Well, I got it down to the ocean, and I didn't pass my sea trials, but it was not a total disaster. The good thing is it always started right away at idle. Before it was like it was fuel starved, and I would have to pump the throttle like crazy to get it going.
So, I started out at 1000 rpm and would check the speed and the temp at 500 rpm intervals. I worked up to 4000 rpm and blew an iridium plug on #2! I brought a spare standard spark plug, so moved to an area that I could safely drift for a while and changed the plug. I worked up again to 3500 rpm and the motor started cutting out, similar to before, as if it was fuel starved (but not sure). The motor didn't stall, so I started out again and it did the same thing at 3000 rpm. Again, didn't die, I just cut the throttle, and it kept running. I limped back to the launch at 2500 rpm and tied to the dock to do a few diagnostics.
First, I noticed there were two puddles of oil, one in front of my intake manifold, and one in back of it. I brought my vacuum tester, and the vacuum was good, about 19 in/hg at idle and 23 or so with throttle. I didn't have any other diagnostic tools, so I put my toy on the trailer and went home.
I guess I have to reinstall my intake manifold again - this time I am going to uses those cork strips on the front and back.
A plug blowing out seems like it would be from a lean mixture. I could check the flow from the fuel pump, but this is my third fuel pump. Everything else on the fuel line is 3/8 and I even eliminated all the L's, so the fuel flow is smooth. The new fuel filter is at least four times the size of my old one. There is also a 3/8" anti-siphon valve and a new vent. I have been all though the fuel supply, including cleaning the tank. The gas is fairly recent. and has marine Stabil in it.
The iridium plugs are pre-gapped to .051 instead of the standard .030, so could change back to the standard plugs and maybe tone things down a bit.
My Chinese knock-off of an Edelbrock 1409 4-barrel carb says it only needs 5-6 psi, and I believe I have that from my fuel pump, but I will check. The Holley was not any better and was worse at idle. I couldn't tell if the secondaries of the 4-barrel carb came on or not.
I am not sure what I have to do to get more fuel to the cylinders, if that is my problem. I would change it to fuel injection, if that were feasible, but that is just my "hot rod" mentality. I probably don't want to bump up the horsepower any more than it is. Or I could be satisfied with staying under 3000 rpm, but that is not likely. I am more likely to put a supercharger on it, but I will restrain myself.
Any ideas?
