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I've got a question for the engine gurus who frequent this site. My dad is building a 38 Ford pickup street rod - he's got a decently built little 302 as the power plant - the block is a 1979 Mustang block. The block was machined and bored slightly. All internals are new, and the heads were rebuilt, have new valves, lifters, etc. The cam is pretty mild (not one that should lope at idle). The compression ratio is not super high, I want to say 9:1 or so. It's got a brand new Edelbrock Performer aluminum intake and has had a variety of carbs mounted as testers.
Here's the problem: the thing will not run well when its turning less than 1000 RPMs. It sounds very healthy once the revs are up (as any small block with headers and flowmasters does) and runs very smooth at higher rpms.
Proper cam break-in procedures were followed. It has run the same way with numerous carburetors (a couple of Edelbrocks and a couple of others) and even after swapping a different set of heads on, it still acts like this. There are no vacuum leaks that he's aware of, the timing has been checked and re-checked. He's even swapped distributors and also tried the later model firing order to make sure that the wrong cam wasn't installed.
This is really getting frustrating. I am out of ideas to suggest and he's picked the brains of several mechanic friends of his. He is now borrowing a friend's two-barrel cast iron intake and a 2-bbl carb to try and rule out a problem with the intake manifold.
Does anybody have any other suggestions? I know its a stretch but I figured I'd give this board a shot... Maybe somebody else has seen something similar?
Here's the problem: the thing will not run well when its turning less than 1000 RPMs. It sounds very healthy once the revs are up (as any small block with headers and flowmasters does) and runs very smooth at higher rpms.
Proper cam break-in procedures were followed. It has run the same way with numerous carburetors (a couple of Edelbrocks and a couple of others) and even after swapping a different set of heads on, it still acts like this. There are no vacuum leaks that he's aware of, the timing has been checked and re-checked. He's even swapped distributors and also tried the later model firing order to make sure that the wrong cam wasn't installed.
This is really getting frustrating. I am out of ideas to suggest and he's picked the brains of several mechanic friends of his. He is now borrowing a friend's two-barrel cast iron intake and a 2-bbl carb to try and rule out a problem with the intake manifold.
Does anybody have any other suggestions? I know its a stretch but I figured I'd give this board a shot... Maybe somebody else has seen something similar?
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