83 Mazda Rx7

[Spikep]

It sounds like you have a lean condition. Check fuel flow from the electric pump, you may have to jumper the fuel relay, it's under the dash on the right side of the steering column. Check the vacuum hoses for leaks or open ports on the carb. The Nikki carbs are not that hard to work on, NAPA can get the carb kit, and it's not that difficult to clean up and re-gasket. Helps if you have a shop manual but the instructions with the kit are good.
Check the spark plugs, they foul easy, especially if you have flooded it, also make sure you have the plug wires on the correct plug.
I hope this helps.

Spike

[lateapex911]

Check the fuel filter, of course. The old tanks are rust buckets by now, so it's coomon to clog a fuel filter with rust. And if there's no filter, well, a carb teardown/cleaning might be in order. I run a filter right at the entry to the carb, and I use the clear type. Easier to check. There is one stock on the car under the drivers butt, or a bit further back. It's easily ignored.

As mentioned, check the vacuum hoses. They are old, and prone to cracking, stiffening, etc. There are some oddities like the "flapper valve" that can malfunction, but this doens't sound like that's happening.

[tom_sprecher]

Like some have said, rebuilding the carb is not hard, especially if it has been prepped for racing.