Stephan427sc
05-31-2025, 02:53 AM
Hi, I use a MSD ditributor with a vacuum port an my ford 302 engine. To which port of the carb needs the vacuum of the distributor connected ? Spark or full manifold vac ? Thanks, Stephan
weendoggy
05-31-2025, 07:18 AM
Manifold vacuum. Plug it to set base timing, then plug it back in.
i.e.427
06-01-2025, 04:28 PM
For most street engines, ported vacuum is the recommended choice. Holley and MSD recommend it.
If you have a high-performance engine with a large camshaft, ported vacuum is still a good choice. It can help to improve throttle response and prevent pinging.
If you are running a high-compression engine, full vacuum may be more appropriate. It provides more timing advance at low speeds, which can help to improve idle quality and reduce the risk of pinging
Frank