First I just wanted to say hi to everybody here I haven't posted before but I have gotten some good info.
I have an 18' 86 Mach 1
5.0L 305
OMC Cobra
Here is my problem. I was having 3 main issues with my original Q-Jet carb. First one was it had the old stove pipe choke that bolted to the manifold well it wasn't working anymore. Second the carb would leak down overnight and Third when I would go from idle to full throttle the engine would hesitate and I would have to back off the throttle and slowly put it on. Making it a PIA to pull a skier out of the water. With all that said I never was a huge fan of Q-Jets anyway so I decided to replace it with an Edelbrock carb. I installed a 1406 600 cfm. I know its not the marine application but I am not running in the ocean only in a small lake and not concerned with the fire hazard. I know I will probably take some crap for saying that but it is what it is.
Anyway here is my problem now. After installing the new carb now I am only getting 4,000 rpms at WOT. Before changing carbs I was getting 5K. I have gone through the entire ignition system. I have replaced cap, rotor, plugs, wires, points, and coil. I have checked timing to make sure that it is spot on. I have checked fuel pressure and am getting a solid 5psi which is what Edelbrock recommends. I am in Denver so I do have altitude to deal with. I have been playing with jets and have had to go two stages lean on the primary side to compensate for the altitude and have it running great except for the WOT and only getting 4K. I have tried several different secondary jet combos with no change in the WOT rpms. I even hooked up a second tach to verify that the tach was correct. I forgot to mention this is only when there is a load on the muffs it will rev way past the 5k although I have only done it for a split second at a time.
Is there anybody out there that has installed a 1406 or has has similar problems. Everything else on the boat it the same. Haven't touched the prop etc.
I have an 18' 86 Mach 1
5.0L 305
OMC Cobra
Here is my problem. I was having 3 main issues with my original Q-Jet carb. First one was it had the old stove pipe choke that bolted to the manifold well it wasn't working anymore. Second the carb would leak down overnight and Third when I would go from idle to full throttle the engine would hesitate and I would have to back off the throttle and slowly put it on. Making it a PIA to pull a skier out of the water. With all that said I never was a huge fan of Q-Jets anyway so I decided to replace it with an Edelbrock carb. I installed a 1406 600 cfm. I know its not the marine application but I am not running in the ocean only in a small lake and not concerned with the fire hazard. I know I will probably take some crap for saying that but it is what it is.
Anyway here is my problem now. After installing the new carb now I am only getting 4,000 rpms at WOT. Before changing carbs I was getting 5K. I have gone through the entire ignition system. I have replaced cap, rotor, plugs, wires, points, and coil. I have checked timing to make sure that it is spot on. I have checked fuel pressure and am getting a solid 5psi which is what Edelbrock recommends. I am in Denver so I do have altitude to deal with. I have been playing with jets and have had to go two stages lean on the primary side to compensate for the altitude and have it running great except for the WOT and only getting 4K. I have tried several different secondary jet combos with no change in the WOT rpms. I even hooked up a second tach to verify that the tach was correct. I forgot to mention this is only when there is a load on the muffs it will rev way past the 5k although I have only done it for a split second at a time.
Is there anybody out there that has installed a 1406 or has has similar problems. Everything else on the boat it the same. Haven't touched the prop etc.
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