, then added 5 gallons of Sunoco 110. The knocking is gone and the car hauls ass! It feels faster than ever.
I DON'T want to rely on race gas to enjoy this car. I ordered a Mallory distributor tuning kit and replaced the springs in my original distributor and another MP I have as a spare. I need to wait until the tank is almost dry, then add 91 octane gas exclusively. If i drove it now with the race gas in there, there is no way to know if the recurve in the distributor did anything. I'm not very optimistic though. The full advance is all in by 2000 rpms. If I hold steady at any rpm above 2500, it knocks at WOT. To me, if it knocks at any speed AFTER the distributor advance is all in, then the advance curve isn't the problem.

[Kern Dog]

Hello again.
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UPDATE:
After much deliberation, testing, parts swapping, etc....I decided that the problems that I was having came down to one fact: The compression ratio I had was too high for the 91 octane fuel. TWO options: Use higher octane fuel or lower the compression ratio.
I chose to pull the heads and go with a thicker head gasket to lower the compression ratio. I have heard about all the benefits of quench, but after rechecking the numbers, I found that I was already at the edge of 11.0 to one, I had a quench distance of .051 and no amount of distributor tricks could stop the detonation. Only 110 octane stopped the knock.
I removed the heads and had them cleaned, ported and a valve job done. I cleaned the carbon from the tops of the pistons and rechecked the deck clearance. I thought that I was .017 in the hole but every hole came in at .012. This moved the CR up a bit from what I previously thought. Also, I have had these heads lightly resurfaced approx .005 4 separate times to clean them up after using the Fel Pro gaskets that left a slight imprint after use. The resurfacings also must have raised the CR a little bit. Before, I had calculated the CR at 10.73 to one, but I could have been at or above 11.0 to one. After posting about my intentions to use a thicker head gasket to lower the CR, many advised against it. They felt I was going to lose the "quench" effect. My thoughts? If I had to use a THINNER gasket to gain quench, this meant I was also moving the Cr to the 11.5 range as well. Would this be a smart move? To me, it was a gamble that was hard to feel comfortable with.
The heads measured 83 ccs. This is after several resurfacings AND the unshrouding of the valves, opening up the chambers and the valve job.

[Kern Dog]

The calculations show that with the Cometic .075 gasket, my Cr will be at 10 to one. The .086 moves me to 9.77 to one.
All these moves should improve the driveability of the car. The lower Cr will allow the use of 91 octane fuel and a more aggressive spark curve. The porting will improve power. I sure am anxious to see how much difference it all makes!

[firefighter3931]

Hopefully these modifications work out for you....a one point reduction in compression will make a difference. 


Ron

[BSB67]

It is unfortunate as for a little or no more money, no more work, you could have had 0.040" quench and any reasonable compression ratio you wanted. 

You should be successful at getting ride of your detonation, but I only wonder how much power you've given-up. 

[Kern Dog]

Do you mean by changing pistons? Yeah... I have been stubborn to pull the engine to do that. It would have probably been a better choice in the long run, but that was a move that would have surely cost me $1200 at a minimum when you factor in the pistons, pressing them on the rods, rings, oil, filter, gaskets, engine block honing, cleaning, new cam bearings.... then I'd still need new head gaskets anyway.
This way I at least have had the heads ported which should allow more power for any configuration I ever plan to run.
The machinist did the surfacing, valve job and assembly while another guy did the porting.

[Kern Dog]

He gasket matched the huge 2 inch TTI header gaskets too.

[BSB67]

Do you mean by changing pistons? Yeah... I have been stubborn to pull the engine to do that. It would have probably been a better choice in the long run, but that was a move that would have surely cost me $1200 at a minimum when you factor in the pistons, pressing them on the rods, rings, oil, filter, gaskets, engine block honing, cleaning, new cam bearings.... then I'd still need new head gaskets anyway.
This way I at least have had the heads ported which should allow more power for any configuration I ever plan to run.
The machinist did the surfacing, valve job and assembly while another guy did the porting.

No.  That is not what I mean. 

Have the combustion chambers milled on a CNC to 90 cc.  Anyone with a CNC porting program for the heads can do it. If you have them do the porting, they probably won't even charge you for the chamber, as it will be milled anyway.

[Kern Dog]

I guess I could have gone about it differently.
Living in Northern California, there isn't exactly a reputable performance machine shop on every street corner. I read good things about Dwayne Porter, Jeff at Modern Cylinder Head and Jim LaRoy but my work schedule made it difficult to deal with "out of town" machinists. By the time I was off of work, they were already home for 3 hours.  I was limited to dealing with people locally. I went with a referral from my regular machinist. I like the idea of opening up the chambers and running a thinner gasket though. I'd be willing to spend a few more bucks to have that done if I knew more.....

[Kern Dog]

Just waiting on the head gaskets. I hope to have them this week.