Alvin removed two valves from the new head to inspect the seats and the valves themselves.

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  • Alvin removed two valves from the new head to inspect the seats and the valves themselves.

All of the valves looked very good in the old head. Alvin could see some signs of water leakage into three of the cylinders under the new head, and one of the new valve faces showed some rust. The seats of the valves and the heads were perfect.

We suspect the leakage is from re-using the MLS head gaskets during the last rebuild. The head gasket under the old head was never removed from before the dyno testing. I was instructed on how to prepare the MLS head gasket for re-use and followed the instructions. That is the last (and first) time that I will re-use a head gasket.

We also found indication that #8 cylinder is running very lean. Number 1 cylinder is also lean, but not as lean as #8. This has been a problem with this engine since I switched to the dominator/demon carbs. When the engine was built, I had a BG Gold Claw RS 775 CFM carb (like a 4150 Holley) on there and the distribution was great. I upgraded that carb to a 1025 CFM and still had good distribution. This has not been the case with either the Holley HP 1150 Modular Dominator or the BG King Demon 1090. I plan to try some form of stagger jetting to try to correct the problem.

I purchased the new rings and a new set of MLS head gaskets. I had to go back and look at my old 2005/2006 building notes to determine that I have two different thickness head gaskets. The left bank (1-3-5-7) has a .041″ thick gasket and the other side, where the new head is, has a .051″ gasket. This was done to compensate for imperfections in the block deck and the chamber volume of the two heads. The new head is where the leaks occurred. We also found out the new head has intake valves that are made of a different material, where the other side has nice shiny stainless steel valves.

Tomorrow I will start filing rings and remove the pistons one at a time and re-ring the engine.

I put all the new Dart push rod guides on both heads. They have not been torqued or aligned. After they are aligned, Dart recommends marking them so they always go back into the same spot.

August 25th, later – I pulled both heads and decided to re-ring the engine. I am too close to take a chance on $130 worth of rings. All but two of the cylinder walls looked good. The other two needed some Scotch Brite to clean them up. Now all of the cylinders look good and so does everything else.

The painter said it will be, “a little later”… I told him to take his time. I don’t need the car in my way right now anyway, while I do the engine.

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