350 motor has no power

I put in a fresh rebuilt 68' 350 chevy motor with 410 hp. I got it all hooked up, and i have a problem when i try to accelarate, it feels similar to the power of my old original 283 motor. It literally feels like im getting maybe 150ish hp. When i push the pedal down, the car's power curve will increase slowly, even when i jam the pedal down further, the car just slowly steadily increases in speed at a slow rate.( 0 - 60mph in about 11 seconds). When i hit WOT, the secondaries kick in, and i get nothing except a very slight chug, as if it went lean for a split second. Im using an edelbrock 800 cfm thunder series carb. an edelbrock performance fuel pump (preset at 6psi), hooker headers, i have an HEI distributor with bosh platinum plugs gapped at .45, and 8mm wires. Ive only done the inital timing and it is set at 10 degrees BTDC (with the vacuum canister plugged). I havent determined my total timing yet, but the car seems to advanced quickly when i pulled the carb throttle linkage back, while holding a timining light on the timing mark I have a 2500 stall, and a cam with a 485 lift and around 287/287 duration. So the car likes to idle high, about 900 -

1100 rpms... But basically.... The motor sounds strong at idle, and sounds strong when im driving it. Just no power and poor accelaration. I should be feeling at least 200 more horses. this is my first motor swap, so im a newb. any ideas? thanks for any help or info you can give. ~Scotty
Reply to
Scotty
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Is the distributer got a vacuum advance? I once got my vacuum lines backwards and had similar symptoms.

Reply to
Mike Copeland

thanks for the idea mike, ill try straight running it without a vacuum advance an see if it helps, then maybe i can get an idea if thats the problem. Alot of people think its being over Carbed, so ill toss a smaller carb on it

Reply to
Scotty

What jetting are you running in the carb?

Does the idle change when you unhook the vacuum advance line?

Is the vacuum advance working?

Is the mechanical advance working?

What are you running for headers, mufflers, exhaust?

What intake?

Is the HEI all stock?

What heads?

What compression?

What octane gas?

I recommend ditching the Bosch Platinum's in favor of some Accel U-grooves. I have dealt allot with power losses in carbed engines when Bosch Platinum's were installed.

Reply to
Shades

I read this whole thread and I don't understand why you are posting this without giving us the whole story. What is your "car"? Is it a truck? What is the rear-end ratio? What size tires? Who said it is a

410 HP 350 ( would require high compression and high RPM). How heavy is your "car"? Have you observed the spark advance as the revs increase. Please fill in the blanks!
Reply to
brianorion

Reply to
Andrew

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