Any idea why SU carbs would have resistance right as it opens? It's fine once you're driving but starting from a stop there's pressure on the pedal and throttle valve to a point where it is very difficult to accelerate smoothly from a stop. It requires more pressure on the throttle than it should to get the engine to open up, but only from idle. So it causes the rpm to jump up to almost 2.5k when im trying to accelerate smooth. And it only happens when the car is running. There isn't any throttle resistance when the car is off. Its not the pedal itself sticking or the throttle cable.

vg30drift wrote:Any idea why SU carbs would have resistance right as it opens? It's fine once you're driving but starting from a stop there's pressure on the pedal and throttle valve to a point where it is very difficult to accelerate smoothly from a stop. It requires more pressure on the throttle than it should to get the engine to open up, but only from idle. So it causes the rpm to jump up to almost 2.5k when im trying to accelerate smooth. And it only happens when the car is running. There isn't any throttle resistance when the car is off. Its not the pedal itself sticking or the throttle cable.

Check the bell crank arm on the firewall, it's probably over center. If it's in a 510 , you'll need to rotate the "hook" pivot, counter clockwise.

^ I think Doc is right - Sounds like the bell crank arm is "locking" at the beginning of its motion (kind of like a knee bending backwards - OUCH!)