I have a 69 Cutlass S convertible. Original 350 V8 with the original Turbo 350 tranny. Is there a particular vacuum nipple that I need to connect the modulator pipe to? I had a Holley 4BBL 650 installed on the motor with an Edelbrock intake. There's a small vacuum nipple at the very bottom of the Holley at the front of the carb. It's not the large vacuum nipple on the back. I assume that ones for the brakes.



front of carb

 

Any full manifold vacuum source (not the timed/ported source) will work.

 

The port on this runner is where the factory connected the vacuum modulator. On my car, I just swapped the nipple from the original iron manifold to the RPM manifold. Made connection easy and I didn't have to bend the modulator hard line.