Hi everyone. I have a Chevy van/sleeper project that is driving me absolutely nuts. I have hit that issue that I hope someone had solved.
I have an 86 Chevy van G20, conversion. I have gutted the interior, modified the suspension, front and rear. I had a stock engine that I modified with a .196/.204 cam, It has been bored .030 over, planed, the heads were replaced with 64cc., emissions heads. I have an Edelbrock performer manifold, intake and exhaust port matched with an Edelbrock 1400 EGR carb. All the emissions have been restored on the vehicle.
At about 8000 miles, the engine started missing. I changed the plugs, wires, module. I replaced the distributor. I have the engine timed at factory 4bdc. I have retuned the carburator. The plugs came out on the right facing forward, back, black, three back, white, two back white, one, black.
It has pronounced hesitation from a start and I had to set the idle to 750 to miss the hesitation. Oil pressure is 68lbs on start up, with 48lbs at normal running temperature, 28lbs at idle at 750, 22lbs at 550.
On the Edlebrock I am 1 1/2 turns out from closed and tweaking 1/8th turn at a time.
It has dual pipes with crossover. It sounds smooth from the outside, and powerful. Inside you can feel a shudder, and it feels like it has less power. Fuel mileage is about 18 around town. I do not know highway.
Hoses are new and tight, no vaccum leaks. I am lost. Can anybody help?