Something weird going on

[734406pk]

ya, leak down test will be a good idea if necessary.

Yeah maybe, i don't think it's that serious, but be prepared for the test. I still strongly feel the issue is in the idle circuit, but whatever it is we will find it.

[cudabob496]

Yeah maybe, i don't think it's that serious, but be prepared for the test. I still strongly feel the issue is in the idle circuit, but whatever it is we will find it.

exactly what I've felt too, but I replaced the metering blocks, since the existing
ones were 15 years old, and known for warping.

[734406pk]

You have pretty much done all you can with the carb. It might be time for a replacement, possibly.

[cudabob496]

You have pretty much done all you can with the carb. It might be time for a replacement, possibly.

Juat got the new valley pan. The kind that allows you to only use paper intake gaskets,
instead of that full metal Mopar pan.

[734406pk]

Nice! Let's see if anything changes.

[cudabob496]

Well, cwap, this tray seems to cover the bottom 1/16 of the intake ports.
Not sure if I can make it work with the paper gaskets and M1 intake or not.
May have to buy a regular Mopar metal tray.
Think I got a bunch of BS from folks selling this tray.
Maybe I can modify the tray?  Will fool with it for a little while.

[734406pk]

Isn't the valley pan on upside-down? The raised flange that's interfering with the intake goes under the head?

From 440source:

   

Sheet Metal Valley Pan - RB Engine - Single Plane


Sheet Metal Valley Pan - RB Engine - Single Plane
Item Number: 127-1009

Unit Price: $28.95

In Stock


Quantity
1
 
 Detailed Description
Our fabricated sheet metal valley pans work great with our aluminum Stealth heads, Edelbrock RPM heads, or any other aftermarket heads which feature an unbroken deck surface where the lower edge of the head's deck surface meets the edge of the valley pan. They will also work with factory cylinder heads, however there may be a small gap where the lower deck surface has a break which may need to be filled with silicone, depending on the intake manifold you are using. The pan is shown upside down in the picture. When it is installed, the "lips" along the long sides will fit underneath the edge of the cylinder heads, making a tight seal and allowing the use of standard intake port gaskets. This pan is designed to work with SINGLE PLAIN INTAKES only. Dual plane intakes (including stock units) will not fit due to the exhaust crossover which hangs down underneath them. We do have some other models which may work if you are using a dual plane intake Because this pan is a single solid piece which fits "under" the cylinder head intake face edges, it requires at least one cylinder head to be off during installation or removal. Supplied in a gold irridite finish for good looks and corrosion resistance. We carry these in two different versions, one for the "RB" (413/426/440) engines and one for the "B" (361/383/400) engines. Be sure to select the correct one for the type of engine you are working on.

[cudabob496]

Thats what I was expecting, but if you turn the pan
upside-down, the holes in the pan will not line up with the
holes in the block at all. Way off.

[734406pk]

Could the manufacturer have bent the flanges backwards? It sure seems that way.

[cudabob496]

Could the manufacturer have bent the flanges backwards? It sure seems that way.

Its a sturdy 1/8 inch piece of aluminum. Its about 1/2 inch wider than the engine valley, so even if flanges
were bent in opposite direction, would not fit. As it is, it fits nice and snug, but the entire side lengths protrude
into the head about 3/16 on an inch. My M1 is flush with the side of the valley when installed, so this plate would
interfere with the intake too, and the potential for vacuum leaks and oil leaks is bigtime. Its advertized to work
with Stage VI heads, but that must be a misprint. Guess I'll go the old fashion way. If a new intake gasket does not solve my problem, only other
possibility is viton float needle/seats. If new seats don't fix it, maybe I can send carb into Holley for inspection.

[734406pk]

The problem with the one piece valley cover plates is that you have to pull off one cylinder head to install them. It doesn't look like that valley cover plate is going to work no matter what you do, so you might as well go back to the old system. 2X .015" gaskets plus the stock style valley cover/gasket. Sometimes the intake manifold needs to be milled to fit with the added gaskets...

[734406pk]

Here is the two piece valley cover plate:

http://www.hughesengines.com/Index/products.php?browse=category&level0=RS0gQmlnIEJsb2NrICAoUmFpc2VkIERlY2sp&level1=R2Fza2V0cyAmIFZhbGxleSBQbGF0ZXM=&searchmode=partnumber&page=4&partid=24085

[cudabob496]

Here is the two piece valley cover plate:

http://www.hughesengines.com/Index/products.php?browse=category&level0=RS0gQmlnIEJsb2NrICAoUmFpc2VkIERlY2sp&level1=R2Fza2V0cyAmIFZhbGxleSBQbGF0ZXM=&searchmode=partnumber&page=4&partid=24085

Looks great, but won't work with my stage VI heads, based on photos I looked at.

[734406pk]

OEM style gasket/cover plate then. Does your intake manifold allow you to install 2- .015" gaskets on each side?

[cudabob496]

OEM style gasket/cover plate then. Does your intake manifold allow you to install 2- .015" gaskets on each side?

oh ya, used two .060s already on each side, due to some slight misalignment between head and intake surfaces.